631 lines
100 KiB
XML
631 lines
100 KiB
XML
<document id="0CD2C4215E298B653B812A005BDA713D" ID-DOI="10.4202/app.00915.2021" ID-ISSN="1732-2421" ID-Zenodo-Dep="10981077" IM.bibliography_approvedBy="felipe" IM.illustrations_approvedBy="felipe" IM.materialsCitations_approvedBy="felipe" IM.metadata_approvedBy="felipe" IM.taxonomicNames_approvedBy="felipe" IM.treatments_approvedBy="felipe" checkinTime="1713284933167" checkinUser="felipe" docAuthor="Roberts, Aubrey Jane, Engelschiøn, Victoria Sjøholt & Hurum, Jørn Harald" docDate="2022" docId="03F787E94F28FFB3FC9BFD58656CC957" docLanguage="en" docName="ActaPalaeontolPol.67.1.51-62.pdf" docOrigin="Acta Palaeontologica Polonica 67 (1)" docSource="http://dx.doi.org/10.4202/app.00915.2021" docStyle="DocumentStyle:E4780F6D34569985EDF9CACFB9BC780E.2:ActaPalaeontolPol.2015-.journal_article" docStyleId="E4780F6D34569985EDF9CACFB9BC780E" docStyleName="ActaPalaeontolPol.2015-.journal_article" docStyleVersion="2" docTitle="Phalarodon fraasi Merriam 1910" docType="treatment" docVersion="4" lastPageNumber="58" masterDocId="FFCEFF914F2BFFB4FFB3FFDA6031CD1E" masterDocTitle="First three-dimensional skull of the Middle Triassic mixosaurid ichthyosaur Phalarodon fraasi from Svalbard, Norway" masterLastPageNumber="62" masterPageNumber="51" pageNumber="54" updateTime="1713379104591" updateUser="felipe" zenodo-license-document="CC-BY-4.0">
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<mods:title id="D4FC0FA08D3AC9F1F1D5721536986544">First three-dimensional skull of the Middle Triassic mixosaurid ichthyosaur Phalarodon fraasi from Svalbard, Norway</mods:title>
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<mods:namePart id="C1C76ACD4DE13F880F50EF3E8A7FABD6">Roberts, Aubrey Jane</mods:namePart>
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<mods:namePart id="F03C23096AD7603902F80F911AA066E1">Engelschiøn, Victoria Sjøholt</mods:namePart>
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<mods:namePart id="45EDC27CDF454B73D7CFC38BCA2D6C11">Hurum, Jørn Harald</mods:namePart>
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<mods:title id="C38B16B178512ADDF4BBF0F59E22B07B">Acta Palaeontologica Polonica</mods:title>
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<mods:date id="1F780EDFB5DC970CF07BEE4E649C9C14">2022</mods:date>
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<treatment id="03F787E94F28FFB3FC9BFD58656CC957" LSID="urn:lsid:plazi:treatment:03F787E94F28FFB3FC9BFD58656CC957" httpUri="http://treatment.plazi.org/id/03F787E94F28FFB3FC9BFD58656CC957" lastPageId="7" lastPageNumber="58" pageId="3" pageNumber="54">
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<subSubSection id="C34465744F28FFB7FC9BFD5864EBCF81" box="[808,1242,642,671]" pageId="3" pageNumber="54" type="nomenclature">
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<paragraph id="8BE136FF4F28FFB7FC9BFD5864EBCF81" blockId="3.[808,1242,642,671]" box="[808,1242,642,671]" pageId="3" pageNumber="54">
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<heading id="D0A981934F28FFB7FC9BFD5864EBCF81" box="[808,1242,642,671]" fontSize="12" level="2" pageId="3" pageNumber="54" reason="2">
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<taxonomicName id="4C5E4D7C4F28FFB7FC9BFD5864EBCF81" authority="Merriam, 1910" authorityName="Merriam" authorityYear="1910" box="[808,1242,642,671]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ichthyosauria" pageId="3" pageNumber="54" phylum="Chordata" rank="species" species="fraasi">
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<emphasis id="B92AEAED4F28FFB7FC9BFD586422CF80" box="[808,1043,642,671]" italics="true" pageId="3" pageNumber="54">Phalarodon fraasi</emphasis>
