1381 lines
285 KiB
XML
1381 lines
285 KiB
XML
<document ID-DOI="10.1038/s42003-022-03144-y" ID-GBIF-Dataset="d1a6a909-07ed-4903-a5bc-ecd1b05f3865" ID-PMC="PMC8894340" ID-PubMed="35241764" ID-Zenodo-Dep="6346784" approvalRequired="1" approvalRequired_for_document="1" checkinTime="1647002513460" checkinUser="diego" docAuthor="Simões, Tiago R., Kinney-Broderick, Grace & Pierce, Stephanie E." docDate="2022" docId="038487ECFFF0FFC8860B9AA0D1A1C310" docLanguage="en" docName="communBiol.5.195.1-19.pdf" docOrigin="Communications Biology 5 (1)" docSource="http://dx.doi.org/10.1038/s42003-022-03144-y" docTitle="Navajosphenodon sani Simões & Kinney-Broderick & Pierce 2022, gen. et sp. nov." docType="treatment" docVersion="5" lastPageNumber="13" masterDocId="FFBDFF94FFF1FFC585209F15D01FC77C" masterDocTitle="An exceptionally preserved Sphenodon-like sphenodontian reveals deep time conservation of the tuatara skeleton and ontogeny" masterLastPageNumber="19" masterPageNumber="1" pageNumber="2" updateTime="1668126831655" updateUser="ExternalLinkService" zenodo-license-document="CC-BY-4.0">
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<mods:mods xmlns:mods="http://www.loc.gov/mods/v3">
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<mods:titleInfo>
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||
<mods:title>An exceptionally preserved Sphenodon-like sphenodontian reveals deep time conservation of the tuatara skeleton and ontogeny</mods:title>
|
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</mods:titleInfo>
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<mods:name type="personal">
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<mods:role>
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<mods:roleTerm>Author</mods:roleTerm>
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</mods:role>
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<mods:namePart>Simões, Tiago R.</mods:namePart>
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</mods:name>
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<mods:name type="personal">
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<mods:role>
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<mods:roleTerm>Author</mods:roleTerm>
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</mods:role>
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<mods:namePart>Kinney-Broderick, Grace</mods:namePart>
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</mods:name>
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<mods:name type="personal">
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<mods:role>
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<mods:roleTerm>Author</mods:roleTerm>
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</mods:role>
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<mods:namePart>Pierce, Stephanie E.</mods:namePart>
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</mods:name>
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<mods:typeOfResource>text</mods:typeOfResource>
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<mods:relatedItem type="host">
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<mods:titleInfo>
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<mods:title>Communications Biology</mods:title>
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</mods:titleInfo>
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<mods:part>
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<mods:date>2022</mods:date>
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<mods:detail type="pubDate">
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<mods:number>2022-03-03</mods:number>
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</mods:detail>
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<mods:detail type="volume">
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||
<mods:number>5</mods:number>
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</mods:detail>
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<mods:detail type="issue">
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<mods:number>1</mods:number>
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</mods:detail>
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<mods:extent unit="page">
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<mods:start>1</mods:start>
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<mods:end>19</mods:end>
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</mods:extent>
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</mods:part>
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</mods:relatedItem>
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<mods:location>
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<mods:url>http://dx.doi.org/10.1038/s42003-022-03144-y</mods:url>
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</mods:location>
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<mods:classification>journal article</mods:classification>
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<mods:identifier type="DOI">10.1038/s42003-022-03144-y</mods:identifier>
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<mods:identifier type="GBIF-Dataset">d1a6a909-07ed-4903-a5bc-ecd1b05f3865</mods:identifier>
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<mods:identifier type="PMC">PMC8894340</mods:identifier>
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<mods:identifier type="PubMed">35241764</mods:identifier>
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<mods:identifier type="Zenodo-Dep">6346784</mods:identifier>
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<treatment ID-DOI="http://doi.org/10.5281/zenodo.6346749" ID-GBIF-Taxon="193939796" ID-Zenodo-Dep="6346749" LSID="urn:lsid:plazi:treatment:038487ECFFF0FFC8860B9AA0D1A1C310" httpUri="http://treatment.plazi.org/id/038487ECFFF0FFC8860B9AA0D1A1C310" lastPageId="13" lastPageNumber="13" pageId="1" pageNumber="2">
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<subSubSection box="[811,1204,1461,1483]" pageId="1" pageNumber="2" type="nomenclature">
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<paragraph blockId="1.[810,1394,1321,1483]" box="[811,1204,1461,1483]" pageId="1" pageNumber="2">
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<heading box="[811,1204,1461,1483]" level="2" pageId="1" pageNumber="2">
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<taxonomicName authority="Simões & Kinney-Broderick & Pierce, 2022" authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[811,1038,1461,1483]" family="Sphenodontidae" genus="Navajosphenodon" kingdom="Animalia" order="Sphenodontia" pageId="1" pageNumber="2" rank="species" species="sani" status="gen. et sp. nov.">
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<emphasis box="[811,1038,1461,1483]" italics="true" pageId="1" pageNumber="2">Navajosphenodon sani</emphasis>
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</taxonomicName>
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<taxonomicNameLabel box="[1047,1204,1462,1483]" pageId="1" pageNumber="2" rank="species">gen. et sp. nov.</taxonomicNameLabel>
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</heading>
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</paragraph>
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</subSubSection>
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<subSubSection pageId="1" pageNumber="2" type="etymology">
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<paragraph blockId="1.[810,1472,1531,1693]" pageId="1" pageNumber="2">
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<emphasis bold="true" box="[810,922,1531,1552]" pageId="1" pageNumber="2">Etymology</emphasis>
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. Genus epithet comes from a combination of “Navajo,” in honor of the native people from North America that inhabit the
|
||
<collectingRegion box="[933,1027,1587,1609]" country="United States of America" name="Colorado" pageId="1" pageNumber="2">Colorado</collectingRegion>
|
||
Plateau where the specimens were found, and “sphenodon,” in reference to the modern tuatara
|
||
<taxonomicName class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="1" pageNumber="2" phylum="Chordata" rank="species" species="punctatus">
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||
<emphasis italics="true" pageId="1" pageNumber="2">Sphenodon punctatus</emphasis>
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||
</taxonomicName>
|
||
. Species epithet “sani,” meaning “old age” in the Navajo language.
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||
</paragraph>
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||
</subSubSection>
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<caption ID-DOI="http://doi.org/10.5281/zenodo.6346786" ID-Zenodo-Dep="6346786" httpUri="https://zenodo.org/record/6346786/files/figure.png" pageId="1" pageNumber="2" startId="1.[116,146,1728,1747]" targetBox="[127,767,700,1704]" targetPageId="1">
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<paragraph blockId="1.[116,780,1727,1970]" pageId="1" pageNumber="2">
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||
<emphasis bold="true" box="[116,655,1727,1747]" pageId="1" pageNumber="2">
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||
Fig. 1 Holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[282,480,1727,1747]" genus="Navajosphenodon" pageId="1" pageNumber="2" rank="species" species="sani">
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||
<emphasis bold="true" box="[282,480,1727,1747]" italics="true" pageId="1" pageNumber="2">Navajosphenodon sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442). a
|
||
</emphasis>
|
||
As preserved in the sedimentary matrix in ventral view.
|
||
<emphasis bold="true" box="[496,507,1756,1775]" pageId="1" pageNumber="2">b</emphasis>
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||
Micro CT-scanned and segmented whole skeleton in ventral view;
|
||
<emphasis bold="true" box="[503,513,1783,1802]" pageId="1" pageNumber="2">c</emphasis>
|
||
Micro CT-scanned and segmented whole skeleton in dorsal view (embedded within the sedimentary matrix). Ca.V. caudal vertebrae, Ce.V. cervical vertebrae, Do.V. dorsal vertebrae, Do.R. dorsal ribs, Fe femur, Fi fibula, H humerus, Ma manus, Pe.G. pectoral girdle, Pel.G. pelvic girdle, Ra radius, Ti tibia, Ul ulna. (l) left side and (r) right side. Note: this specimen was previously cataloged as MCZ VP 9016. Scale bar = 10 mm.
|
||
</paragraph>
|
||
</caption>
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<subSubSection lastPageId="2" lastPageNumber="3" pageId="1" pageNumber="2" type="materials_examined">
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<paragraph blockId="1.[810,1471,1740,1818]" pageId="1" pageNumber="2">
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<materialsCitation ID-GBIF-Occurrence="3699956309" collectionCode="MNA" country="United States of America" county="Coconino County" location="Kayenta Formation" pageId="1" pageNumber="2" specimenCode="MNA.V.12442" specimenCount="1" stateProvince="Arizona" typeStatus="holotype">
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<emphasis bold="true" box="[810,907,1741,1762]" pageId="1" pageNumber="2">
|
||
<typeStatus box="[810,907,1741,1762]" pageId="1" pageNumber="2">Holotype</typeStatus>
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</emphasis>
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||
.
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<specimenCode box="[929,1077,1741,1762]" pageId="1" pageNumber="2">
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<collectionCode box="[929,990,1741,1762]" country="Italy" httpUri="http://grbio.org/cool/e1gk-b74h" name="The Museo Nazionale dell'Antartide (Italian National Antarctic Museum in Genoa)." pageId="1" pageNumber="2">MNA</collectionCode>
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.
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<collectionCode box="[993,1011,1741,1762]" country="Canada" lsid="urn:lsid:biocol.org:col:13946" name="Royal British Columbia Museum - Herbarium" pageId="1" pageNumber="2" type="Museum">V</collectionCode>
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.12442
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</specimenCode>
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(previously cataloged as
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<collectionCode box="[1369,1423,1741,1762]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[1439,1471,1741,1762]" pageId="1" pageNumber="2">VP</collectionCode>
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9016), a fully articulated skeleton, including the skull, mandibles, axial and appendicular skeleton (
|
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<figureCitation box="[1149,1208,1796,1818]" captionStart="Fig" captionStartId="1.[116,146,1728,1747]" captionTargetBox="[127,767,700,1704]" captionTargetId="figure-719@1.[127,767,700,1704]" captionTargetPageId="1" captionText="Fig. 1 Holotype of Navajosphenodon sani (MNA.V.12442). a As preserved in the sedimentary matrix in ventral view. b Micro CT-scanned and segmented whole skeleton in ventral view; c Micro CT-scanned and segmented whole skeleton in dorsal view (embedded within the sedimentary matrix). Ca.V. caudal vertebrae, Ce.V. cervical vertebrae, Do.V. dorsal vertebrae, Do.R. dorsal ribs, Fe femur, Fi fibula, H humerus, Ma manus, Pe.G. pectoral girdle, Pel.G. pelvic girdle, Ra radius, Ti tibia, Ul ulna. (l) left side and (r) right side. Note: this specimen was previously cataloged as MCZ VP 9016. Scale bar = 10 mm." figureDoi="http://doi.org/10.5281/zenodo.6346786" httpUri="https://zenodo.org/record/6346786/files/figure.png" pageId="1" pageNumber="2">Fig. 1</figureCitation>
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).
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</materialsCitation>
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</paragraph>
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<paragraph blockId="1.[810,1471,1866,1972]" pageId="1" pageNumber="2">
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<emphasis bold="true" box="[810,1006,1866,1888]" pageId="1" pageNumber="2">Referred materials</emphasis>
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.
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<materialsCitation ID-GBIF-Occurrence="3699956307" box="[1020,1178,1866,1887]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 9098" specimenCount="1">
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<specimenCode box="[1020,1174,1866,1887]" pageId="1" pageNumber="2">
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<collectionCode box="[1020,1074,1866,1887]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[1083,1115,1866,1887]" pageId="1" pageNumber="2">VP</collectionCode>
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9098
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||
</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956308" box="[1186,1368,1866,1888]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 101562" specimenCount="1">
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<specimenCode box="[1186,1364,1866,1888]" pageId="1" pageNumber="2">
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<collectionCode box="[1186,1240,1866,1887]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<accessionNumber box="[1249,1364,1866,1888]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101562" pageId="1" pageNumber="2">
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<collectionCode box="[1249,1281,1866,1887]" pageId="1" pageNumber="2">VP</collectionCode>
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101562
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</accessionNumber>
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</specimenCode>
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,
|
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956305" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 9099" specimenCount="1">
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<specimenCode pageId="1" pageNumber="2">
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<collectionCode box="[1377,1431,1866,1887]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[1439,1471,1866,1887]" pageId="1" pageNumber="2">VP</collectionCode>
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9099
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</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956311" box="[872,1054,1894,1916]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 101564" specimenCount="1">
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<specimenCode box="[872,1049,1894,1916]" pageId="1" pageNumber="2">
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<collectionCode box="[872,926,1894,1915]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<accessionNumber box="[935,1049,1894,1916]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101564" pageId="1" pageNumber="2">
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<collectionCode box="[935,967,1894,1915]" pageId="1" pageNumber="2">VP</collectionCode>
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101564
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</accessionNumber>
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</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956310" box="[1062,1243,1894,1916]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 101575" specimenCount="1">
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<specimenCode box="[1062,1239,1894,1916]" pageId="1" pageNumber="2">
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<collectionCode box="[1062,1116,1894,1915]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<accessionNumber box="[1124,1239,1894,1916]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101575" pageId="1" pageNumber="2">
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<collectionCode box="[1124,1156,1894,1915]" pageId="1" pageNumber="2">VP</collectionCode>
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101575
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</accessionNumber>
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</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956301" box="[1252,1409,1894,1915]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 9094" specimenCount="1">
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<specimenCode box="[1252,1405,1894,1915]" pageId="1" pageNumber="2">
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<collectionCode box="[1252,1306,1894,1915]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[1314,1346,1894,1915]" pageId="1" pageNumber="2">VP</collectionCode>
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9094
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</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956302" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 9102" specimenCount="1">
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<specimenCode pageId="1" pageNumber="2">
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<collectionCode box="[1417,1471,1894,1915]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[810,842,1922,1943]" pageId="1" pageNumber="2">VP</collectionCode>
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9102
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</specimenCode>
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,
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</materialsCitation>
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<materialsCitation ID-GBIF-Occurrence="3699956306" box="[917,1079,1922,1943]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 9103" specimenCount="1">
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<specimenCode box="[917,1075,1922,1943]" pageId="1" pageNumber="2">
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<collectionCode box="[917,971,1922,1943]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
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<collectionCode box="[982,1014,1922,1943]" pageId="1" pageNumber="2">VP</collectionCode>
|
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9103
|
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</specimenCode>
|
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,
|
||
</materialsCitation>
|
||
<materialsCitation ID-GBIF-Occurrence="3699956312" box="[1089,1275,1922,1944]" collectionCode="MCZ" pageId="1" pageNumber="2" specimenCode="MCZ VP 101569" specimenCount="1">
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<specimenCode box="[1089,1271,1922,1944]" pageId="1" pageNumber="2">
|
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<collectionCode box="[1089,1143,1922,1943]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
|
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<accessionNumber box="[1154,1271,1922,1944]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101569" pageId="1" pageNumber="2">
|
||
<collectionCode box="[1154,1186,1922,1943]" pageId="1" pageNumber="2">VP</collectionCode>
|
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101569
|
||
</accessionNumber>
|
||
</specimenCode>
|
||
,
|
||
</materialsCitation>
|
||
<materialsCitation ID-GBIF-Occurrence="3699956303" collectionCode="MCZ, MNA" pageId="1" pageNumber="2" specimenCode="MCZ VP 101563, MNA.V.8726(A-F)" specimenCount="1">
|
||
<specimenCode box="[1286,1467,1922,1944]" pageId="1" pageNumber="2">
|
||
<collectionCode box="[1286,1340,1922,1943]" country="USA" httpUri="http://biocol.org/urn:lsid:biocol.org:col:33791" lsid="urn:lsid:biocol.org:col:33791" name="Museum of Comparative Zoology" pageId="1" pageNumber="2" type="Museum">MCZ</collectionCode>
|
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<accessionNumber box="[1350,1467,1922,1944]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101563" pageId="1" pageNumber="2">
|
||
<collectionCode box="[1350,1382,1922,1943]" pageId="1" pageNumber="2">VP</collectionCode>
|
||
101563
|
||
</accessionNumber>
|
||
</specimenCode>
|
||
,
|
||
<specimenCode box="[810,1003,1950,1972]" pageId="1" pageNumber="2">
|
||
<collectionCode box="[810,872,1950,1972]" country="Italy" httpUri="http://grbio.org/cool/e1gk-b74h" name="The Museo Nazionale dell'Antartide (Italian National Antarctic Museum in Genoa)." pageId="1" pageNumber="2">MNA</collectionCode>
|
||
.
|
||
<collectionCode box="[874,892,1950,1972]" country="Canada" lsid="urn:lsid:biocol.org:col:13946" name="Royal British Columbia Museum - Herbarium" pageId="1" pageNumber="2" type="Museum">V</collectionCode>
|
||
.8726(A-F)
|
||
</specimenCode>
|
||
,
|
||
</materialsCitation>
|
||
<materialsCitation ID-GBIF-Occurrence="3699956304" box="[1016,1157,1950,1971]" collectionCode="MNA" pageId="1" pageNumber="2" specimenCode="MNA.V.8727" specimenCount="1">
|
||
<specimenCode box="[1016,1153,1950,1971]" pageId="1" pageNumber="2">
|
||
<collectionCode box="[1016,1078,1950,1971]" country="Italy" httpUri="http://grbio.org/cool/e1gk-b74h" name="The Museo Nazionale dell'Antartide (Italian National Antarctic Museum in Genoa)." pageId="1" pageNumber="2">MNA</collectionCode>
|
||
.
|
||
<collectionCode box="[1081,1099,1950,1971]" country="Canada" lsid="urn:lsid:biocol.org:col:13946" name="Royal British Columbia Museum - Herbarium" pageId="1" pageNumber="2" type="Museum">V</collectionCode>
|
||
.8727
|
||
</specimenCode>
|
||
.
|
||
</materialsCitation>
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="1" pageNumber="2">
|
||
<paragraph blockId="1.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="1" pageNumber="2">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<paragraph blockId="2.[116,778,135,242]" pageId="2" pageNumber="3">
|
||
<emphasis bold="true" box="[116,342,136,158]" pageId="2" pageNumber="3">Locality and horizon</emphasis>
|
||
. “Silty facies” of the
|
||
<location LSID="urn:lsid:plazi:treatment:038487ECFFF0FFC8860B9AA0D1A1C310:8EF26021FFF3FFC7871C9F9CD319C7E2" box="[572,774,136,158]" country="United States of America" county="Coconino County" name="Kayenta Formation" pageId="2" pageNumber="3" stateProvince="Arizona">Kayenta Formation</location>
|
||
,
|
||
<location LSID="urn:lsid:plazi:treatment:038487ECFFF0FFC8860B9AA0D1A1C310:8EF26021FFF3FFC785549FB1D220C7C5" box="[116,575,163,186]" country="United States of America" county="Coconino County" name="Glen Canyon Group - Gold Springs Quarry" pageId="2" pageNumber="3" stateProvince="Arizona">Glen Canyon Group—Gold Springs Quarry</location>
|
||
and Main Quarry,
|
||
<location LSID="urn:lsid:plazi:treatment:038487ECFFF0FFC8860B9AA0D1A1C310:8EF26021FFF3FFC785549FD5D134C7AA" box="[116,299,192,214]" country="United States of America" county="Coconino County" name="Adeii Eechii Cliffs" pageId="2" pageNumber="3" stateProvince="Arizona">Adeii Eechii Cliffs</location>
|
||
,
|
||
<collectingCounty box="[309,491,192,214]" pageId="2" pageNumber="3">Coconino County</collectingCounty>
|
||
,
|
||
<collectingRegion box="[501,584,192,214]" country="United States of America" name="Arizona" pageId="2" pageNumber="3">Arizona</collectingRegion>
|
||
,
|
||
<collectingCountry box="[593,643,192,213]" name="United States of America" pageId="2" pageNumber="3">USA</collectingCountry>
|
||
.
|
||
<geologicalTimeScale pageId="2" pageNumber="3">Sinemurian-Pliensbachian, Early Jurassic26</geologicalTimeScale>
|
||
.
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection pageId="2" pageNumber="3" type="diagnosis">
|
||
<paragraph blockId="2.[116,778,304,856]" pageId="2" pageNumber="3">
|
||
<emphasis bold="true" box="[116,220,304,326]" pageId="2" pageNumber="3">Diagnosis</emphasis>
|
||
. Can be distinguished from all other species of sphenodontians by the following combination of features: premaxillae with no posterior maxillary process*; premaxillae with welldeveloped posterodorsal process; jugal with a wide posterodorsal process and a well-developed posteroventral process (contributing to a complete lower temporal bar); absence of a dorsolateral concavity on the surface of the postorbital; squamosal dorsal process bifurcated distally*; quadrate-quadratojugal completely fused; straight posterior margin of the quadrate-quadratojugal complex; presence of pterygoid teeth; presence of arcuate flanges on the pterygoids; dentary symphysial region small and slightly curved medially, premaxillary teeth present as discrete elements; quadrangular tooth bases for the additional tooth series; presence of caniniform successional teeth on the anterior end of the dentary; presence of posteromedially directed flanges on maxillary alternating teeth; presence of a midventral crest throughout the entire vertebral series; penultimate phalanges longer than preceding phalanges*; ungual phalanges tall at their bases. (*) Indicates features exclusively known in
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[513,583,807,828]" genus="Navajosphenodon" pageId="2" pageNumber="3" rank="species" species="sani">
|
||
<emphasis box="[513,583,807,828]" italics="true" pageId="2" pageNumber="3">N. sani</emphasis>
|
||
</taxonomicName>
|
||
relative to all other sphenodontians.
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection lastPageId="10" lastPageNumber="11" pageId="2" pageNumber="3" type="description">
|
||
<paragraph blockId="2.[116,779,917,1972]" pageId="2" pageNumber="3">
|
||
<emphasis bold="true" box="[116,670,917,940]" pageId="2" pageNumber="3">Morphological description and comparisons—skull</emphasis>
|
||
. The premaxillae are paired (
|
||
<figureCitation box="[314,370,945,967]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Fig. 2</figureCitation>
|
||
), with the left premaxilla better preserved than its right counterpart and in articulation with the left maxilla (
|
||
<figureCitation box="[123,182,1001,1023]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">Fig. 3</figureCitation>
|
||
). The nasal process is slightly curved and directed posterodorsally (
|
||
<figureCitation box="[223,294,1029,1051]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">Fig. 3a</figureCitation>
|
||
), indicating the anterior end of the snout was smoothly curved and was not dorsoventrally deep as in clevosaurids3,27,28. The posterodorsal process of the premaxilla is extremely elongate, reaching posteriorly as far as the apex of the nasal (=facial) process of the maxilla and forming most of the posterior margin of the external nares. In contrast to most sphenodontians and other diapsid reptiles, the premaxillae do not possess a maxillary process distinct from the posterodorsal process extending posteriorly to contact the maxilla (
|
||
<figureCitation box="[578,637,1252,1274]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Fig. 2</figureCitation>
|
||
). Instead, the maxilla reaches anteriorly to contact the main body of the premaxilla at the level of the distalmost premaxillary tooth. The left premaxilla has three acrodont teeth preserved in situ and not forming the ventrally expanded dentigerous beak observed in most sphenodontians—a condition more commonly observed in early sphenodontians, such as
|
||
<taxonomicName authorityName="Evans" authorityYear="1980" box="[368,513,1420,1441]" class="Reptilia" family="Gephyrosauridae" genus="Gephyrosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[368,513,1420,1441]" italics="true" pageId="2" pageNumber="3">Gephyrosaurus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Whiteside" authorityYear="1986" box="[568,745,1420,1441]" class="Reptilia" family="Sphenodontidae" genus="Diphydontosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[568,745,1420,1441]" italics="true" pageId="2" pageNumber="3">Diphydontosaurus</emphasis>
|
||
</taxonomicName>
|
||
7,29 (and TRS, pers. obs.).
|
||
</paragraph>
|
||
<paragraph blockId="2.[116,779,917,1972]" pageId="2" pageNumber="3">
|
||
Both maxillae are preserved, with the right element split into two (
|
||
<figureCitation box="[172,243,1503,1525]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[304,331,1503,1525]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3b</figureCitation>
|
||
). The premaxillary process of the maxilla extends well anteriorly to contact the body of the premaxilla. The nasal process is relatively well-developed and descends anteriorly at a smooth angle towards the anterior extremity of the maxilla. Small mental foramina are observed along the edge of the dentigerous margin. At the base of the nasal process, a relatively larger foramen might represent the anterior superior alveolar foramen. The dentigerous portion of the maxilla extends well posteriorly on the skull to the level of the posterior margin of the orbit. The suborbital process of the maxilla thus forms most of the ventral margin of the orbit (more clearly visible on the right maxilla of MNA.V.12442). The
|
||
<typeStatus box="[438,526,1810,1832]" pageId="2" pageNumber="3">holotype</typeStatus>
|
||
has nine teeth preserved on the right maxilla, with space allowing for at least five additional teeth, whereas the left maxilla has eight preserved teeth. Details on dental morphology, replacement, and ontogeny are further discussed below in the sections for “Dentition” and “Ontogeny of jaws and teeth.”
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" pageId="2" pageNumber="3">
|
||
Fragments of the paired nasals are preserved in MNA.V.12442 with the left element lying medially to the nasal process of the left premaxilla, whereas the right nasal bone is preserved medially to the broken apex of the right maxilla (
|
||
<figureCitation box="[1184,1250,220,242]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1301,1328,220,242]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3d</figureCitation>
|
||
). Both are too poorly preserved to recognize how much they contribute to the medial margin of the external nares, but the available data suggests that the nasal process of the premaxilla was the main structure separating the external narial openings. Aventrolateral process of the nasal is present and preserved on the right element.
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" pageId="2" pageNumber="3">
|
||
The prefrontals are dorsoventrally deep and form most of the anterior margin of the orbits (
|
||
<figureCitation box="[1155,1230,415,437]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1298,1322,416,437]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3e</figureCitation>
|
||
), as in most sphenodontians, some stem lepidosauromorphs such as
|
||
<emphasis box="[810,910,471,492]" italics="true" pageId="2" pageNumber="3">Vellbergia</emphasis>
|
||
30, and early-diverging squamate lineages (e.g., geckos). Dorsally, the prefrontal has an extensive articulation with the lateral margin of the frontal, reaching as far back as the midpoint of the orbit. Ventrally, the prefrontal contacts the ascending process of the palatine. There is no evidence of a lacrimal bone nor an articulatory facet on the lateral margin of the prefrontal for a lacrimal articulation and thus we consider the lacrimal to be absent, as in most other sphenodontians. The anteroventral margin of the prefrontal is slightly concave and forms a lateral opening for the exit of the lacrimal duct along with the dorsal margin of the maxilla, as observed in
|
||
<taxonomicName box="[1304,1414,750,771]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1304,1414,750,771]" italics="true" pageId="2" pageNumber="3">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
. The external surface has no visible sculpturing or a prefrontal crest, although the level of sculpturing may have changed in later ontogenetic stages.
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" pageId="2" pageNumber="3">
|
||
One element preserved in between the nasals (dorsally) and the palatal region (ventrally) is interpreted here as the right septomaxilla (
|
||
<figureCitation box="[959,1035,917,939]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1105,1128,917,939]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3f</figureCitation>
|
||
). It is longer than wider and preserves a large facet that would have accommodated the vomeronasal organ.
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" pageId="2" pageNumber="3">
|
||
The left postfrontal is located mostly ventral to the left frontal and separated from the postorbital, indicating it was displaced anteromedially (
|
||
<figureCitation box="[925,979,1057,1079]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Fig. 2</figureCitation>
|
||
). The right postfrontal is located between the right postorbital and the right frontal. The postfrontal is tri-radiated with a relatively broad distal process that articulated with the anterior margin of the postorbital, thus providing a small contribution to the posterodorsal margin of the orbit (
|
||
<figureCitation box="[1149,1214,1169,1191]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1266,1290,1169,1190]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">
|
||
<quantity box="[1266,1290,1169,1190]" metricMagnitude="-3" metricUnit="kg" metricValue="3.0" pageId="2" pageNumber="3" unit="g" value="3.0">3g</quantity>
|
||
</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" pageId="2" pageNumber="3">
|
||
The jugal is a robust element lying medially adjacent to the suborbital process of the maxilla and contributing to the ventral border of the orbit with the latter (
|
||
<figureCitation box="[1210,1283,1252,1274]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1352,1406,1252,1274]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3h, j</figureCitation>
|
||
). The posterodorsal process of the jugal is considerably wide compared to most other diapsids, including other sphenodontians, and it bears along the orbital margin an articulatory facet for articulation with the ventral process of the postorbital (
|
||
<figureCitation box="[1135,1198,1364,1386]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1247,1274,1364,1386]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3k</figureCitation>
|
||
). The posteroventral process is extremely well-developed and the right jugal on MNA.V.12442 suggests this process extends posteriorly to the level of the quadrate-quadratojugal, thus forming a complete (or nearly complete) lower temporal bar (
|
||
<figureCitation box="[1126,1194,1475,1497]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1252,1279,1475,1497]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3h</figureCitation>
|
||
). As the degree of development of the posteroventral process of the jugal is known to be quite variable throughout postembryonic ontogeny both in early sphenodontians7,27 and squamates with a lower temporal bar31— besides considering the subadult stage of the
|
||
<typeStatus box="[1235,1318,1587,1609]" pageId="2" pageNumber="3">holotype</typeStatus>
|
||
(see “Ontogeny of jaw and teeth”)—it is expected that most subadult and adults would have had a complete lower temporal bar, although the condition remains unknown in young juveniles and hatchlings.
|
||
</paragraph>
|
||
<paragraph blockId="2.[810,1472,136,1972]" lastBlockId="3.[116,778,1336,1972]" lastPageId="3" lastPageNumber="4" pageId="2" pageNumber="3">
|
||
The quadrates and quadratojugals form a single fused quadrate-quadratojugal complex with no suture being visible between both elements (
|
||
<figureCitation box="[1061,1130,1754,1776]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="2" pageNumber="3">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1185,1206,1754,1776]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="2" pageNumber="3">3i</figureCitation>
|
||
), as similarly observed in later ontogenetic stages of the modern
|
||
<taxonomicName box="[1250,1359,1782,1803]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1250,1359,1782,1803]" italics="true" pageId="2" pageNumber="3">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
. Aquadratojugal fenestra is seemingly present between the quadrate and quadratojugal and the posterior margin of the quadrate is pillarlike and relatively straight, as observed in
|
||
<taxonomicName box="[1247,1357,1866,1887]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1247,1357,1866,1887]" italics="true" pageId="2" pageNumber="3">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
, instead of forming a posterior emargination as in early evolving sphenodontians—e.g.,
|
||
<taxonomicName authorityName="Evans" authorityYear="1980" box="[967,1116,1922,1943]" class="Reptilia" family="Gephyrosauridae" genus="Gephyrosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[967,1116,1922,1943]" italics="true" pageId="2" pageNumber="3">Gephyrosaurus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Whiteside" authorityYear="1986" box="[1169,1352,1922,1943]" class="Reptilia" family="Sphenodontidae" genus="Diphydontosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="2" pageNumber="3" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1169,1352,1922,1943]" italics="true" pageId="2" pageNumber="3">Diphydontosaurus</emphasis>
|
||
</taxonomicName>
|
||
(TRS, pers. obs. and refs. 7,29). Medially, the quadrate-quadratojugals have a well-developed anteromedially directed and dorsoventrally deep process to contact the pterygoids. Two condyles are distinct on the ventral margin of the quadrate-quadratojugal and are in close proximity to the glenoid facet of the articular bone in the lower jaw.
|
||
</paragraph>
|
||
<footnote box="[431,1126,2007,2023]" pageId="2" pageNumber="3">
|
||
<paragraph blockId="2.[431,1126,2007,2023]" box="[431,1126,2007,2023]" pageId="2" pageNumber="3">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346790" ID-Zenodo-Dep="6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4" startId="3.[116,146,1195,1214]" targetBox="[366,1221,139,1169]" targetPageId="3">
|
||
<paragraph blockId="3.[116,1471,1195,1298]" pageId="3" pageNumber="4">
|
||
<emphasis bold="true" box="[116,1147,1195,1215]" pageId="3" pageNumber="4">
|
||
Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[906,969,1195,1215]" genus="Navajosphenodon" pageId="3" pageNumber="4" rank="species" species="sani">
|
||
<emphasis bold="true" box="[906,969,1195,1215]" italics="true" pageId="3" pageNumber="4">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442). a
|
||
</emphasis>
|
||
Right ventrolateral view.
|
||
<emphasis bold="true" box="[1376,1387,1195,1214]" pageId="3" pageNumber="4">b</emphasis>
|
||
Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="3.[116,778,1336,1972]" pageId="3" pageNumber="4">
|
||
The postorbitals are preserved on both sides of the skull in MNA.V.12442, with the left postorbital nearly completely preserved (apart from a crack dividing its posterior process) and in close contact with the jugal, maxilla, squamosal, and postfrontal (
|
||
<figureCitation box="[243,303,1587,1609]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Fig. 2</figureCitation>
|
||
). The postorbitals are triradiate, with slender dorsal and ventral processes, and a much more dorsoventrally deep and elongate posterior process for the contact with the squamosal (
|
||
<figureCitation box="[235,300,1671,1693]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[349,376,1671,1693]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="3" pageNumber="4">3k</figureCitation>
|
||
). The anteromedial margin of the dorsal and ventral processes of the postorbital preserved the articulatory facets for postfrontal and jugal, respectively.
|
||
</paragraph>
|
||
<paragraph blockId="3.[116,778,1336,1972]" lastBlockId="3.[810,1472,1336,1972]" pageId="3" pageNumber="4">
|
||
The squamosals are preserved on either side of the skull in MNA.V.12442 with the left element in a much better state of preservation (
|
||
<figureCitation box="[256,314,1810,1832]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Fig. 2</figureCitation>
|
||
). The squamosals are tetraradiate as in other sphenodontians and many other early evolving diapsid reptiles— e.g.,
|
||
<taxonomicName authorityName="Broom" authorityYear="1914" box="[161,258,1867,1888]" class="Reptilia" family="Younginidae" genus="Youngina" higherTaxonomySource="GBIF" kingdom="Animalia" order="Younginiformes" pageId="3" pageNumber="4" phylum="Chordata" rank="genus">
|
||
<emphasis box="[161,258,1867,1888]" italics="true" pageId="3" pageNumber="4">Youngina</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Parrington" authorityYear="1935" box="[309,411,1866,1887]" class="Reptilia" family="Protorosauridae" genus="Prolacerta" higherTaxonomySource="GBIF" kingdom="Animalia" order="Protorosauria" pageId="3" pageNumber="4" phylum="Chordata" rank="genus">
|
||
<emphasis box="[309,411,1866,1887]" italics="true" pageId="3" pageNumber="4">Prolacerta</emphasis>
|
||
</taxonomicName>
|
||
(TRS pers. obs.), and differing from the triradiate condition observed in early evolving squamates, such as
|
||
<taxonomicName authorityName="Renesto & Posenato" authorityYear="2003" box="[204,332,1922,1943]" class="Reptilia" family="Scincidae" genus="Megachirella" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="3" pageNumber="4" phylum="Chordata" rank="genus">
|
||
<emphasis box="[204,332,1922,1943]" italics="true" pageId="3" pageNumber="4">Megachirella</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Reynoso" authorityYear="1998" box="[390,562,1922,1943]" class="Reptilia" family="Scincidae" genus="Huehuecuetzpalli" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="3" pageNumber="4" phylum="Chordata" rank="genus">
|
||
<emphasis box="[390,562,1922,1943]" italics="true" pageId="3" pageNumber="4">Huehuecuetzpalli</emphasis>
|
||
</taxonomicName>
|
||
32,33. The squamosal has a strongly developed dorsal process, which would have contacted the supratemporal process of the parietal, and which is bifurcated distally (
|
||
<figureCitation box="[1021,1097,1364,1386]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1166,1186,1364,1386]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="3" pageNumber="4">3l</figureCitation>
|
||
). The anterior process is dorsoventrally deep, elongate, and bears a deep lateral parabolicshaped articulatory facet for the reception of the posterior process of the postorbital. The anteroventral process is very elongate, being much longer than the posteroventral process, with both processes forming a dorsal cap that is likely to have embraced the quadrate-quadratojugal element as in the modern
|
||
<taxonomicName box="[1328,1438,1531,1552]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="3" pageNumber="4" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1328,1438,1531,1552]" italics="true" pageId="3" pageNumber="4">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="3.[810,1472,1336,1972]" pageId="3" pageNumber="4">
|
||
The frontals are paired and are well-preserved along the orbital margins, but their anterior and posterior margins are shattered (
|
||
<figureCitation box="[817,896,1615,1637]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[974,1048,1615,1636]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="3" pageNumber="4">
|
||
<quantity box="[974,1008,1615,1636]" metricMagnitude="0" metricUnit="m" metricValue="3.0" pageId="3" pageNumber="4" unit="m" value="3.0">3m</quantity>
|
||
, n
|
||
</figureCitation>
|
||
). The frontals have greatly elevated anterolateral articulatory facets to receive the prefrontal dorsal process and elongate posteroventrolateral articulatory facets to receive the postfrontal (
|
||
<figureCitation box="[1062,1133,1698,1720]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1194,1221,1699,1720]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="3" pageNumber="4">3o</figureCitation>
|
||
). Both suggest that the frontals contributed little to the dorsal margin of the orbits. On their ventral side, the frontals have weakly developed subolfactory processes. Asmall level of sculpturing is observed on the external surface of the frontals.