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<bibRefCitation id="EFCF4B0E4F28FFB7FBA9FD5864EBCF81" author="Merriam, J. C." box="[1050,1242,642,671]" pageId="3" pageNumber="54" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam, 1910</bibRefCitation>
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</taxonomicName>
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</heading>
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</paragraph>
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</subSubSection>
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<subSubSection id="C34465744F28FFB7FC9BFD7463B7CFDD" box="[808,902,686,708]" pageId="3" pageNumber="54" type="description">
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<paragraph id="8BE136FF4F28FFB7FC9BFD7463B7CFDD" blockId="3.[808,902,686,708]" box="[808,902,686,708]" pageId="3" pageNumber="54">
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<figureCitation id="13652A7A4F28FFB7FC9BFD7463B3CFDD" box="[808,898,686,708]" captionStart-0="Fig" captionStart-1="Fig" captionStart-2="Fig" captionStartId-0="2.[151,184,1880,1902]" captionStartId-1="4.[151,184,877,899]" captionStartId-2="5.[98,131,1670,1692]" captionTargetBox-0="[160,1527,172,1854]" captionTargetBox-1="[156,1533,165,851]" captionTargetBox-2="[104,1473,166,1640]" captionTargetId-0="figure-66@2.[154,1532,159,1859]" captionTargetId-1="figure-607@4.[152,1534,162,853]" captionTargetId-2="figure-114@5.[98,1479,162,1644]" captionTargetPageId-0="2" captionTargetPageId-1="4" captionTargetPageId-2="5" captionText-0="Fig. 1. Mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. A. Slab A in concretion, photograph (A1), line drawing (A2) showing the outline and identification of the visible bone elements. B. Hypothetical reconstruction of PMO 235.393." captionText-1="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." captionText-2="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi-0="http://doi.org/10.5281/zenodo.10981079" figureDoi-1="http://doi.org/10.5281/zenodo.10981081" figureDoi-2="http://doi.org/10.5281/zenodo.10981083" httpUri-0="https://zenodo.org/record/10981079/files/figure.png" httpUri-1="https://zenodo.org/record/10981081/files/figure.png" httpUri-2="https://zenodo.org/record/10981083/files/figure.png" pageId="3" pageNumber="54">Figs. 1–3</figureCitation>
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||
.
|
||
</paragraph>
|
||
</subSubSection>
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||
<subSubSection id="C34465744F28FFB7FC9BFD0C63DBCEB1" pageId="3" pageNumber="54" type="diagnosis">
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<paragraph id="8BE136FF4F28FFB7FC9BFD0C63DBCEB1" blockId="3.[808,1481,725,944]" pageId="3" pageNumber="54">
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<emphasis id="B92AEAED4F28FFB7FC9BFD0C63ABCFF1" box="[808,922,726,751]" italics="true" pageId="3" pageNumber="54">Diagnosis</emphasis>
|
||
.—Modified from
|
||
<bibRefCitation id="EFCF4B0E4F28FFB7FBCBFD0F651DCFF1" author="Merriam, J. C." box="[1144,1324,725,751]" pageId="3" pageNumber="54" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam (1910)</bibRefCitation>
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||
and
|
||
<bibRefCitation id="EFCF4B0E4F28FFB7FADDFD0F6343CE0E" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." pageId="3" pageNumber="54" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. (2015)</bibRefCitation>
|
||
. Marginal teeth ankylosed; significant heterodonty between anterior and posterior teeth in the maxilla; dental groove absent anteriorly and posteriorly (not clear in premaxilla of
|
||
<collectionCode id="ED4FAE3A4F28FFB7FC11FC8F63ECCE71" box="[930,989,853,879]" pageId="3" pageNumber="54">PMO</collectionCode>
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||
235.393); number of primary digits in forelimb increased to six; six distal carpals; metatarsal III gives rise to two digits.