|
||
</paragraph>
|
||
<paragraph blockId="3.[810,1472,1336,1972]" lastBlockId="5.[116,779,136,1804]" lastPageId="5" lastPageNumber="6" pageId="3" pageNumber="4">
|
||
The parietals are both poorly preserved and in tight articulation with each other (
|
||
<figureCitation box="[1131,1205,1866,1888]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="3" pageNumber="4">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1270,1305,1866,1887]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="3" pageNumber="4">
|
||
<quantity box="[1270,1305,1866,1887]" metricMagnitude="0" metricUnit="m" metricValue="3.0" pageId="3" pageNumber="4" unit="m" value="3.0">3m</quantity>
|
||
</figureCitation>
|
||
). Although the anterior margin of the left parietal is preserved, it was bent dorsally and thus the nature of its contact with the left frontal cannot be determined. The left element suggests the parietals are broad, resembling the condition on
|
||
<taxonomicName authorityName="von Meyer" authorityYear="1847" box="[477,614,137,158]" class="Reptilia" family="Sphenodontidae" genus="Homeosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[477,614,137,158]" italics="true" pageId="5" pageNumber="6">Homeosaurus</emphasis>
|
||
</taxonomicName>
|
||
(TRS, pers. obs. and34), but this condition may be the result of compression of the specimen. There is no evidence for a developed sagittal crest, suggesting this feature was either absent or weakly developed in MNA.V.12442. Considering the parietals experience a great degree of ontogenetic change in extant and fossil lepidosaurs31,35,36, we consider that additional specimens with undistorted parietals and from a later ontogenetic stage would be necessary to fully understand the morphology of this element. The posterior margin of the parietals is poorly preserved and the contact with the supraoccipital cannot be determined.
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="3" pageNumber="4">
|
||
<paragraph blockId="3.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="3" pageNumber="4">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346794" ID-Zenodo-Dep="6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="4" pageNumber="5" startId="4.[116,146,1553,1572]" targetBox="[171,1417,136,1528]" targetPageId="4">
|
||
<paragraph blockId="4.[116,1473,1552,1851]" pageId="4" pageNumber="5">
|
||
<emphasis bold="true" box="[116,859,1552,1572]" pageId="4" pageNumber="5">
|
||
Fig. 3 Individual elements of the skull of the holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[624,684,1552,1572]" genus="Navajosphenodon" pageId="4" pageNumber="5" rank="species" species="sani">
|
||
<emphasis bold="true" box="[624,684,1552,1572]" italics="true" pageId="4" pageNumber="5">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442). a
|
||
</emphasis>
|
||
Premaxilla in lateral (left) and posterior (right) views.
|
||
<emphasis bold="true" box="[1334,1345,1553,1572]" pageId="4" pageNumber="5">b</emphasis>
|
||
Left maxilla in lateral (left) and medial (right) views.
|
||
<emphasis bold="true" box="[461,471,1581,1600]" pageId="4" pageNumber="5">c</emphasis>
|
||
Left maxilla in occlusal view.
|
||
<emphasis bold="true" box="[739,750,1581,1600]" pageId="4" pageNumber="5">d</emphasis>
|
||
Nasals in dorsal view.
|
||
<emphasis bold="true" box="[959,970,1581,1600]" pageId="4" pageNumber="5">e</emphasis>
|
||
Left prefrontal in lateral (left) and medial (right) views.
|
||
<emphasis bold="true" box="[116,123,1609,1628]" pageId="4" pageNumber="5">f</emphasis>
|
||
Right septomaxilla in ventral view.
|
||
<emphasis bold="true" box="[436,447,1609,1628]" pageId="4" pageNumber="5">g</emphasis>
|
||
Right postfrontal in lateral (left) and medial (right) views.
|
||
<emphasis bold="true" box="[965,976,1609,1628]" pageId="4" pageNumber="5">h</emphasis>
|
||
Right jugal and associated quadratojugal in lateral view.
|
||
<emphasis bold="true" box="[116,122,1637,1656]" pageId="4" pageNumber="5">i</emphasis>
|
||
Fused left quadrate
|
||
<emphasis box="[296,306,1637,1656]" italics="true" pageId="4" pageNumber="5">–</emphasis>
|
||
qudratojugal complex in posterior view.
|
||
<emphasis bold="true" box="[658,664,1637,1656]" pageId="4" pageNumber="5">j</emphasis>
|
||
Left jugal in lateral view.
|
||
<emphasis bold="true" box="[887,898,1637,1656]" pageId="4" pageNumber="5">k</emphasis>
|
||
Right postorbital in medial view.
|
||
<emphasis bold="true" box="[1190,1196,1637,1656]" pageId="4" pageNumber="5">l</emphasis>
|
||
Left postorbital and squamosal in lateral view.
|
||
<emphasis bold="true" box="[252,269,1665,1684]" pageId="4" pageNumber="5">m</emphasis>
|
||
Frontals and parietals in dorsal view.
|
||
<emphasis bold="true" box="[610,621,1665,1684]" pageId="4" pageNumber="5">n</emphasis>
|
||
Frontals in ventral view.
|
||
<emphasis bold="true" box="[847,858,1665,1684]" pageId="4" pageNumber="5">o</emphasis>
|
||
Right frontal in lateral view. Relative bone positions in
|
||
<emphasis bold="true" box="[1353,1364,1665,1684]" pageId="4" pageNumber="5">h</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[1376,1382,1665,1684]" pageId="4" pageNumber="5">l</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[1393,1410,1665,1684]" pageId="4" pageNumber="5">m</emphasis>
|
||
are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<footnote box="[431,1126,2007,2023]" pageId="4" pageNumber="5">
|
||
<paragraph blockId="4.[431,1126,2007,2023]" box="[431,1126,2007,2023]" pageId="4" pageNumber="5">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<paragraph blockId="5.[116,779,136,1804]" pageId="5" pageNumber="6">
|
||
Both palatines are preserved on the ventral side of the skull (
|
||
<figureCitation box="[123,181,471,493]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">Fig. 4</figureCitation>
|
||
), mostly represented by the well-developed single palatine tooth row with teeth of similar size to the anterior teeth in the maxillae and dentaries (
|
||
<figureCitation box="[355,421,527,549]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[472,522,527,549]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">4a, b</figureCitation>
|
||
). The palatine has a welldeveloped dorsal process that contacts the prefrontal dorsally, and the maxilla and jugal laterally. Owing to poor preservation, it is not possible to determine if the palatines met at the midline anteriorly, as in most sphenodontians.
|
||
</paragraph>
|
||
<paragraph blockId="5.[116,779,136,1804]" pageId="5" pageNumber="6">
|
||
The pterygoids are mostly preserved on their posterior portion, including the transverse and the quadrate processes (
|
||
<figureCitation box="[663,731,694,716]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[116,178,722,744]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">4a, b</figureCitation>
|
||
). The transverse process is broad and contacts the ectopterygoid distally, but it is not possible to tell the degree of development of the transverse pterygoid flanges. Both pterygoids have well-developed arcuate flanges on the midline for the articulation with the basipterygoid processes of the basisphenoid. The quadrate processes are elongate and curved posterolaterally, being located medially to the pterygoid process of the quadratequadratojugal. The body of the pterygoid features small denticles organized in at least one dental row.
|
||
</paragraph>
|
||
<paragraph blockId="5.[116,779,136,1804]" pageId="5" pageNumber="6">
|
||
The ectopterygoid is better preserved on the left side of the skull (
|
||
<figureCitation box="[181,263,1001,1023]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2a</figureCitation>
|
||
and
|
||
<figureCitation box="[322,376,1001,1023]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">4a, b</figureCitation>
|
||
). The element is mostly distorted but seems to have had a broad articulation with the transverse process of the pterygoid and a well-developed posterolateral process.
|
||
</paragraph>
|
||
<paragraph blockId="5.[116,779,136,1804]" pageId="5" pageNumber="6">
|
||
The left epipterygoid is preserved ventral to the left parietal and exiting the skull on the space between the left parietal and left postorbital (
|
||
<figureCitation box="[243,314,1141,1163]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[375,400,1141,1162]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">4a</figureCitation>
|
||
). It is delicate and rodlike with an expanded base as in most sphenodontians and early diapsids. The first ceratobranchial is preserved on the right side of the skull extending from the main body of the pterygoids to the posterior end of the right surangular (
|
||
<figureCitation box="[410,469,1252,1274]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Fig. 2</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="5.[116,779,136,1804]" pageId="5" pageNumber="6">
|
||
Very few of the braincase elements are preserved or diagnosable. The most informative component is the basisphenoid, located immediately posterior to the pterygoids and ventrally to the parietals’ posterior margin (
|
||
<figureCitation box="[575,635,1364,1386]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Fig. 2</figureCitation>
|
||
). It has welldeveloped basipterygoid processes with distally expanded elliptical articulatory surfaces for the pterygoids (
|
||
<figureCitation box="[569,661,1419,1442]" captionStart="Fig" captionStartId="6.[116,146,1759,1778]" captionTargetBox="[338,1251,138,1732]" captionTargetId="figure-0@6.[336,1251,135,1735]" captionTargetPageId="6" captionText="Fig. 4 Palatal region and braincase of the holotype of N. sani (MNA.V.12442). Palatal region in dorsal (a) and ventral (b) views. Basisphenoid in ventral (c), dorsal (d), anterior (e), and right lateral (f) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="5" pageNumber="6">Fig. 4c–f</figureCitation>
|
||
). In ventral view, a short cultriform process extends anteriorly and includes a pair of short trabeculae cranii dorsally. A pair of ventral openings represent the entrance of the internal carotids. In dorsal view, the dorsum sellae is exposed forming the posterior margin of a deep pituitary fossa lying on the well-developed sella turcica. Anteriorly, the abducens canals for the cranial nerve VI are located dorsolaterally to the cultriform process and ventrally to the clinoid processes. Overall, these features are similar to the braincase anatomy of many other lepidosaurs, including terrestrial fully-limbed squamates, with the exception of the ventral location of the openings for the carotids37,38. Asmall portion of the basioccipital is preserved in tight articulation with the posterior margin of the basisphenoid.
|
||
</paragraph>
|
||
<paragraph blockId="5.[116,778,1866,1972]" lastBlockId="5.[810,1472,135,1609]" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[116,226,1866,1888]" pageId="5" pageNumber="6">Mandibles</emphasis>
|
||
. Smaller specimens (inferred as juveniles, see below) have a relatively lower degree of ossification and are slender relative to the dentaries of MNA.V.12442 (
|
||
<figureCitation box="[552,611,1921,1944]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">Fig. 5</figureCitation>
|
||
), which in turn, is comparatively slender in relation to the largest specimens (inferred as adults) (see “Ontogeny of jaws and teeth”, below). As in other sphenodontians, the dentaries have a strongly developed and ascending coronoid process, as well as a very elongate posteroventral process extending far posteriorly, to the level of the glenoid in MNA.V.12442 (
|
||
<figureCitation box="[1084,1156,248,270]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">Fig. 5a</figureCitation>
|
||
). The Meckelian canal is open medially and is relatively shallow. The ventral margin of the dentaries curve inwards and upwards creating a ventral crest that forms the ventral border of the Meckelian canal (
|
||
<figureCitation box="[1315,1412,332,354]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">Fig. 5b, c</figureCitation>
|
||
). The dentary symphyses are not clearly visible in most specimens, but in the
|
||
<typeStatus box="[890,980,387,409]" pageId="5" pageNumber="6">holotype</typeStatus>
|
||
, they are small, nearly straight, and slightly expanded dorsoventrally (
|
||
<figureCitation box="[1094,1175,415,437]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">Fig. 5c</figureCitation>
|
||
), thus differing from the strongly curved condition in
|
||
<taxonomicName authorityName="Evans" authorityYear="1980" box="[1131,1280,443,464]" class="Reptilia" family="Gephyrosauridae" genus="Gephyrosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1131,1280,443,464]" italics="true" pageId="5" pageNumber="6">Gephyrosaurus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Whiteside" authorityYear="1986" class="Reptilia" family="Sphenodontidae" genus="Diphydontosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis italics="true" pageId="5" pageNumber="6">Diphydontosaurus</emphasis>
|
||
</taxonomicName>
|
||
(TRS, pers. obs. and refs. 7,29). It is possible that the more robustly built mandibles in the larger specimens would bear a differently shaped symphysis, especially a greater degree of dorsoventral elongation as implied by their comparatively deeper dentary. For details on dental morphology see section “Dentition” below.
|
||
</paragraph>
|
||
<paragraph blockId="5.[810,1472,135,1609]" pageId="5" pageNumber="6">
|
||
The surangular on the right mandible was displaced ventrally relative to the posteroventral process of the dentary, revealing a deep articulatory face for the latter on its lateral surface and indicating that the surangular extended at least to the level of the coronoid process anteriorly (
|
||
<figureCitation box="[1130,1197,750,772]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Fig. 2</figureCitation>
|
||
). The left surangular is preserved in articulation with the other postdentary bones, with only a small portion of it being exposed in medial view. It forms the dorsal margin of the mandibular adductor fossa, and its anterior end ascends dorsally to contribute to the coronoid process (
|
||
<figureCitation box="[899,967,890,912]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1022,1049,889,912]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">5d</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="5.[810,1472,135,1609]" pageId="5" pageNumber="6">
|
||
The coronoid is reduced as in most sphenodontians, contributing only to the anteromedial portion of the coronoid process (the rest composed by the dentary and surangular) (
|
||
<figureCitation box="[817,884,1001,1023]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[937,965,1001,1023]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">5d</figureCitation>
|
||
). The coronoid dorsal process is short and, when in articulation, would not have ascended above the level of the coronoid process of the dentary, thus being mostly hidden in lateral view. An anteromedial and a smaller posterodorsal process are present on the left coronoid, thus contrasting with the condition in
|
||
<taxonomicName box="[950,1060,1141,1162]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[950,1060,1141,1162]" italics="true" pageId="5" pageNumber="6">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
in which those are highly reduced or absent. The prearticular is elongate, contributing to the retroarticular process ventrally and extending anteriorly at least to the level of the coronoid bone—a small anterior fragment likely belonging to the prearticular indicates it could have reached the level of the posteriormost dentary tooth (
|
||
<figureCitation box="[1251,1321,1280,1302]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[1381,1408,1280,1302]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">5d</figureCitation>
|
||
). The prearticular forms the ventral margin of the mandibular adductor fossa and contacts the other postdentary elements ventrally, except for the coronoid. The angular is not preserved in the
|
||
<typeStatus box="[810,900,1392,1414]" pageId="5" pageNumber="6">holotype</typeStatus>
|
||
, but it is slightly exposed in lateral view on MCZ
|
||
<accessionNumber httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101569" pageId="5" pageNumber="6">VP 101569</accessionNumber>
|
||
(
|
||
<figureCitation box="[900,961,1420,1442]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="5" pageNumber="6">Fig. 6</figureCitation>
|
||
). The articular is not fused to any of the other postdentary bones, forming most of the glenoid surface and retroarticular process. It does not have any discernible processes projecting medially or laterally. The dorsal surface of the glenoid has an elongate central ridge for articulation with the quadrate, which would have enabled propalinal movement of the lower jaw (
|
||
<figureCitation box="[817,891,1587,1609]" captionStart="Fig" captionStartId="7.[116,146,521,540]" captionTargetBox="[171,1417,136,496]" captionTargetId="figure-920@7.[170,1418,135,497]" captionTargetPageId="7" captionText="Fig. 5 Mandibles of the holotype of N. sani (MNA.V.12442). Left mandible in lateral view (a) and medial view (b). Right dentary in medial view (c). Left post-dentary bones in dorsal view (d). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (a, b) and 1 mm (c, d)." figureDoi="http://doi.org/10.5281/zenodo.6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="5" pageNumber="6">Fig. 5d</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="5.[810,1472,1670,1972]" pageId="5" pageNumber="6">
|
||
<emphasis bold="true" box="[810,913,1670,1692]" pageId="5" pageNumber="6">Dentition</emphasis>
|
||
. Different dental
|
||
<typeStatus box="[1101,1153,1671,1692]" pageId="5" pageNumber="6">types</typeStatus>
|
||
and their changes throughout ontogeny are discussed below in the section “Ontogeny of jaw and teeth” (
|
||
<figureCitation box="[883,940,1726,1748]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="5" pageNumber="6">Fig. 6</figureCitation>
|
||
). Here we provide additional information pertaining to the individual morphology of distinctive dental
|
||
<typeStatus box="[1326,1380,1755,1776]" pageId="5" pageNumber="6">types</typeStatus>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="5.[810,1472,1670,1972]" lastBlockId="7.[116,779,626,1797]" lastPageId="7" lastPageNumber="8" pageId="5" pageNumber="6">
|
||
The premaxillary teeth are only observed in the
|
||
<typeStatus box="[1384,1471,1782,1804]" pageId="5" pageNumber="6">holotype</typeStatus>
|
||
(
|
||
<figureCitation box="[817,884,1810,1832]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="5" pageNumber="6">Figs. 2</figureCitation>
|
||
and
|
||
<figureCitation box="[939,964,1810,1832]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="5" pageNumber="6">3a</figureCitation>
|
||
), and at this stage, the teeth are fully “acrodont”: they are placed apically and fully ankylosed to the jawbone. Three individual teeth of distinct sizes are preserved on the left premaxilla instead of forming a single chisel-like premaxillary tooth, similar to early forms such as
|
||
<taxonomicName authorityName="Whiteside" authorityYear="1986" box="[1191,1372,1922,1943]" class="Reptilia" family="Sphenodontidae" genus="Diphydontosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1191,1372,1922,1943]" italics="true" pageId="5" pageNumber="6">Diphydontosaurus</emphasis>
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName authorityName="Fraser" authorityYear="1982" class="Reptilia" family="Sphenodontidae" genus="Planocephalosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis italics="true" pageId="5" pageNumber="6">Planocephalosaurus</emphasis>
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName authorityName="Swinton" authorityYear="1939" box="[946,1154,1950,1971]" class="Reptilia" family="Clevosauridae" genus="Clevosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="species" species="hudsoni">
|
||
<emphasis box="[946,1154,1950,1971]" italics="true" pageId="5" pageNumber="6">Clevosaurus hudsoni</emphasis>
|
||
</taxonomicName>
|
||
and also
|
||
<taxonomicName authorityName="von Meyer" authorityYear="1847" box="[1267,1403,1950,1971]" class="Reptilia" family="Sphenodontidae" genus="Homeosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="5" pageNumber="6" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1267,1403,1950,1971]" italics="true" pageId="5" pageNumber="6">Homeosaurus</emphasis>
|
||
</taxonomicName>
|
||
(TRS, pers. obs and refs. 7,27,34,39). No accessory flanges are observed in any premaxillary tooth.
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="5" pageNumber="6">
|
||
<paragraph blockId="5.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="5" pageNumber="6">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346796" ID-Zenodo-Dep="6346796" httpUri="https://zenodo.org/record/6346796/files/figure.png" pageId="6" pageNumber="7" startId="6.[116,146,1759,1778]" targetBox="[338,1251,138,1732]" targetPageId="6">
|
||
<paragraph blockId="6.[116,1473,1759,1862]" pageId="6" pageNumber="7">
|
||
<emphasis bold="true" box="[116,825,1759,1779]" pageId="6" pageNumber="7">
|
||
Fig. 4 Palatal region and braincase of the holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[605,666,1759,1779]" genus="Navajosphenodon" pageId="6" pageNumber="7" rank="species" species="sani">
|
||
<emphasis bold="true" box="[605,666,1759,1779]" italics="true" pageId="6" pageNumber="7">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442).
|
||
</emphasis>
|
||
Palatal region in dorsal (
|
||
<emphasis bold="true" box="[1045,1056,1759,1778]" pageId="6" pageNumber="7">a</emphasis>
|
||
) and ventral (
|
||
<emphasis bold="true" box="[1182,1193,1759,1778]" pageId="6" pageNumber="7">b</emphasis>
|
||
) views. Basisphenoid in ventral (
|
||
<emphasis bold="true" box="[125,135,1787,1806]" pageId="6" pageNumber="7">c</emphasis>
|
||
), dorsal (
|
||
<emphasis bold="true" box="[221,232,1787,1806]" pageId="6" pageNumber="7">d</emphasis>
|
||
), anterior (
|
||
<emphasis bold="true" box="[335,346,1787,1806]" pageId="6" pageNumber="7">e</emphasis>
|
||
), and right lateral (
|
||
<emphasis bold="true" box="[519,526,1787,1806]" pageId="6" pageNumber="7">f</emphasis>
|
||
) views. Arc.Fl. Arcuate flanges, Bpt.Pr. basipterygoid process, Ca.Op. openings for internal carotid arteries, Cl. Pr. clinoid process, Cu.Pr. cultriform process, Do.Se. dorsal sella, L.Pr. lateral process, Pal.Asc.Pr. palatine ascending process, Pal.T. palatine teeth, Ptg.T. pterygoid teeth, Q.Pr. quadrate process, Sel.Tu. sella turcica, Tr.Cr. trabeculae cranii, VI passage for cranial nerve VI (abducens canal). Scale bars = 1 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<footnote box="[431,1126,2007,2023]" pageId="6" pageNumber="7">
|
||
<paragraph blockId="6.[431,1126,2007,2023]" box="[431,1126,2007,2023]" pageId="6" pageNumber="7">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346799" ID-Zenodo-Dep="6346799" httpUri="https://zenodo.org/record/6346799/files/figure.png" pageId="7" pageNumber="8" startId="7.[116,146,521,540]" targetBox="[171,1417,136,496]" targetPageId="7">
|
||
<paragraph blockId="7.[116,1471,520,596]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[116,663,520,540]" pageId="7" pageNumber="8">
|
||
Fig. 5 Mandibles of the holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[442,503,520,540]" genus="Navajosphenodon" pageId="7" pageNumber="8" rank="species" species="sani">
|
||
<emphasis bold="true" box="[442,503,520,540]" italics="true" pageId="7" pageNumber="8">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442).
|
||
</emphasis>
|
||
Left mandible in lateral view (
|
||
<emphasis bold="true" box="[931,942,521,540]" pageId="7" pageNumber="8">a</emphasis>
|
||
) and medial view (
|
||
<emphasis bold="true" box="[1114,1125,521,540]" pageId="7" pageNumber="8">b</emphasis>
|
||
). Right dentary in medial view (
|
||
<emphasis bold="true" box="[1409,1419,521,540]" pageId="7" pageNumber="8">c</emphasis>
|
||
). Left post-dentary bones in dorsal view (
|
||
<emphasis bold="true" box="[429,440,549,568]" pageId="7" pageNumber="8">d</emphasis>
|
||
). Ce.Rd. central ridge, Gl. glenoid articulation, Me.C. Mekelian canal, RAP retroarticular process, San.C.Pr. surangular coronoid process, Sym. symphysis, V.Cr. ventral crest. Scale bars = 10 mm (
|
||
<emphasis bold="true" box="[799,810,577,596]" pageId="7" pageNumber="8">a</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[821,832,577,596]" pageId="7" pageNumber="8">b</emphasis>
|
||
) and 1 mm (
|
||
<emphasis bold="true" box="[949,959,577,596]" pageId="7" pageNumber="8">c</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[970,981,577,596]" pageId="7" pageNumber="8">d</emphasis>
|
||
).
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="7.[116,779,626,1797]" pageId="7" pageNumber="8">
|
||
Nearly all identified maxillae have quite distinct dental regions as typically found in sphenodontines, including large anteriorly located successional teeth, followed distally by a region of hatchling teeth that is heavily worn in most individuals, which in turn is followed distally by an alternating tooth series. The alternating teeth are robust, slightly inclined posteriorly, bearing a single enlarged cusp. Further, alternating teeth include a posteromedially directed dental crest (= dental flange), as also observed in sphenodontines. The additional tooth series is represented by three to five smaller teeth located distally to the alternating tooth series in the smallest individuals (
|
||
<figureCitation box="[511,593,966,988]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">
|
||
Fig.
|
||
<quantity box="[567,593,966,988]" metricMagnitude="-3" metricUnit="kg" metricValue="6.0" pageId="7" pageNumber="8" unit="g" value="6.0">6g</quantity>
|
||
</figureCitation>
|
||
). In the largest individuals (
|
||
<figureCitation box="[244,313,994,1016]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6j</figureCitation>
|
||
), most additional teeth comprise the largest teeth on the tooth row, with the posteriormost two additional teeth being smaller than the anterior ones. The presence of a posteromedially directed flange could not be confirmed on the additional teeth.
|
||
</paragraph>
|
||
<paragraph blockId="7.[116,779,626,1797]" pageId="7" pageNumber="8">
|
||
Dentary teeth include a pair of anteriorly located canine-like successional teeth that represent the largest teeth in the tooth row among the largest individuals (
|
||
<figureCitation box="[437,506,1189,1211]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="7" pageNumber="8">Figs. 2</figureCitation>
|
||
,
|
||
<figureCitation box="[521,533,1189,1210]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="7" pageNumber="8">3</figureCitation>
|
||
, and 6). Distally to the successional teeth, hatchling and alternating teeth occur in the smaller specimens (
|
||
<figureCitation box="[322,422,1245,1267]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6j, k</figureCitation>
|
||
). The latter two dental series are gradually worn away with increasing dentary size (interpreted as an ontogenetic feature, see below), eventually forming an edentulous region where teeth have been completely worn-away, as also observed in the hatchling tooth series and part of the alternating series of
|
||
<taxonomicName box="[322,432,1384,1405]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="7" pageNumber="8" phylum="Chordata" rank="genus">
|
||
<emphasis box="[322,432,1384,1405]" italics="true" pageId="7" pageNumber="8">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<figureCitation box="[445,535,1384,1406]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6e, f</figureCitation>
|
||
) and
|
||
<taxonomicName box="[594,752,1384,1405]" class="Reptilia" family="Sphenodontidae" genus="Cynosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="7" pageNumber="8" phylum="Chordata" rank="genus">
|
||
<emphasis box="[594,752,1384,1405]" italics="true" pageId="7" pageNumber="8">Cynosphenodon</emphasis>
|
||
</taxonomicName>
|
||
14. The alternating teeth are similar in shape to the maxilla alternating teeth, with the larger teeth being robust and conical, but having their distal margin longer than the medial margin, making the teeth look inclined anteriorly when observed in lateral or medial view (
|
||
<figureCitation box="[289,365,1524,1546]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6k</figureCitation>
|
||
). The additional tooth series makes up most of the dentary tooth row in adult individuals (
|
||
<figureCitation box="[652,719,1552,1574]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6l</figureCitation>
|
||
), and similarly to the alternating teeth, appear to be inclined anteriorly due to the more convex distal tooth margin. Further, additional teeth bear an incipient posterior flange, which becomes reduced (possibly due to tooth wear) in older adults (
|
||
<figureCitation box="[561,650,1663,1685]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="7" pageNumber="8">Fig. 6e, f</figureCitation>
|
||
). This flange is much smaller than that observed in young adults of
|
||
<taxonomicName box="[668,778,1691,1712]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="7" pageNumber="8" phylum="Chordata" rank="genus">
|
||
<emphasis box="[668,778,1691,1712]" italics="true" pageId="7" pageNumber="8">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
and other sphenodontines, in which they also become harder to detect in older individuals owing to dental wearing (TRS pers. obs.; FMNH 11113, MCZ VP R4702).
|
||
</paragraph>
|
||
<paragraph blockId="7.[116,778,1862,1968]" lastBlockId="7.[810,1471,631,681]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[116,250,1862,1884]" pageId="7" pageNumber="8">Postcranium</emphasis>
|
||
. The
|
||
<typeStatus box="[312,400,1863,1885]" pageId="7" pageNumber="8">holotype</typeStatus>
|
||
reserves most of the postcranium in full articulation, including vertebrae, ribs, pectoral, and pelvic girdles, as well as fore and hind limbs. All other referred specimens either do not possess postcranial elements, or they are poorly preserved. The postcranium description below is, therefore, entirely based on the
|
||
<typeStatus box="[1087,1175,659,681]" pageId="7" pageNumber="8">holotype</typeStatus>
|
||
(
|
||
<figureCitation box="[1190,1249,659,681]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="7" pageNumber="8">Fig. 7</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="7.[810,1472,722,1972]" pageId="7" pageNumber="8">
|
||
<emphasis bold="true" box="[810,967,722,744]" pageId="7" pageNumber="8">Axial skeleton</emphasis>
|
||
. There are 21 presacral vertebrae preserved, including 4 cervicals and 17 dorsals, but the total number probably reached closer to
|
||
<quantity box="[1035,1086,778,800]" metricMagnitude="-1" metricUnit="m" metricValue="6.35" pageId="7" pageNumber="8" unit="in" value="25.0">25 in</quantity>
|
||
MNA.V.12442 (including at least two additional cervicals). At least one sacral is visible ventral to the pelvic girdle in the CT scans and the pelvic region is followed by eight caudals preserved in partial articulation. The posteriormost caudal region is not preserved in MNA.V.12442.
|
||
</paragraph>
|
||
<paragraph blockId="7.[810,1472,722,1972]" pageId="7" pageNumber="8">
|
||
The atlas and axis are preserved in the
|
||
<typeStatus box="[1253,1341,917,939]" pageId="7" pageNumber="8">holotype</typeStatus>
|
||
(
|
||
<figureCitation box="[1358,1458,917,939]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="7" pageNumber="8">Fig. 7a, b</figureCitation>
|
||
), including an atlas centrum (odontoid) that is not fused to the axial pleurocentrum, which further suggests the juvenile stage of this specimen. The atlas neural arches are preserved dorsal to the axial pleurocentrum, with one of the neural arches broken into two separate components. The axis neural arches were not fused to the centrum body (another juvenile feature). The axis and the third and fourth cervicals have a distinct midventral crest on the ventral side of the centrum, with a pair of nutrient foramina on each side.
|
||
</paragraph>
|
||
<paragraph blockId="7.[810,1472,722,1972]" pageId="7" pageNumber="8">
|
||
Both cervical and dorsal vertebrae are very similar in morphology. The pleurocentra are amphicoelic with deep cotyles and an open notochordal canal, as in most sphenodontians. The cervical and anterior dorsal pleurocentra have elliptical shapes in cross-section at the level of the cotyles, being even narrower on the midpoint of the vertebrae even when discounting some degree of taphonomic deformation. The posterior dorsals have more circular shapes in cross-section and so do the caudal pleurocentra. The ventrolateral sides of the pleurocentra are slightly concave and they meet ventrally forming a midventral crest along the entire vertebral series throughout the dorsal series (
|
||
<figureCitation box="[1380,1452,1475,1497]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="7" pageNumber="8">Fig. 7c</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="7.[810,1472,722,1972]" pageId="7" pageNumber="8">The prezygapophysis and postzygapophysis are well developed, but there are no visible signs of accessory neural arch articulations (zygosphenes-zygantra)—but we note that their presence cannot be entirely excluded. The neural canal is relatively small in diameter and the neural arches at the level of the cervicals have approximately half the height of the pleurocentra. Among the dorsals, the neural arches increase in height, being at least as tall as the pleurocentra. The neural spine is relatively short in the cervical region, becoming much taller in the dorsal region. The diapophyses are connected to the parapophyses by a small ridge, forming an elongate and obliquely oriented synapophysis, as in most other sphenodontians. The intercentra are observed in the cervical region and located in the intervertebral space.</paragraph>
|
||
<paragraph blockId="7.[810,1472,722,1972]" pageId="7" pageNumber="8">
|
||
Caudal vertebrae include mostly the anteriormost region, represented by pygals. Some of the posteriormost pygals include an autotomy septum (
|
||
<figureCitation box="[1038,1136,1922,1944]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="7" pageNumber="8">Fig. 7d, e</figureCitation>
|
||
), which is characteristic of most sphenodontians and squamates.
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="7" pageNumber="8">
|
||
<paragraph blockId="7.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="7" pageNumber="8">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346801" ID-Zenodo-Dep="6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="8" pageNumber="9" startId="8.[116,146,1555,1574]" targetBox="[171,1417,136,1529]" targetPageId="8">
|
||
<paragraph blockId="8.[116,1473,1554,1713]" pageId="8" pageNumber="9">
|
||
<emphasis bold="true" box="[116,833,1554,1574]" pageId="8" pageNumber="9">
|
||
Fig. 6 Conservation of ontogenetic stages from
|
||
<taxonomicName box="[547,703,1554,1574]" genus="Navajosphenodon" pageId="8" pageNumber="9" rank="genus">
|
||
<emphasis bold="true" box="[547,703,1554,1574]" italics="true" pageId="8" pageNumber="9">Navajosphenodon</emphasis>
|
||
</taxonomicName>
|
||
to
|
||
<taxonomicName box="[732,828,1554,1574]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="8" pageNumber="9" phylum="Chordata" rank="genus">
|
||
<emphasis bold="true" box="[732,828,1554,1574]" italics="true" pageId="8" pageNumber="9">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
.
|
||
</emphasis>
|
||
Ontogenetic series on the maxilla (
|
||
<emphasis bold="true" box="[1146,1177,1555,1574]" pageId="8" pageNumber="9">
|
||
a
|
||
<emphasis bold="true" box="[1157,1167,1555,1574]" italics="true" pageId="8" pageNumber="9">–</emphasis>
|
||
c
|
||
</emphasis>
|
||
) and dentary (
|
||
<emphasis bold="true" box="[1308,1336,1555,1574]" pageId="8" pageNumber="9">
|
||
d
|
||
<emphasis bold="true" box="[1320,1330,1555,1574]" italics="true" pageId="8" pageNumber="9">–</emphasis>
|
||
f
|
||
</emphasis>
|
||
) of
|
||
<taxonomicName class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="8" pageNumber="9" phylum="Chordata" rank="species" species="punctatus">Sphenodon punctatus</taxonomicName>
|
||
(rescaled to the same length). Ontogenetic series on the maxilla (
|
||
<emphasis bold="true" box="[799,825,1582,1602]" pageId="8" pageNumber="9">
|
||
g
|
||
<emphasis bold="true" box="[810,820,1583,1602]" italics="true" pageId="8" pageNumber="9">–</emphasis>
|
||
i
|
||
</emphasis>
|
||
) and dentary (
|
||
<emphasis bold="true" box="[961,982,1582,1602]" pageId="8" pageNumber="9">
|
||
j
|
||
<emphasis bold="true" box="[967,977,1583,1602]" italics="true" pageId="8" pageNumber="9">–</emphasis>
|
||
l
|
||
</emphasis>
|
||
) of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1021,1223,1582,1601]" genus="Navajosphenodon" pageId="8" pageNumber="9" rank="species" species="sani">Navajosphenodon sani</taxonomicName>
|
||
. Specimen numbers: FMNH 207433 (
|
||
<emphasis bold="true" box="[200,211,1610,1629]" pageId="8" pageNumber="9">b</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[222,233,1610,1629]" pageId="8" pageNumber="9">e</emphasis>
|
||
); FMNH 11113 (
|
||
<emphasis bold="true" box="[372,382,1610,1629]" pageId="8" pageNumber="9">c</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[392,399,1610,1629]" pageId="8" pageNumber="9">f</emphasis>
|
||
); MCZ VP VP 9094 (
|
||
<emphasis bold="true" box="[596,607,1610,1629]" pageId="8" pageNumber="9">g</emphasis>
|
||
); MCZ VP VP 9100 (
|
||
<emphasis bold="true" box="[801,812,1610,1629]" pageId="8" pageNumber="9">h</emphasis>
|
||
); MCZ VP VP 9093 (
|
||
<emphasis bold="true" box="[1008,1014,1610,1629]" pageId="8" pageNumber="9">i</emphasis>
|
||
); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (
|
||
<emphasis bold="true" box="[856,862,1638,1657]" pageId="8" pageNumber="9">j</emphasis>
|
||
); MNA.V.12442 (
|
||
<emphasis bold="true" box="[1024,1035,1638,1657]" pageId="8" pageNumber="9">k</emphasis>
|
||
); MCZ VP 9093 (
|
||
<emphasis bold="true" box="[1203,1208,1638,1657]" pageId="8" pageNumber="9">l</emphasis>
|
||
).
|
||
<emphasis bold="true" box="[1229,1240,1638,1657]" pageId="8" pageNumber="9">a</emphasis>
|
||
,
|
||
<emphasis bold="true" box="[1251,1262,1638,1657]" pageId="8" pageNumber="9">d</emphasis>
|
||
Re-drawn from ref.
|
||
<bibRefCitation author="Rieppel, O." box="[1446,1465,1635,1650]" journalOrPublisher="J. Herpetol." pageId="8" pageNumber="9" pagination="80 - 84" part="26" refId="ref17595" refString="43. Rieppel, O. The skull in a hatchling of Sphenodon punctatus. J. Herpetol. 26, 80 - 84 (1992)." title="The skull in a hatchling of Sphenodon punctatus" type="journal article" year="1992">
|
||
<superScript attach="right" box="[1446,1465,1635,1650]" fontSize="6" pageId="8" pageNumber="9">43</superScript>
|
||
</bibRefCitation>
|
||
. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="8.[116,778,1750,1967]" pageId="8" pageNumber="9">The cervical and dorsal ribs are elongate, narrow, and occur throughout the entire presacral region with no indication of a lumbar region. Rib heads are wide with poorly differentiated tuberculi and capitula. The anteriormost caudal ribs (pygal region) are fused to the pleurocentra being articulated to synapophyses on the remaining of the caudals.</paragraph>
|
||
<paragraph blockId="8.[116,778,1750,1967]" pageId="8" pageNumber="9">
|
||
There are no traces of a mineralized presternum, but we cannot rule out its presence on the
|
||
<typeStatus box="[408,498,1945,1967]" pageId="8" pageNumber="9">holotype</typeStatus>
|
||
.
|
||
</paragraph>
|
||
<paragraph blockId="8.[810,1472,1750,1967]" lastBlockId="9.[116,778,1554,1966]" lastPageId="9" lastPageNumber="10" pageId="8" pageNumber="9">
|
||
<emphasis bold="true" box="[810,1049,1750,1772]" pageId="8" pageNumber="9">Appendicular skeleton</emphasis>
|
||
. The pectoral girdle is poorly preserved, but remains of both coracoids and scapulae are present (
|
||
<figureCitation box="[1386,1460,1778,1800]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="8" pageNumber="9">Fig. 7h</figureCitation>
|
||
). The scapula is relatively tall, narrow, and straight. The anterior surface of both scapulae is poorly preserved and there are no signs of an anterior emargination. The preserved portion of the coracoids are smaller than the scapulae, do not possess any anterior emarginations, and the supracoracoid foramen is observable in at least one of the preserved elements. The glenoid is well-defined and formed with equal contributions from the scapula and coracoid. There are no traces of an epicoracoid mineralized cartilage associated with the ossifications. No remains of the clavicles and interclavicle were detected. In the pelvic girdle, the left ischium, ilium, and pubis are preserved in close proximity (
|
||
<figureCitation box="[646,718,1665,1687]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">Fig. 7e</figureCitation>
|
||
), and parts of the right pubis and ilium embedded in the matrix were visible through CT scanning (
|
||
<figureCitation box="[422,489,1721,1743]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">Fig. 7i</figureCitation>
|
||
). The pubis is characterized by an obturator foramen close to the acetabulum and a ventrodistally expanding medial margin. The ilium is narrow and elongate with a relatively small iliac blade. The ilium is comprised of a large bony plate, but its medial margin is broken and the presence of an ischiadic tuberosity cannot be assessed.
|
||
</paragraph>
|
||
<footnote box="[431,1126,2007,2023]" pageId="8" pageNumber="9">
|
||
<paragraph blockId="8.[431,1126,2007,2023]" box="[431,1126,2007,2023]" pageId="8" pageNumber="9">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346803" ID-Zenodo-Dep="6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10" startId="9.[116,146,1276,1295]" targetBox="[170,1417,137,1252]" targetPageId="9">
|
||
<paragraph blockId="9.[116,1473,1276,1519]" pageId="9" pageNumber="10">
|
||
<emphasis bold="true" box="[116,773,1276,1296]" pageId="9" pageNumber="10">
|
||
Fig. 7 Postcranial skeleton of the holotype of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[534,596,1276,1296]" genus="Navajosphenodon" pageId="9" pageNumber="10" rank="species" species="sani">
|
||
<emphasis bold="true" box="[534,596,1276,1296]" italics="true" pageId="9" pageNumber="10">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(MNA.V.12442). a
|
||
</emphasis>
|
||
Atlas, axis, and cervical vertebrae 3 and 4 in ventral view.
|
||
<emphasis bold="true" box="[1298,1309,1276,1295]" pageId="9" pageNumber="10">b</emphasis>
|
||
Part of Atlas
|
||
<emphasis box="[1427,1437,1277,1296]" italics="true" pageId="9" pageNumber="10">–</emphasis>
|
||
axis complex in dorsal view.
|
||
<emphasis bold="true" box="[328,338,1304,1323]" pageId="9" pageNumber="10">c</emphasis>
|
||
Dorsal vertebrae in ventral view.
|
||
<emphasis bold="true" box="[634,645,1304,1323]" pageId="9" pageNumber="10">d</emphasis>
|
||
Caudal vertebrae in lateral view.
|
||
<emphasis bold="true" box="[939,950,1304,1323]" pageId="9" pageNumber="10">e</emphasis>
|
||
Pelvic girdle and pygals in ventrolateral view.
|
||
<emphasis bold="true" box="[1355,1362,1304,1323]" pageId="9" pageNumber="10">f</emphasis>
|
||
Right pes in partial articulation.
|
||
<emphasis bold="true" box="[287,298,1332,1351]" pageId="9" pageNumber="10">g</emphasis>
|
||
Left pes with only distal phalanges preserved.
|
||
<emphasis bold="true" box="[712,723,1332,1351]" pageId="9" pageNumber="10">h</emphasis>
|
||
Left scapula and coracoid in lateral view.
|
||
<emphasis bold="true" box="[1094,1100,1332,1351]" pageId="9" pageNumber="10">i</emphasis>
|
||
Right(?) pubis and ilium.
|
||
<emphasis bold="true" box="[1329,1335,1332,1351]" pageId="9" pageNumber="10">j</emphasis>
|
||
Left forearm in posterior view.
|
||
<emphasis bold="true" box="[252,263,1360,1379]" pageId="9" pageNumber="10">k</emphasis>
|
||
Left forearm in anterior view.
|
||
<emphasis bold="true" box="[530,536,1360,1379]" pageId="9" pageNumber="10">l</emphasis>
|
||
Right forearm in anterior view (slightly displaced radius and ulna).
|
||
<emphasis bold="true" box="[1129,1146,1360,1379]" pageId="9" pageNumber="10">m</emphasis>
|
||
Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I
|
||
<emphasis box="[278,288,1500,1519]" italics="true" pageId="9" pageNumber="10">–</emphasis>
|
||
V digit number. Scale bars = 1 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="9.[116,778,1554,1966]" lastBlockId="9.[810,1472,1554,1966]" pageId="9" pageNumber="10">
|
||
Both forelimbs are preserved in close association with the pectoral girdle and to each other (
|
||
<figureCitation box="[464,531,1916,1938]" captionStart="Fig" captionStartId="1.[116,146,1728,1747]" captionTargetBox="[127,767,700,1704]" captionTargetId="figure-719@1.[127,767,700,1704]" captionTargetPageId="1" captionText="Fig. 1 Holotype of Navajosphenodon sani (MNA.V.12442). a As preserved in the sedimentary matrix in ventral view. b Micro CT-scanned and segmented whole skeleton in ventral view; c Micro CT-scanned and segmented whole skeleton in dorsal view (embedded within the sedimentary matrix). Ca.V. caudal vertebrae, Ce.V. cervical vertebrae, Do.V. dorsal vertebrae, Do.R. dorsal ribs, Fe femur, Fi fibula, H humerus, Ma manus, Pe.G. pectoral girdle, Pel.G. pelvic girdle, Ra radius, Ti tibia, Ul ulna. (l) left side and (r) right side. Note: this specimen was previously cataloged as MCZ VP 9016. Scale bar = 10 mm." figureDoi="http://doi.org/10.5281/zenodo.6346786" httpUri="https://zenodo.org/record/6346786/files/figure.png" pageId="9" pageNumber="10">Figs. 1</figureCitation>
|
||
and
|
||
<figureCitation box="[584,638,1915,1938]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">7j–m</figureCitation>
|
||
). The humeri are straight, with their distal ends slightly twisted relative to the proximal ends (at approximately 30°). The proximal ends are poorly preserved, and the shape of the humeral head is not clear, but the deltopectoral crest is moderately developed. The distal end of the humerus is expanded and larger relative to the humeral head, bearing an entepicondylar foramen that is completely open (connecting the ventral and dorsal sides of the humerus) (
|
||
<figureCitation box="[1367,1460,1693,1715]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">Fig. 7l, m</figureCitation>
|
||
). The ectepicondylar foramen is not clearly visible. Amoderately developed capitulum for connection with the radius is observed on the right humerus (
|
||
<figureCitation box="[1004,1103,1777,1799]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">Fig. 7l, m</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="9.[810,1472,1554,1966]" pageId="9" pageNumber="10">
|
||
The radii are slender and elongate, located just next to the preserved ulnae. Their proximal ends have a shallow concavity for articulation with the humeral capitulum. The ulnae have a moderately developed and ossified olecranon process proximally, but their distal ends are not preserved on either side (
|
||
<figureCitation box="[1359,1460,1915,1938]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="9" pageNumber="10">Fig. 7j–m</figureCitation>
|
||
). The ulnae are elongate and stouter than the radii.
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="9" pageNumber="10">
|
||
<paragraph blockId="9.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="9" pageNumber="10">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<paragraph blockId="10.[116,779,136,382]" pageId="10" pageNumber="11">
|
||
The left pes is partially preserved in close proximity to the distal ends of the left tibia and fibula with the proximal part of the astragalus exposed, along with the five metatarsals (
|
||
<figureCitation box="[649,719,192,214]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="10" pageNumber="11">Fig. 7f</figureCitation>
|
||
). The fifth metatarsal is partially obscured by matrix and its head is expanded, but with only a moderate observable degree of inflection, thus constituting a weakly-hooked fifth metatarsal. The right pes is poorly preserved, except by one digit (
|
||
<figureCitation box="[692,766,304,326]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="10" pageNumber="11">
|
||
Fig.
|
||
<quantity box="[740,766,304,325]" metricMagnitude="-3" metricUnit="kg" metricValue="7.0" pageId="10" pageNumber="11" unit="g" value="7.0">7g</quantity>
|
||
</figureCitation>
|
||
), which includes an elongate penultimate phalanx and an ungual phalanx relatively tall (dorsoventrally deep) at its base.
|
||
</paragraph>
|
||
<paragraph blockId="10.[116,778,443,1972]" pageId="10" pageNumber="11">
|
||
<emphasis bold="true" box="[116,426,443,465]" pageId="10" pageNumber="11">Ontogeny of jaws and teeth</emphasis>
|
||
. In hatchlings of
|
||
<taxonomicName box="[625,735,443,464]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[625,735,443,464]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
the dentition is already placed apically and ankylosed to the jaw bones (i.e., acrodont)40–42—although the premaxillary dentition may not yet be entirely ankylosed43 (
|
||
<figureCitation box="[489,584,527,549]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6a, d</figureCitation>
|
||
). In older juveniles and adults, all teeth are externally visible as apically placed and ankylosed to the jaw bones, but it has been previously noted that they appear to be located in shallow sockets in adults—a condition previously termed hyperacrodonty40. Indeed, it was subsequently found in the cross-section of fossil sphenodontians that teeth can be deeply rooted into the jaws, such as in
|
||
<taxonomicName class="Reptilia" family="Sphenodontidae" genus="Cynosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis italics="true" pageId="10" pageNumber="11">Cynosphenodon</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Apesteguia & Novas" authorityYear="2003" box="[277,425,722,743]" class="Insecta" family="Lasiocampidae" genus="Priosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Lepidoptera" pageId="10" pageNumber="11" phylum="Arthropoda" rank="genus">
|
||
<emphasis box="[277,425,722,743]" italics="true" pageId="10" pageNumber="11">Priosphenodon</emphasis>
|
||
</taxonomicName>
|
||
44,45.
|
||
</paragraph>
|
||
<paragraph blockId="10.[116,778,443,1972]" pageId="10" pageNumber="11">
|
||
In terms of replacement patterns, there are five generations of teeth in
|
||
<taxonomicName box="[205,313,778,799]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[205,313,778,799]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
, the first three occurring in the embryo and representing small alternating teeth. The fourth and fifth generations occur after hatching and represent the anteriormost teeth on the mandibles, maxillae, and premaxillae—termed successional (or replacement) teeth7,40–42,46 (
|
||
<figureCitation box="[594,702,889,912]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6b, e</figureCitation>
|
||
). They are larger and so they replace two or more teeth from the previous generation40. Those may fuse to each other in each premaxilla forming a chisel-shaped structure. Some of the hatchling dentition is not replaced in the maxilla, forming a short series of teeth between the larger anterior successional teeth and the subsequent alternating tooth series—termed hatchling teeth. Further posteriorly on the maxilla, small teeth from older generations are kept with larger successional teeth41. These different generations of teeth produce a pattern of alternating teeth7,40–42 (
|
||
<figureCitation box="[661,766,1141,1163]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6b, e</figureCitation>
|
||
). Finally, teeth homogeneous in size are continuously added posteriorly to the lower and upper jaws as they grow and are termed additional teeth (sometimes referred to as uniform teeth)7,40–42,46. This last process begins much earlier in the dentary relative to the maxilla, and consequently, there are more additional teeth on the dentary of adult forms than in the maxilla40 (
|
||
<figureCitation box="[222,314,1335,1358]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6a–f</figureCitation>
|
||
). In embryos, however, the alternating pattern is clearly visible in both upper and lower jaws (
|
||
<figureCitation box="[602,700,1364,1386]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6a, d</figureCitation>
|
||
). Teeth on the mandible grow in proportion to the increase in the length of the jaw47, so the dentary teeth are uniformly increasing in size posteriorly (
|
||
<figureCitation box="[239,332,1447,1470]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6c, f</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="10.[116,778,443,1972]" lastBlockId="10.[810,1472,136,1218]" pageId="10" pageNumber="11">
|
||
The mandibular elements from
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[463,534,1476,1497]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[463,534,1476,1497]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
reported here represent individuals that come from the same locality but are quite variable in size, with the largest individuals having dentary lengths nearly twice the size of the smallest individuals (Supplementary Table 1). Along with additional ontogenetic markers (
|
||
<figureCitation box="[224,293,1615,1637]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6</figureCitation>
|
||
), these specimens are best interpreted as comprising an ontogenetic series. Specifically, the smallest and best-preserved individuals (inferred juveniles) are relatively similar in size and include all dental categories normally recognized in hatchlings and juveniles of
|
||
<taxonomicName box="[577,686,1726,1747]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[577,686,1726,1747]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
: successional, hatchling, alternating, and additional teeth series. Among those, there are several small-sized successional teeth preserved in situ—at least six in MCZ
|
||
<accessionNumber box="[409,522,1810,1832]" httpUri="http://www.ncbi.nlm.nih.gov/nucleotide/VP101569" pageId="10" pageNumber="11">VP 101569</accessionNumber>
|
||
—and space for a similar number of successional teeth in other small individuals—i.e., MCZ VP 9099, 9094, and 101564 (
|
||
<figureCitation box="[486,611,1866,1888]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">
|
||
Fig.
|
||
<quantity box="[534,559,1866,1888]" metricMagnitude="-3" metricUnit="kg" metricValue="6.0" pageId="10" pageNumber="11" unit="g" value="6.0">6g</quantity>
|
||
, h, j
|
||
</figureCitation>
|
||
). The two bestpreserved juveniles (MCZ VP 9099 and 101564) have a short series of hatchling teeth with three or four teeth found in situ (
|
||
<figureCitation box="[123,190,1950,1972]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6j</figureCitation>
|
||
). The alternating tooth series comprises a series of five to seven larger teeth interspaced by smaller teeth. Finally, the additional series in those individuals is comprised of only two to four additional teeth.
|
||
</paragraph>
|
||
<paragraph blockId="10.[810,1472,136,1218]" pageId="10" pageNumber="11">
|
||
The
|
||
<typeStatus box="[892,980,220,242]" pageId="10" pageNumber="11">holotype</typeStatus>
|
||
(MNA.V.12442) is an intermediately sized individual that is ~30% longer than the juvenile dentaries, but less than 50% of the length of the largest dentary (Supplementary Table 1 and
|
||
<figureCitation box="[952,1041,303,326]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6j–l</figureCitation>
|
||
). It has at least five additional teeth, it already demonstrates some degree of tooth wear on the dentary anteriorly, and it bears only two successional teeth on the dentaries (
|
||
<figureCitation box="[914,986,387,409]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6k</figureCitation>
|
||
). As in
|
||
<taxonomicName box="[1063,1173,387,408]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1063,1173,387,408]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
, the maxillae on the
|
||
<typeStatus box="[1383,1471,387,409]" pageId="10" pageNumber="11">holotype</typeStatus>
|
||
retain many teeth from younger ontogenetic stages, thus being composed of a couple of anterior successional teeth, a small section of hatchling teeth, and a posteriorly dominant alternating tooth series (
|
||
<figureCitation box="[953,1062,499,521]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="10" pageNumber="11">Fig. 3b, c</figureCitation>
|
||
). Additionally, this specimen has the odontoid still unfused to the centrum body of the axis, further suggestive of skeletal immaturity (see more below).
|
||
</paragraph>
|
||
<paragraph blockId="10.[810,1472,136,1218]" pageId="10" pageNumber="11">
|
||
The largest individuals (dentaries about twice as long as the juvenile dentaries) have dentaries that are more robustly built and dorsoventrally deep than smaller specimens (
|
||
<figureCitation box="[1315,1391,639,661]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6l</figureCitation>
|
||
). They include a much longer series of additional teeth that form most of the tooth row on both dentaries and maxillae (
|
||
<figureCitation box="[1323,1411,694,716]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6i, l</figureCitation>
|
||
). The anteriormost region of the adult dentaries is not preserved in any specimen, but the anteriormost preserved teeth are much smaller in size compared to the last additional teeth on the tooth row, further suggesting a later ontogenetic stage of these specimens. The anteriormost preserved region of the dentary in MCZ VP 9093 indicates a great degree of tooth wear (being nearly edentulous), and impressions on the sedimentary matrix indicate the presence of two large anterior successional teeth (
|
||
<figureCitation box="[1361,1428,917,939]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6l</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="10.[810,1472,136,1218]" pageId="10" pageNumber="11">
|
||
This pattern of size, bone shape variation, and changes in dental categories observed among all sampled
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1281,1353,974,995]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[1281,1353,974,995]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
individuals thus closely matches the ontogenetic sequence of dentary and maxillary changes in
|
||
<taxonomicName box="[1056,1166,1029,1050]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1056,1166,1029,1050]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
. Most of the isolated jaw elements recovered are, therefore, interpreted as belonging to young juveniles (although no hatchlings seem to be present), some older juveniles intermediate in length between the youngest individuals and adults (e.g., MNA.V.12442), and adult individuals with dental features and dental wearing typically found in older adults of
|
||
<taxonomicName box="[907,1017,1196,1217]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[907,1017,1196,1217]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<figureCitation box="[1032,1091,1196,1218]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Fig. 6</figureCitation>
|
||
).
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection lastPageId="13" lastPageNumber="14" pageId="10" pageNumber="11" type="discussion">
|
||
<paragraph blockId="10.[810,1472,1280,1972]" pageId="10" pageNumber="11">
|
||
<emphasis bold="true" box="[810,1230,1280,1302]" pageId="10" pageNumber="11">Comparative anatomy and taxonomy</emphasis>
|
||
.
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1251,1332,1281,1302]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[1251,1332,1281,1302]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
shares with sphenodontids the straight posterior margin of the quadratequadratojugal complex and the presence of arcuate flanges on the pterygoids. Additionally,
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1081,1160,1364,1385]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[1081,1160,1364,1385]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
shares with sphenodontines the caniniform successional teeth anteriorly on the dentary, the quadrangular shape of the additional teeth bases, and the anterior process of the quadratojugal (further suggestive of a complete lower temporal bar). Further, the worn-out dentition at the position of the hatchling and alternating teeth series on the anterior portion of the maxillae and dentaries among larger sized forms (i.e., adults as defined here) is similar to patterns of dental regionalization and tooth wear observed in
|
||
<taxonomicName box="[1273,1383,1587,1608]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="10" pageNumber="11" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1273,1383,1587,1608]" italics="true" pageId="10" pageNumber="11">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<figureCitation box="[1401,1471,1587,1609]" captionStart="Fig" captionStartId="8.[116,146,1555,1574]" captionTargetBox="[171,1417,136,1529]" captionTargetId="figure-156@8.[170,1418,135,1530]" captionTargetPageId="8" captionText="Fig. 6 Conservation of ontogenetic stages from Navajosphenodon to Sphenodon. Ontogenetic series on the maxilla (a–c) and dentary (d–f) of Sphenodon punctatus (rescaled to the same length). Ontogenetic series on the maxilla (g–i) and dentary (j–l) of Navajosphenodon sani. Specimen numbers: FMNH 207433 (b, e); FMNH 11113 (c, f); MCZ VP VP 9094 (g); MCZ VP VP 9100 (h); MCZ VP VP 9093 (i); MCZ VP VP 101564 (top left), MCZ VP VP 9094 (top right), MCZ VP VP 9099 (bottom left), MCZ VP VP 101569 (bottom right) (j); MNA.V.12442 (k); MCZ VP 9093 (l). a, d Re-drawn from ref. 43. Add.T. additional teeth, Alt.T. alternating teeth, Ang angular, D.C.Pr. dentary coronoid process, D.Po.Pr. dentary posterior process, Ed. edentulous region, Hat.T. Hatchling teeth, M.Pr. mentonian process, Me.C. Meckelian canal, Suc.T. Successional teeth, Worn worn out teeth. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346801" httpUri="https://zenodo.org/record/6346801/files/figure.png" pageId="10" pageNumber="11">Figs. 6</figureCitation>
|
||
and
|
||
<figureCitation box="[857,869,1615,1636]" captionStart="Fig" captionStartId="9.[116,146,1276,1295]" captionTargetBox="[170,1417,137,1252]" captionTargetId="figure-318@9.[170,1418,135,1252]" captionTargetPageId="9" captionText="Fig. 7 Postcranial skeleton of the holotype of N. sani (MNA.V.12442). a Atlas, axis, and cervical vertebrae 3 and 4 in ventral view. b Part of Atlas–axis complex in dorsal view. c Dorsal vertebrae in ventral view. d Caudal vertebrae in lateral view. e Pelvic girdle and pygals in ventrolateral view. f Right pes in partial articulation. g Left pes with only distal phalanges preserved. h Left scapula and coracoid in lateral view. i Right(?) pubis and ilium. j Left forearm in posterior view. k Left forearm in anterior view. l Right forearm in anterior view (slightly displaced radius and ulna). m Right forearm in posterior view. Ace acetabulum, As astragulus, Ax axis, Ax.Ce. axis pleurocentrum, Ax.NS. axis neural spine, At.NA. atlas neural arches, Ca.V. caudal vertebra, Co coracoid, Ce.V. cervical vertebra, Dp.Cr. deltopectoral crest, Ent.Fr. entepicondylar foramen, H humerus, H.H. humeral head, Il ilium, Il.Bl. iliac blade (partially preserved), Is isquium, N.S. neural spine, Obt.Fr. obturator foramen, Od. odontoid (atlas centrum), Ol.Pr. olecranon process, Pn.Ph. penultimate phalanx, Po.No. posterior notch on acetabulum, Pu pubis, Pu.Pr. anterior pubic process, Py pygals, Ra radius, Ra.Cd. radial condyle, Sca scapula, Ul ulna, V.Cr. midventral crest, I–V digit number. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346803" httpUri="https://zenodo.org/record/6346803/files/figure.png" pageId="10" pageNumber="11">7</figureCitation>
|
||
). However,
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1000,1074,1616,1637]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[1000,1074,1616,1637]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
differs from most sphenodontines by retaining the pterygoid dentition, the premaxillary dentition present as discrete elements (instead of a single chisel-shaped tooth on each premaxilla), a posterodorsally elongate process of the premaxilla, and the absence of a dorsolateral concavity on the surface of the postorbital—all more commonly observed among earlier evolving, non-sphenodontid sphenodontians. Finally, the presence of a bifurcated dorsal process of the squamosal is unique to
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[922,997,1839,1860]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="species" species="sani">
|
||
<emphasis box="[922,997,1839,1860]" italics="true" pageId="10" pageNumber="11">N. sani</emphasis>
|
||
</taxonomicName>
|
||
among all sphenodontians currently known. The combination of these features suggests sphenodontine affinities of
|
||
<taxonomicName box="[908,1086,1894,1915]" genus="Navajosphenodon" pageId="10" pageNumber="11" rank="genus">
|
||
<emphasis box="[908,1086,1894,1915]" italics="true" pageId="10" pageNumber="11">Navajosphenodon</emphasis>
|
||
</taxonomicName>
|
||
, but as an early evolving form still retaining plesiomorphic sphenodontian features (confirmed by the phylogenetic analyses— below).
|
||
</paragraph>
|
||
<footnote box="[431,1126,2007,2023]" pageId="10" pageNumber="11">
|
||
<paragraph blockId="10.[431,1126,2007,2023]" box="[431,1126,2007,2023]" pageId="10" pageNumber="11">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<paragraph blockId="11.[116,778,136,744]" pageId="11" pageNumber="12">
|
||
Among other Mesozoic sphenodontines,
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[570,645,137,158]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[570,645,137,158]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
differs from
|
||
<taxonomicName box="[116,274,164,185]" class="Reptilia" family="Sphenodontidae" genus="Cynosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[116,274,164,185]" italics="true" pageId="11" pageNumber="12">Cynosphenodon</emphasis>
|
||
</taxonomicName>
|
||
14,44 by having two caniniform successional teeth, a much reduced mentonian process, and the Meckelian canal curving anteroventrally on the dentary, instead of nearly closed by an expanded ventral crest of the dentary. Compared to
|
||
<taxonomicName box="[116,392,276,297]" class="Reptilia" family="Sphenodontidae" genus="Kawasphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="peligrensis">
|
||
<emphasis box="[116,392,276,297]" italics="true" pageId="11" pageNumber="12">Kawasphenodon peligrensis</emphasis>
|
||
</taxonomicName>
|
||
13 and
|
||
<taxonomicName authorityName="Apesteguia" authorityYear="2005" box="[469,604,277,298]" class="Reptilia" family="Sphenodontidae" genus="Kawasphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="expectatus">
|
||
<emphasis box="[469,604,277,298]" italics="true" pageId="11" pageNumber="12">K. expectatus</emphasis>
|
||
</taxonomicName>
|
||
22,
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[639,713,277,298]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[639,713,277,298]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
has a more smoothly inclined coronoid process of the dentary, an elongate and relatively straight dental margin of the dentary instead of a short and concave dental margin, a much higher tooth count, and a distinct orientation of the dentary teeth (mesiodistally oriented with short posterior flange vs. welldeveloped posterolingually directed flange in
|
||
<taxonomicName authorityName="Apesteguia" authorityYear="2005" class="Reptilia" family="Sphenodontidae" genus="Kawasphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="expectatus">
|
||
<emphasis italics="true" pageId="11" pageNumber="12">Kawasphenodon expectatus</emphasis>
|
||
</taxonomicName>
|
||
).
|
||
<taxonomicName box="[241,419,471,492]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="genus">
|
||
<emphasis box="[241,419,471,492]" italics="true" pageId="11" pageNumber="12">Navajosphenodon</emphasis>
|
||
</taxonomicName>
|
||
differs from
|
||
<taxonomicName authorityName="Reynoso" authorityYear="2005" box="[554,687,471,492]" class="Reptilia" family="Sphenodontidae" genus="Sphenovipera" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[554,687,471,492]" italics="true" pageId="11" pageNumber="12">Sphenovipera</emphasis>
|
||
</taxonomicName>
|
||
15 by the absence of venom grooves on the caniniform successional teeth and an open Meckelian canal anteriorly, instead of closed anteriorly by the contact between the ventral dentary crest and the dorsal dentary crest. Further,
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[457,528,583,604]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[457,528,583,604]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
differs from
|
||
<taxonomicName authorityName="Simpson" authorityYear="1926" class="Reptilia" family="Sphenodontidae" genus="Theretairus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="antiquus">
|
||
<emphasis italics="true" pageId="11" pageNumber="12">Theretairus antiquus</emphasis>
|
||
</taxonomicName>
|
||
48 by having a comparatively much reduced and less pronounced medial curvature of the symphyseal region, two instead of one caniniform successional teeth, and posterior teeth inclined anteriorly in lateral view instead of having an apically projecting cusp with a triangular tooth outline.
|
||
</paragraph>
|
||
<paragraph blockId="11.[116,779,806,1972]" pageId="11" pageNumber="12">
|
||
<emphasis bold="true" box="[116,479,806,828]" pageId="11" pageNumber="12">Phylogeny and divergence times</emphasis>
|
||
. Results from all analyses, including maximum parsimony, non-clock Bayesian inference (BI), and relaxed morphological clock BI with tip dating, all strongly support the placement of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[467,539,890,911]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[467,539,890,911]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
within sphenodontines (
|
||
<figureCitation box="[123,182,917,939]" captionStart="Fig" captionStartId="12.[116,146,1080,1099]" captionTargetBox="[170,1418,135,1056]" captionTargetId="figure-518@12.[170,1418,135,1056]" captionTargetPageId="12" captionText="Fig. 8 Majority rule consensus tree from the relaxed morphological clock Bayesian inference analysis with tip dating. Results indicate the phylogenetic relationships among sphenodontians highlighting the placement of N. sani (in bold), clade posterior probabilities (top node values in bold), and median divergence times (bottom node values). Purple node error bars represent the 95% highest posterior density estimates for divergence times. Skull illustrations (all photos taken by TRS) for each major clade are, from top to bottom, Megachirella wachtleri (Squamata), Clevosaurus brasiliensis (Clevosauridae), Homeosaurus maximiliani (Homeosaurinae), Pleurosaurus gingsburi (Pleurosauridae), Kallimodon pulchellus, Priosphenodon avelasi (Eilenodontinae), and Sphenodon punctatus (Sphenodontinae)." figureDoi="http://doi.org/10.5281/zenodo.6346805" httpUri="https://zenodo.org/record/6346805/files/figure.png" pageId="11" pageNumber="12">Fig. 8</figureCitation>
|
||
and Supplementary
|
||
<figureCitation box="[397,463,917,939]" captionStart="Fig" captionStartId="1.[116,146,1728,1747]" captionTargetBox="[127,767,700,1704]" captionTargetId="figure-719@1.[127,767,700,1704]" captionTargetPageId="1" captionText="Fig. 1 Holotype of Navajosphenodon sani (MNA.V.12442). a As preserved in the sedimentary matrix in ventral view. b Micro CT-scanned and segmented whole skeleton in ventral view; c Micro CT-scanned and segmented whole skeleton in dorsal view (embedded within the sedimentary matrix). Ca.V. caudal vertebrae, Ce.V. cervical vertebrae, Do.V. dorsal vertebrae, Do.R. dorsal ribs, Fe femur, Fi fibula, H humerus, Ma manus, Pe.G. pectoral girdle, Pel.G. pelvic girdle, Ra radius, Ti tibia, Ul ulna. (l) left side and (r) right side. Note: this specimen was previously cataloged as MCZ VP 9016. Scale bar = 10 mm." figureDoi="http://doi.org/10.5281/zenodo.6346786" httpUri="https://zenodo.org/record/6346786/files/figure.png" pageId="11" pageNumber="12">Figs. 1</figureCitation>
|
||
and
|
||
<figureCitation box="[518,531,918,940]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="11" pageNumber="12">2</figureCitation>
|
||
)—the clade inclusive of the modern tuatara (
|
||
<taxonomicName box="[333,549,945,967]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="punctatus">
|
||
<emphasis box="[333,549,945,967]" italics="true" pageId="11" pageNumber="12">Sphenodon punctatus</emphasis>
|
||
</taxonomicName>
|
||
) besides other species from the Mesozoic and early Paleogene. Recovering
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[699,778,974,995]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[699,778,974,995]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
within sphenodontines greatly improved the resolution and support of the two major
|
||
<taxonomicName authorityName="Cope" authorityYear="1869" box="[389,552,1029,1051]" class="Reptilia" family="Sphenodontidae" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="family">Sphenodontidae</taxonomicName>
|
||
clades (Sphenodontinae and Eilenodontinae), besides providing valuable information regarding the skull anatomy in early sphenodontids. As a result, we recover a large number of unambiguous synapomorphies defining Sphenodontinae, which include important skull elements in addition to jaw and dental character states. Unambiguous synapomorphies from the majority rule consensus tree from the morphological clock BI are the presence of nasal foramina; the presence of the anterior process of the quadratojugal; the presence of the posterodorsal process of the coronoid; the presence of anterior caniniform successional teeth; the presence of posterior flanges on the posterior dentary teeth; humeri with an expanded radial condyle.
|
||
</paragraph>
|
||
<paragraph blockId="11.[116,779,806,1972]" lastBlockId="11.[810,1472,136,884]" pageId="11" pageNumber="12">
|
||
The overall tree topology and divergence times using relaxed morphological clock BI with tip-dating has the same structure as the equivalent majority rule consensus tree using the same models of evolution of the first published edition of this dataset19. However, a major difference concerns the placement of
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[532,640,1503,1524]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[532,640,1503,1524]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
from the Late Triassic of
|
||
<collectingCountry box="[229,322,1531,1553]" name="Argentina" pageId="11" pageNumber="12">Argentina</collectingCountry>
|
||
, now strongly supported as an early evolving Eilenodontinae.
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[271,379,1559,1580]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[271,379,1559,1580]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
shares several anatomical affinities with eilenodontines and has been previously recovered either as the sister taxon to eilenodontines or as an early member of this group—e.g., refs. 3,17,49, or as an early sphenodontid, outside Eilenodontinae and Sphenodontinae19,50,51. The previous ambiguous placement of
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
among sphenodontids across various studies is most likely derived from the large amount of missing data constituting most of the sphenodontid fossil species. Until recently, among all sphenodontids, cranial data beyond jaw elements was only available for
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[630,737,1782,1803]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[630,737,1782,1803]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
, the extant
|
||
<taxonomicName box="[180,376,1810,1832]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="punctatus">
|
||
<emphasis box="[180,376,1810,1832]" italics="true" pageId="11" pageNumber="12">Sphenodon punctatus</emphasis>
|
||
</taxonomicName>
|
||
(among sphenodontines), and for the Late Cretaceous
|
||
<taxonomicName authorityName="Apesteguia & Novas" authorityYear="2003" box="[237,372,1838,1859]" class="Insecta" family="Lasiocampidae" genus="Priosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Lepidoptera" pageId="11" pageNumber="12" phylum="Arthropoda" rank="genus">
|
||
<emphasis box="[237,372,1838,1859]" italics="true" pageId="11" pageNumber="12">Priosphenodon</emphasis>
|
||
</taxonomicName>
|
||
(among eilenodontines). The recently published
|
||
<taxonomicName box="[214,327,1866,1887]" class="Reptilia" family="Sphenodontidae" genus="Sphenofontis" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[214,327,1866,1887]" italics="true" pageId="11" pageNumber="12">Sphenofontis</emphasis>
|
||
</taxonomicName>
|
||
, from the Late Jurassic of
|
||
<collectingCountry box="[590,676,1866,1887]" name="Germany" pageId="11" pageNumber="12">Germany</collectingCountry>
|
||
21 has just improved the amount of cranial data available for early sphenodontines, but several aspects of its skull morphology remain unknown pending further preparation or CT scanning. Therefore, the paucity of data for the skull anatomy among early sphenodontines has always imposed a severe constraint on the number of unambiguous synapomorphies recovered for Sphenodontinae, and as a result, the overall number of synapomorphies and support for its sister clade—Eilenodontinae—and internal relationships among early sphenodontids.
|
||
</paragraph>
|
||
<paragraph blockId="11.[810,1472,136,884]" pageId="11" pageNumber="12">
|
||
The exceptional amount of new data on early sphenodontine anatomy provided by
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1030,1100,304,326]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[1030,1100,304,326]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
solves the issues above regarding the phylogenetic reconstruction of early sphenodontids. As a result, the phylogenetic placement of
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[1122,1242,360,381]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1122,1242,360,381]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
is now estimated with strong support (0.94 posterior probability) as the earliest deriving and oldest known eilenodontine. Additionally, node support for
|
||
<taxonomicName authorityName="Cope" authorityYear="1869" box="[810,973,443,465]" class="Reptilia" family="Sphenodontidae" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="family">Sphenodontidae</taxonomicName>
|
||
is also higher than in previous studies (0.8 posterior probability herein vs. <0.6 in ref. 19). Furthermore,
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[810,930,499,520]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[810,930,499,520]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
is considerably older than other eilenodontines (representing the only Triassic taxon of the group), and as a result, the time for the most recent common ancestor (MRCA) of all eilenodontines is pushed back into the Late Triassic (median estimate = 213.5 Mya; 95% HPD = 208.6–222.3) and their split from sphenodontines (the
|
||
<taxonomicName authorityName="Cope" authorityYear="1869" box="[1090,1253,639,661]" class="Reptilia" family="Sphenodontidae" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="family">Sphenodontidae</taxonomicName>
|
||
node) at 223.6 Mya (95% HPD = 212.5–238). This indicates a long gap in the early history of eilenodontines of ~40 Myr, between
|
||
<taxonomicName authorityName="Martinez, Apaldetti, Colombi, Praderio, Fernandez, Santi Malnis, Correa, Abelin & Alcober" authorityYear="2013" box="[1304,1424,694,715]" class="Reptilia" family="Sphenodontidae" genus="Sphenotitan" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1304,1424,694,715]" italics="true" pageId="11" pageNumber="12">Sphenotitan</emphasis>
|
||
</taxonomicName>
|
||
and the subsequent members of the group to appear in the fossil record in the Middle Jurassic (e.g.,
|
||
<taxonomicName authorityName="Rasmussen & Callison" authorityYear="1981" box="[1160,1260,750,771]" class="Insecta" family="Lasiocampidae" genus="Eilenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Lepidoptera" pageId="11" pageNumber="12" phylum="Arthropoda" rank="genus">
|
||
<emphasis box="[1160,1260,750,771]" italics="true" pageId="11" pageNumber="12">Eilenodon</emphasis>
|
||
</taxonomicName>
|
||
) (
|
||
<figureCitation box="[1282,1339,750,772]" captionStart="Fig" captionStartId="12.[116,146,1080,1099]" captionTargetBox="[170,1418,135,1056]" captionTargetId="figure-518@12.[170,1418,135,1056]" captionTargetPageId="12" captionText="Fig. 8 Majority rule consensus tree from the relaxed morphological clock Bayesian inference analysis with tip dating. Results indicate the phylogenetic relationships among sphenodontians highlighting the placement of N. sani (in bold), clade posterior probabilities (top node values in bold), and median divergence times (bottom node values). Purple node error bars represent the 95% highest posterior density estimates for divergence times. Skull illustrations (all photos taken by TRS) for each major clade are, from top to bottom, Megachirella wachtleri (Squamata), Clevosaurus brasiliensis (Clevosauridae), Homeosaurus maximiliani (Homeosaurinae), Pleurosaurus gingsburi (Pleurosauridae), Kallimodon pulchellus, Priosphenodon avelasi (Eilenodontinae), and Sphenodon punctatus (Sphenodontinae)." figureDoi="http://doi.org/10.5281/zenodo.6346805" httpUri="https://zenodo.org/record/6346805/files/figure.png" pageId="11" pageNumber="12">Fig. 8</figureCitation>
|
||
). Finally, the uncertainty around the age estimate for the MRCA of all eilenodontines (95% HPD range = 39.4 Myr in ref. 19) becomes much reduced after the inclusion of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[1248,1331,834,855]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="species" species="sani">
|
||
<emphasis box="[1248,1331,834,855]" italics="true" pageId="11" pageNumber="12">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(95% HPD range = 13.7 Myr—
|
||
<figureCitation box="[1011,1069,862,884]" captionStart="Fig" captionStartId="12.[116,146,1080,1099]" captionTargetBox="[170,1418,135,1056]" captionTargetId="figure-518@12.[170,1418,135,1056]" captionTargetPageId="12" captionText="Fig. 8 Majority rule consensus tree from the relaxed morphological clock Bayesian inference analysis with tip dating. Results indicate the phylogenetic relationships among sphenodontians highlighting the placement of N. sani (in bold), clade posterior probabilities (top node values in bold), and median divergence times (bottom node values). Purple node error bars represent the 95% highest posterior density estimates for divergence times. Skull illustrations (all photos taken by TRS) for each major clade are, from top to bottom, Megachirella wachtleri (Squamata), Clevosaurus brasiliensis (Clevosauridae), Homeosaurus maximiliani (Homeosaurinae), Pleurosaurus gingsburi (Pleurosauridae), Kallimodon pulchellus, Priosphenodon avelasi (Eilenodontinae), and Sphenodon punctatus (Sphenodontinae)." figureDoi="http://doi.org/10.5281/zenodo.6346805" httpUri="https://zenodo.org/record/6346805/files/figure.png" pageId="11" pageNumber="12">Fig. 8</figureCitation>
|
||
and Supplementary
|
||
<figureCitation box="[1284,1343,862,884]" captionStart="Fig" captionStartId="4.[116,146,1553,1572]" captionTargetBox="[171,1417,136,1528]" captionTargetId="figure-1@4.[170,1418,135,1529]" captionTargetPageId="4" captionText="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346794" httpUri="https://zenodo.org/record/6346794/files/figure.png" pageId="11" pageNumber="12">Fig. 3</figureCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph blockId="11.[810,1472,931,1707]" pageId="11" pageNumber="12">
|
||
<emphasis bold="true" box="[810,1411,931,953]" pageId="11" pageNumber="12">Morphological disparity and morphospace occupation</emphasis>
|
||
. The morphospace analysis included nearly all taxa used for the phylogenetic analyses and a subset of characters from the skull and mandibles (see Methods) and indicates a clearly distinct occupation of the cranial morphospace by sphenodontians relative to early lepidosaurs (
|
||
<figureCitation box="[1000,1061,1071,1093]" captionStart="Fig" captionStartId="13.[116,146,804,823]" captionTargetBox="[173,1418,135,777]" captionTargetId="figure-693@13.[170,1418,135,780]" captionTargetPageId="13" captionText="Fig. 9 Phylomorphospace of early lepidosaurs and sphenodontians using discrete morphological characters. Clade “A” refers to the clade recovered by the final analysis (relaxed morphological clock Bayesian inference) both here and in Simões, et al.19, including Homeosaurus, pleurosaurids, and saphaeosaurids. For figures with individual taxon names, see Supplementary Fig. 4. Cyno Cynosphenodon, Kaw Kawasphenodon, Nav Navajosphenodon, Sphe. Sphenodon, Sphf. Sphenofontis." figureDoi="http://doi.org/10.5281/zenodo.6346807" httpUri="https://zenodo.org/record/6346807/files/figure.png" pageId="11" pageNumber="12">Fig. 9</figureCitation>
|
||
). Among sphenodontians, most of the morphospace is occupied by members of Clade “A” of ref. 19, composed of
|
||
<taxonomicName authorityName="von Meyer" authorityYear="1847" box="[951,1088,1127,1148]" class="Reptilia" family="Sphenodontidae" genus="Homeosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[951,1088,1127,1148]" italics="true" pageId="11" pageNumber="12">Homeosaurus</emphasis>
|
||
</taxonomicName>
|
||
, pleurosaurids and saphaeosaurids— this clade was left unnamed because of the uncertainty around the phylogenetic placement of
|
||
<taxonomicName authorityName="von Meyer" authorityYear="1847" box="[1086,1223,1183,1204]" class="Reptilia" family="Sphenodontidae" genus="Homeosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1086,1223,1183,1204]" italics="true" pageId="11" pageNumber="12">Homeosaurus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName authorityName="Cocude-Michel" authorityYear="1963" box="[1277,1394,1182,1203]" class="Reptilia" family="Sphenodontidae" genus="Kallimodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1277,1394,1182,1203]" italics="true" pageId="11" pageNumber="12">Kallimodon</emphasis>
|
||
</taxonomicName>
|
||
among distinct phylogenetic optimality criteria19 (and Suppementary
|
||
<figureCitation box="[810,905,1237,1260]" captionStart-0="Fig" captionStart-1="Fig" captionStart-2="Fig" captionStartId-0="1.[116,146,1728,1747]" captionStartId-1="3.[116,146,1195,1214]" captionStartId-2="4.[116,146,1553,1572]" captionTargetBox-0="[127,767,700,1704]" captionTargetBox-1="[366,1221,139,1169]" captionTargetBox-2="[171,1417,136,1528]" captionTargetId-0="figure-719@1.[127,767,700,1704]" captionTargetId-1="figure-435@3.[362,1226,135,1171]" captionTargetId-2="figure-1@4.[170,1418,135,1529]" captionTargetPageId-0="1" captionTargetPageId-1="3" captionTargetPageId-2="4" captionText-0="Fig. 1 Holotype of Navajosphenodon sani (MNA.V.12442). a As preserved in the sedimentary matrix in ventral view. b Micro CT-scanned and segmented whole skeleton in ventral view; c Micro CT-scanned and segmented whole skeleton in dorsal view (embedded within the sedimentary matrix). Ca.V. caudal vertebrae, Ce.V. cervical vertebrae, Do.V. dorsal vertebrae, Do.R. dorsal ribs, Fe femur, Fi fibula, H humerus, Ma manus, Pe.G. pectoral girdle, Pel.G. pelvic girdle, Ra radius, Ti tibia, Ul ulna. (l) left side and (r) right side. Note: this specimen was previously cataloged as MCZ VP 9016. Scale bar = 10 mm." captionText-1="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." captionText-2="Fig. 3 Individual elements of the skull of the holotype of N. sani (MNA.V.12442). a Premaxilla in lateral (left) and posterior (right) views. b Left maxilla in lateral (left) and medial (right) views. c Left maxilla in occlusal view. d Nasals in dorsal view. e Left prefrontal in lateral (left) and medial (right) views. f Right septomaxilla in ventral view. g Right postfrontal in lateral (left) and medial (right) views. h Right jugal and associated quadratojugal in lateral view. i Fused left quadrate–qudratojugal complex in posterior view. j Left jugal in lateral view. k Right postorbital in medial view. l Left postorbital and squamosal in lateral view. m Frontals and parietals in dorsal view. n Frontals in ventral view. o Right frontal in lateral view. Relative bone positions in h, l, m are as preserved in the specimen. Ant.Pr. anterior process, Av.Pr. anteroventral process, Acr.T. acrodont teeth, Ant.Pr. anterior process, AnL.Pr. anterolateral process, br. broken edge, D.Pr. dorsal process, Di.Pr. distal process, E.N. external nares, J.Ft. facet for jugal, N.Pr. nasal process, P.Pr. posterior process, Pal.Ft. facet for maxillary process of palatine, PFr.Ft. facet for postfrontal, Pm.Cr. posteromedial crest, Pm.Pr. premaxillary process, Po.Ft. facet for postorbital, Po.Pr. postorbital process, PoL.Pr. posterolateral process, PrF.Ft. facet for prefrontal, Pv.Pr. posteroventral process, Q quadrate, Qj quadratojugal, Qj.Fr. quadratojugal foramen, Sof.Pr. subolfactory process, St.Pr. supratemporal process, T.Ap. tooth apex, V.Pr. ventral process, Vl.Pr. ventrolateral process, Vo.Ft. facet for vomeronasal organ. Scale bars = 1 mm." figureDoi-0="http://doi.org/10.5281/zenodo.6346786" figureDoi-1="http://doi.org/10.5281/zenodo.6346790" figureDoi-2="http://doi.org/10.5281/zenodo.6346794" httpUri-0="https://zenodo.org/record/6346786/files/figure.png" httpUri-1="https://zenodo.org/record/6346790/files/figure.png" httpUri-2="https://zenodo.org/record/6346794/files/figure.png" pageId="11" pageNumber="12">Figs. 1–3</figureCitation>
|
||
). The remaining of the morphospace is composed of three smaller clusters comprised of clevosaurids, eilenodontines, and sphenodontines.
|
||
<taxonomicName box="[1051,1229,1294,1315]" genus="Navajosphenodon" pageId="11" pageNumber="12" rank="genus">
|
||
<emphasis box="[1051,1229,1294,1315]" italics="true" pageId="11" pageNumber="12">Navajosphenodon</emphasis>
|
||
</taxonomicName>
|
||
occupies the closest position on the morphospace to
|
||
<taxonomicName box="[1137,1246,1322,1343]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1137,1246,1322,1343]" italics="true" pageId="11" pageNumber="12">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
, as expected given the several shared anatomical features between these two taxa.
|
||
</paragraph>
|
||
<paragraph blockId="11.[810,1472,931,1707]" pageId="11" pageNumber="12">
|
||
Some of these results, especially the distinct region of the morphospace occupied by clevosaurids, are similar to a previous analysis focusing on mandibular disparity data52, with the difference of our sampled South American taxon (
|
||
<taxonomicName box="[1332,1471,1461,1483]" class="Reptilia" family="Sphenodontidae" genus="Cynosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="brasiliensis">
|
||
<emphasis box="[1332,1471,1461,1483]" italics="true" pageId="11" pageNumber="12">C. brasiliensis</emphasis>
|
||
</taxonomicName>
|
||
herein) being closer to European taxa than to the North American taxon (
|
||
<taxonomicName box="[1001,1095,1517,1539]" class="Reptilia" family="Sphenodontidae" genus="Cynosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="species" species="bairdi">
|
||
<emphasis box="[1001,1095,1517,1539]" italics="true" pageId="11" pageNumber="12">C. bairdi</emphasis>
|
||
</taxonomicName>
|
||
) (
|
||
<figureCitation box="[1124,1187,1517,1539]" captionStart="Fig" captionStartId="13.[116,146,804,823]" captionTargetBox="[173,1418,135,777]" captionTargetId="figure-693@13.[170,1418,135,780]" captionTargetPageId="13" captionText="Fig. 9 Phylomorphospace of early lepidosaurs and sphenodontians using discrete morphological characters. Clade “A” refers to the clade recovered by the final analysis (relaxed morphological clock Bayesian inference) both here and in Simões, et al.19, including Homeosaurus, pleurosaurids, and saphaeosaurids. For figures with individual taxon names, see Supplementary Fig. 4. Cyno Cynosphenodon, Kaw Kawasphenodon, Nav Navajosphenodon, Sphe. Sphenodon, Sphf. Sphenofontis." figureDoi="http://doi.org/10.5281/zenodo.6346807" httpUri="https://zenodo.org/record/6346807/files/figure.png" pageId="11" pageNumber="12">Fig. 9</figureCitation>
|
||
). We also find the South African specimen (
|
||
<emphasis box="[1009,1025,1545,1566]" italics="true" pageId="11" pageNumber="12">C</emphasis>
|
||
. sp. SAM) to be the most distinct among clevosaurids. Importantly, the biggest difference to previous results using mandibular data is on the peripheral placement of sphenodontines, instead of falling closer to the center of the morphospace and close to
|
||
<taxonomicName authorityName="W.E.Swinton" authorityYear="1939" box="[1083,1203,1657,1678]" class="Reptilia" family="Clevosauridae" genus="Clevosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="11" pageNumber="12" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1083,1203,1657,1678]" italics="true" pageId="11" pageNumber="12">Clevosaurus</emphasis>
|
||
</taxonomicName>
|
||
and other Triassic taxa as in ref. 50.
|
||
</paragraph>
|
||
<paragraph blockId="11.[810,1471,1754,1972]" lastBlockId="12.[116,778,1269,1965]" lastPageId="12" lastPageNumber="13" pageId="11" pageNumber="12">
|
||
<emphasis bold="true" box="[810,1058,1754,1776]" pageId="11" pageNumber="12">Functional morphology</emphasis>
|
||
. Despite an overall pattern of decreasing rates of morphological and molecular change throughout sphenodontian evolution19,24, a large variety of skull shapes can be found throughout the sphenodontian fossil record20 (see also
|
||
<figureCitation box="[810,920,1865,1888]" captionStart-0="Fig" captionStart-1="Fig" captionStart-2="Fig" captionStartId-0="12.[116,146,1080,1099]" captionStartId-1="13.[116,146,804,823]" captionStartId-2="14.[116,146,923,942]" captionTargetBox-0="[170,1418,135,1056]" captionTargetBox-1="[173,1418,135,777]" captionTargetBox-2="[363,1223,137,897]" captionTargetId-0="figure-518@12.[170,1418,135,1056]" captionTargetId-1="figure-693@13.[170,1418,135,780]" captionTargetId-2="figure-534@14.[362,1226,135,899]" captionTargetPageId-0="12" captionTargetPageId-1="13" captionTargetPageId-2="14" captionText-0="Fig. 8 Majority rule consensus tree from the relaxed morphological clock Bayesian inference analysis with tip dating. Results indicate the phylogenetic relationships among sphenodontians highlighting the placement of N. sani (in bold), clade posterior probabilities (top node values in bold), and median divergence times (bottom node values). Purple node error bars represent the 95% highest posterior density estimates for divergence times. Skull illustrations (all photos taken by TRS) for each major clade are, from top to bottom, Megachirella wachtleri (Squamata), Clevosaurus brasiliensis (Clevosauridae), Homeosaurus maximiliani (Homeosaurinae), Pleurosaurus gingsburi (Pleurosauridae), Kallimodon pulchellus, Priosphenodon avelasi (Eilenodontinae), and Sphenodon punctatus (Sphenodontinae)." captionText-1="Fig. 9 Phylomorphospace of early lepidosaurs and sphenodontians using discrete morphological characters. Clade “A” refers to the clade recovered by the final analysis (relaxed morphological clock Bayesian inference) both here and in Simões, et al.19, including Homeosaurus, pleurosaurids, and saphaeosaurids. For figures with individual taxon names, see Supplementary Fig. 4. Cyno Cynosphenodon, Kaw Kawasphenodon, Nav Navajosphenodon, Sphe. Sphenodon, Sphf. Sphenofontis." captionText-2="Fig. 10 Evolutionary changes on the temporal region of sphenodontians. Many early-evolving lepidosaurs retain a single temporal fenestration as the jugal (cyan) does not contact the quadrate/quadratojugal (green) posteriorly. A full development of the lower temporal bar and double temporal fenestration evolved independently at least twice in sphenodontians, once among clevosaurids and once in sphenodontines—an adaptation for stabilizing the quadrate and reducing overall stress in the skull during hard biting58. The latter is unique among lepidosaurs by including contributions from both the jugal and quadratojugal—a morphology convergent with many non-lepidosaurian early diapsid reptiles. Red circle, complete lower temporal bar; blue circle: incomplete lower temporal bar; blue-red gradient circle, lower temporal bar incomplete in juveniles but complete in adults. Skull drawings from top to bottom: Gephyrosaurus (drawn by TRS based on ref. 20), Megachirella (re-drawn by TRS from ref. 33), Diphydontosaurus (drawn by TRS based on ref. 20), Clevosaurus (drawn by TRS based on ref. 20), Palaeopleurosaurus (drawn by TRS based on ref. 20), Navajosphenodon (drawn by A. Brum), and Sphenodon (drawn by TRS based on MCZ R4702)." figureDoi-0="http://doi.org/10.5281/zenodo.6346805" figureDoi-1="http://doi.org/10.5281/zenodo.6346807" figureDoi-2="http://doi.org/10.5281/zenodo.6346809" httpUri-0="https://zenodo.org/record/6346805/files/figure.png" httpUri-1="https://zenodo.org/record/6346807/files/figure.png" httpUri-2="https://zenodo.org/record/6346809/files/figure.png" pageId="11" pageNumber="12">Figs. 8–10</figureCitation>
|
||
). An important component of this variation can be found in the temporal region of the sphenodontian skull, which houses and protects most of the adductor muscles responsible for the closure of the jaw in all lepidosaurs, including
|
||
<taxonomicName box="[116,226,1274,1295]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[116,226,1274,1295]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
47,53,54. Specifically, the posteroventral process of the jugal forms the lower temporal bar delimiting the lower temporal fenestra, and it undergoes a quite strong degree of variation among sphenodontians, both through ontogeny7,27,39 and across evolution20 (
|
||
<figureCitation box="[243,312,1386,1408]" captionStart="Fig" captionStartId="14.[116,146,923,942]" captionTargetBox="[363,1223,137,897]" captionTargetId="figure-534@14.[362,1226,135,899]" captionTargetPageId="14" captionText="Fig. 10 Evolutionary changes on the temporal region of sphenodontians. Many early-evolving lepidosaurs retain a single temporal fenestration as the jugal (cyan) does not contact the quadrate/quadratojugal (green) posteriorly. A full development of the lower temporal bar and double temporal fenestration evolved independently at least twice in sphenodontians, once among clevosaurids and once in sphenodontines—an adaptation for stabilizing the quadrate and reducing overall stress in the skull during hard biting58. The latter is unique among lepidosaurs by including contributions from both the jugal and quadratojugal—a morphology convergent with many non-lepidosaurian early diapsid reptiles. Red circle, complete lower temporal bar; blue circle: incomplete lower temporal bar; blue-red gradient circle, lower temporal bar incomplete in juveniles but complete in adults. Skull drawings from top to bottom: Gephyrosaurus (drawn by TRS based on ref. 20), Megachirella (re-drawn by TRS from ref. 33), Diphydontosaurus (drawn by TRS based on ref. 20), Clevosaurus (drawn by TRS based on ref. 20), Palaeopleurosaurus (drawn by TRS based on ref. 20), Navajosphenodon (drawn by A. Brum), and Sphenodon (drawn by TRS based on MCZ R4702)." figureDoi="http://doi.org/10.5281/zenodo.6346809" httpUri="https://zenodo.org/record/6346809/files/figure.png" pageId="12" pageNumber="13">Fig. 10</figureCitation>
|
||
). The lower temporal bar restricts the possible size of the external mandibular adductors, and so it has a direct impact on the biting force of lepidosaurs. In fact, the reduction or complete loss of the lower temporal bar in lepidosaurs (most notably its complete loss among the vast majority of squamates) has been considered to be one of their major functional advantages relative to other reptiles55, as it enabled the expansion of the
|
||
<emphasis box="[116,600,1581,1603]" italics="true" pageId="12" pageNumber="13">
|
||
<taxonomicName box="[116,383,1581,1603]" class="Reptilia" family="Scincidae" genus="Megachirella" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="12" pageNumber="13" phylum="Chordata" rank="subSpecies" species="adductor" subSpecies="mandibularis">M. adductor mandibularis</taxonomicName>
|
||
externus superficialis
|
||
</emphasis>
|
||
, which generates significantly more powerful bite forces than in similar sized reptiles with a complete lower temporal bar56,57.
|
||
</paragraph>
|
||
<footnote box="[684,1378,2007,2023]" pageId="11" pageNumber="12">
|
||
<paragraph blockId="11.[684,1378,2007,2023]" box="[684,1378,2007,2023]" pageId="11" pageNumber="12">(2022) 5:195 | https://doi.org/10.1038/s42003-022-03144-y | www.nature.com/commsbio</paragraph>
|
||
</footnote>
|
||
<caption ID-DOI="http://doi.org/10.5281/zenodo.6346805" ID-Zenodo-Dep="6346805" httpUri="https://zenodo.org/record/6346805/files/figure.png" pageId="12" pageNumber="13" startId="12.[116,146,1080,1099]" targetBox="[170,1418,135,1056]" targetPageId="12">
|
||
<paragraph blockId="12.[116,1471,1080,1239]" pageId="12" pageNumber="13">
|
||
<emphasis bold="true" box="[116,1177,1080,1099]" pageId="12" pageNumber="13">Fig. 8 Majority rule consensus tree from the relaxed morphological clock Bayesian inference analysis with tip dating.</emphasis>
|
||
Results indicate the phylogenetic relationships among sphenodontians highlighting the placement of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[716,775,1107,1127]" genus="Navajosphenodon" pageId="12" pageNumber="13" rank="species" species="sani">
|
||
<emphasis box="[716,775,1107,1127]" italics="true" pageId="12" pageNumber="13">N. sani</emphasis>
|
||
</taxonomicName>
|
||
(in bold), clade posterior probabilities (top node values in bold), and median divergence times (bottom node values). Purple node error bars represent the 95% highest posterior density estimates for divergence times. Skull illustrations (all photos taken by TRS) for each major clade are, from top to bottom,
|
||
<taxonomicName authorityName="Renesto & Posenato" authorityYear="2003" box="[878,1066,1163,1183]" class="Reptilia" family="Scincidae" genus="Megachirella" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="wachtleri">
|
||
<emphasis box="[878,1066,1163,1183]" italics="true" pageId="12" pageNumber="13">Megachirella wachtleri</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<taxonomicName authorityName="Oppel" authorityYear="1811" box="[1078,1175,1164,1183]" class="Reptilia" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="12" pageNumber="13" phylum="Chordata" rank="order">Squamata</taxonomicName>
|
||
),
|
||
<taxonomicName authorityName="Bonaparte & Sues" authorityYear="2006" box="[1189,1384,1163,1183]" class="Reptilia" family="Clevosauridae" genus="Clevosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="brasiliensis">
|
||
<emphasis box="[1189,1384,1163,1183]" italics="true" pageId="12" pageNumber="13">Clevosaurus brasiliensis</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<taxonomicName authorityName="Fraser" authorityYear="1993" box="[121,254,1192,1211]" class="Reptilia" family="Clevosauridae" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="family">Clevosauridae</taxonomicName>
|
||
),
|
||
<taxonomicName authority="(Homeosaurinae)" baseAuthorityName="Homeosaurinae" box="[269,647,1191,1211]" class="Reptilia" family="Sphenodontidae" genus="Homeosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="maximiliani">
|
||
<emphasis box="[269,483,1191,1211]" italics="true" pageId="12" pageNumber="13">Homeosaurus maximiliani</emphasis>
|
||
(Homeosaurinae)
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName box="[656,842,1191,1211]" class="Reptilia" family="Pleurosauridae" genus="Pleurosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="gingsburi">
|
||
<emphasis box="[656,842,1191,1211]" italics="true" pageId="12" pageNumber="13">Pleurosaurus gingsburi</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<taxonomicName authorityName="Lydekker" authorityYear="1888" box="[854,994,1192,1211]" class="Reptilia" family="Pleurosauridae" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="family">Pleurosauridae</taxonomicName>
|
||
),
|
||
<taxonomicName baseAuthorityName="Zittel" baseAuthorityYear="1887" box="[1008,1187,1191,1211]" class="Reptilia" family="Sphenodontidae" genus="Kallimodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="pulchellus">
|
||
<emphasis box="[1008,1187,1191,1211]" italics="true" pageId="12" pageNumber="13">Kallimodon pulchellus</emphasis>
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName authority="(Eilenodontinae)" baseAuthorityName="Eilenodontinae" class="Insecta" family="Lasiocampidae" genus="Priosphenodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Lepidoptera" pageId="12" pageNumber="13" phylum="Arthropoda" rank="species" species="avelasi">
|
||
<emphasis box="[1199,1382,1191,1211]" italics="true" pageId="12" pageNumber="13">Priosphenodon avelasi</emphasis>
|
||
(Eilenodontinae)
|
||
</taxonomicName>
|
||
, and
|
||
<taxonomicName authority="(Sphenodontinae)" baseAuthorityName="Sphenodontinae" box="[313,659,1219,1239]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="punctatus">
|
||
<emphasis box="[313,492,1219,1239]" italics="true" pageId="12" pageNumber="13">Sphenodon punctatus</emphasis>
|
||
(Sphenodontinae)
|
||
</taxonomicName>
|
||
.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph blockId="12.[116,778,1269,1965]" lastBlockId="12.[810,1472,1269,1965]" pageId="12" pageNumber="13">
|
||
A reduced lower temporal bar has long been known to be the plesiomorphic condition for sphenodontians, with the complete lower temporal bar in
|
||
<taxonomicName box="[354,464,1720,1741]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[354,464,1720,1741]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
representing a reversal to the ancestral diapsid condition58,59. Despite the functional advantage of completely losing the lower temporal bar, its reacquisition in
|
||
<taxonomicName box="[116,226,1804,1825]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[116,226,1804,1825]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
has been considered an important adaptation for stabilizing the quadrate and reducing the overall stress in the skull during hard biting58. Interestingly,
|
||
<taxonomicName box="[494,604,1860,1881]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[494,604,1860,1881]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
is not the only sphenodontian with a reversal to a complete lower temporal bar, as it also happened independently in adults of at least some species of
|
||
<taxonomicName authorityName="W.E.Swinton" authorityYear="1939" box="[238,358,1943,1964]" class="Reptilia" family="Clevosauridae" genus="Clevosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[238,358,1943,1964]" italics="true" pageId="12" pageNumber="13">Clevosaurus</emphasis>
|
||
</taxonomicName>
|
||
27(
|
||
<figureCitation box="[384,463,1943,1965]" captionStart="Fig" captionStartId="14.[116,146,923,942]" captionTargetBox="[363,1223,137,897]" captionTargetId="figure-534@14.[362,1226,135,899]" captionTargetPageId="14" captionText="Fig. 10 Evolutionary changes on the temporal region of sphenodontians. Many early-evolving lepidosaurs retain a single temporal fenestration as the jugal (cyan) does not contact the quadrate/quadratojugal (green) posteriorly. A full development of the lower temporal bar and double temporal fenestration evolved independently at least twice in sphenodontians, once among clevosaurids and once in sphenodontines—an adaptation for stabilizing the quadrate and reducing overall stress in the skull during hard biting58. The latter is unique among lepidosaurs by including contributions from both the jugal and quadratojugal—a morphology convergent with many non-lepidosaurian early diapsid reptiles. Red circle, complete lower temporal bar; blue circle: incomplete lower temporal bar; blue-red gradient circle, lower temporal bar incomplete in juveniles but complete in adults. Skull drawings from top to bottom: Gephyrosaurus (drawn by TRS based on ref. 20), Megachirella (re-drawn by TRS from ref. 33), Diphydontosaurus (drawn by TRS based on ref. 20), Clevosaurus (drawn by TRS based on ref. 20), Palaeopleurosaurus (drawn by TRS based on ref. 20), Navajosphenodon (drawn by A. Brum), and Sphenodon (drawn by TRS based on MCZ R4702)." figureDoi="http://doi.org/10.5281/zenodo.6346809" httpUri="https://zenodo.org/record/6346809/files/figure.png" pageId="12" pageNumber="13">Fig. 10</figureCitation>
|
||
), and possibly in adults of
|
||
<taxonomicName authorityName="Fraser" authorityYear="1982" box="[810,1007,1274,1295]" class="Reptilia" family="Sphenodontidae" genus="Planocephalosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[810,1007,1274,1295]" italics="true" pageId="12" pageNumber="13">Planocephalosaurus</emphasis>
|
||
</taxonomicName>
|
||
39. This reversal also happened (once again, convergently) in two late Cretaceous borioteiioid squamates,
|
||
<emphasis box="[810,1022,1330,1351]" italics="true" pageId="12" pageNumber="13">Tyaniusaurus zhengi</emphasis>
|
||
60 and
|
||
<taxonomicName box="[1101,1386,1330,1351]" class="Reptilia" family="Teiidae" genus="Polyglyphanodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Squamata" pageId="12" pageNumber="13" phylum="Chordata" rank="species" species="stermbergi">
|
||
<emphasis box="[1101,1386,1330,1351]" italics="true" pageId="12" pageNumber="13">Polyglyphanodon stermbergi</emphasis>
|
||
</taxonomicName>
|
||
31— the only lizards to have ever re-evolved a completely enclosed lower temporal fenestra31. However, differently from the condition observed in most other diapsids, the lower temporal bar in lepidosaurs is almost invariably formed by a posterior elongation of the jugal bone only, which contacts the quadrate (in squamates) or the fused quadrate-quadratojugal (in sphenodontians) by either sutural or ligamentous connections31,60.
|
||
</paragraph>
|
||
<paragraph blockId="12.[810,1472,1269,1965]" lastBlockId="13.[116,778,942,1132]" lastPageId="13" lastPageNumber="14" pageId="12" pageNumber="13">
|
||
The only known exception to this rule among lepidosaurs is
|
||
<taxonomicName box="[810,920,1581,1602]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[810,920,1581,1602]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
, in which the quadratojugal has an anterior extension forming a sutural contact with the jugal and contributing to the enclosure of the lower temporal fenestra, as also observed in archosaurs and other diapsid reptiles with double temporal fenestration. We note, however, that the anterior process of the quadratojugal in
|
||
<taxonomicName box="[985,1095,1720,1741]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[985,1095,1720,1741]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
is shorter compared to that of other diapsids61. Yet,
|
||
<taxonomicName box="[968,1078,1748,1769]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[968,1078,1748,1769]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
has been the only lepidosaur known to date with an anatomical reversal to the early diapsid configuration of the temporal region. Therefore, an important question remains on whether the reacquisition of the early diapsid-type temporal region of
|
||
<taxonomicName box="[1002,1112,1860,1881]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1002,1112,1860,1881]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
is an oddity of this taxon among all lepidosaurs currently known (either living or extinct), or if it is a general feature of the
|
||
<taxonomicName box="[1050,1160,1916,1937]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="12" pageNumber="13" phylum="Chordata" rank="genus">
|
||
<emphasis box="[1050,1160,1916,1937]" italics="true" pageId="12" pageNumber="13">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
evolutionary branch, but for which we lack informative fossils. As illustrated here by the temporal configuration of
|
||
<taxonomicName authorityName="Simões & Kinney-Broderick & Pierce" authorityYear="2022" box="[395,471,943,964]" genus="Navajosphenodon" pageId="13" pageNumber="14" rank="species" species="sani">
|
||
<emphasis box="[395,471,943,964]" italics="true" pageId="13" pageNumber="14">N. sani</emphasis>
|
||
</taxonomicName>
|
||
, (
|
||
<figureCitation box="[494,555,942,964]" captionStart="Fig" captionStartId="3.[116,146,1195,1214]" captionTargetBox="[366,1221,139,1169]" captionTargetId="figure-435@3.[362,1226,135,1171]" captionTargetPageId="3" captionText="Fig. 2 Micro CT-scanned and fully segmented skull and mandibles of the holotype of N. sani (MNA.V.12442). a Right ventrolateral view. b Left dorsolateral view. Art articular, Boc basioccipital, Bsp basisphenoid, C coronoid, CbI first ceratobranchial, D dentary, Ect ectopterygoid, Epi epipterygoid, F frontal, J jugal, M maxilla, N nasal, P parietal, Pal palatine, PFr postfrontal, PM premaxilla, Po postorbital, Pra prearticular, PrF prefrontal, Ptg pterygoid, Q-Qj quadrate-quadratojugal, San surangular, Spm septomaxilla, Sq squamosal, (l) left side and (r) right side. Scale bar = 1 mm." figureDoi="http://doi.org/10.5281/zenodo.6346790" httpUri="https://zenodo.org/record/6346790/files/figure.png" pageId="13" pageNumber="14">Fig. 2</figureCitation>
|
||
), it is clear that this condition is not unique to
|
||
<taxonomicName box="[412,522,970,991]" class="Reptilia" family="Sphenodontidae" genus="Sphenodon" kingdom="Animalia" order="Rhynchocephalia" pageId="13" pageNumber="14" phylum="Chordata" rank="genus">
|
||
<emphasis box="[412,522,970,991]" italics="true" pageId="13" pageNumber="14">Sphenodon</emphasis>
|
||
</taxonomicName>
|
||
only, but most likely a broader feature of all sphenodontines, potentially originating at least as far back as the Early Jurassic. It also directly implies that stabilization of the quadrate and overall stress reduction in the skull during hard biting58 has much deeper evolutionary origins than previously thought.
|
||
</paragraph>
|
||
</subSubSection>
|
||
</treatment>
|
||
</document> |