|
||
</paragraph>
|
||
</subSubSection>
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||
<subSubSection id="C34465744F28FFB7FC9BFC1A63D1C904" pageId="3" pageNumber="54" type="materials_examined">
|
||
<paragraph id="8BE136FF4F28FFB7FC9BFC1A63D1C904" blockId="3.[808,1481,960,1050]" pageId="3" pageNumber="54">
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<emphasis id="B92AEAED4F28FFB7FC9BFC1A63BBCEC4" box="[808,906,960,986]" italics="true" pageId="3" pageNumber="54">Material</emphasis>
|
||
.—
|
||
<collectionCode id="ED4FAE3A4F28FFB7FC18FC1A63DBCEC4" box="[939,1002,960,986]" pageId="3" pageNumber="54">PMO</collectionCode>
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||
235.393, skull, mandible and some axial and appendicular elements, the Isfjorden area (Spitsbergen), Middle Triassic.
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection id="C34465744F28FFB3FC9BFBF66586CEE0" lastPageId="7" lastPageNumber="58" pageId="3" pageNumber="54" type="description">
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||
<paragraph id="8BE136FF4F28FFB7FC9BFBF66451CB39" blockId="3.[808,1482,1067,1960]" pageId="3" pageNumber="54">
|
||
<emphasis id="B92AEAED4F28FFB7FC9BFBF6639FC95B" box="[808,942,1068,1093]" italics="true" pageId="3" pageNumber="54">Description</emphasis>
|
||
.—The skull, mandible and some axial and appendicular elements are present. Using CT, it is possible to see that the skull is slightly distorted, with the right side positioned lower than the left side (
|
||
<figureCitation id="13652A7A4F28FFB7FB6BFB516510C9BB" box="[1240,1313,1163,1189]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="3" pageNumber="54">Fig. 2</figureCitation>
|
||
). Ontogeny is not possible to determine as no bone surface is preserved. However, based on the size of the specimen and the relative size of the orbit, it is thought to be osteologically mature (
|
||
<bibRefCitation id="EFCF4B0E4F28FFB7FC83FAD66415C839" author="Fernandez, M. S. & Archuby, F. & Talevi, M. & Ebner, R." box="[816,1060,1292,1319]" pageId="3" pageNumber="54" pagination="330 - 337" refId="ref8306" refString="Fernandez, M. S., Archuby, F., Talevi, M., and Ebner, R. 2005. Ichthyosaurian eyes: paleobiological information content in the sclerotic ring of Caypullisaurus (Ichthyosauria, Ophthalmosauria). Journal of Vertebrate Paleontology 25: 330 - 337." type="journal article" year="2005">Fernández et al. 2005</bibRefCitation>
|
||
). No braincase or palatal elements are visible for description on the specimen or by using CT.
|
||
<collectionCode id="ED4FAE3A4F28FFB7FA3EFAF665F8C858" box="[1421,1481,1324,1350]" pageId="3" pageNumber="54">PMO</collectionCode>
|
||
235.393 is referred to
|
||
<taxonomicName id="4C5E4D7C4F28FFB7FBAEFA966488C878" authorityName="Baur" authorityYear="1887" box="[1053,1209,1356,1382]" family="Mixosauridae" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="3" pageNumber="54" phylum="Chordata" rank="family">Mixosauridae</taxonomicName>
|
||
based on the long sagittal crest which reaches the nasal; the large anterior terrace of the upper temporal fenestra; and posterior teeth more robust than anterior teeth. The specimen is referred to
|
||
<taxonomicName id="4C5E4D7C4F28FFB7FAF0FA7665F8C8D8" authorityName="Merriam" authorityYear="1910" box="[1347,1481,1452,1478]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="3" pageNumber="54" phylum="Chordata" rank="genus">
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<emphasis id="B92AEAED4F28FFB7FAF0FA7665F8C8D8" box="[1347,1481,1452,1478]" italics="true" pageId="3" pageNumber="54">Phalarodon</emphasis>
|
||
</taxonomicName>
|
||
based on the presence of significant heterodonty a labial mandibular shelf and the lack of a dental groove in the maxillary region (
|
||
<bibRefCitation id="EFCF4B0E4F28FFB7FC70F9D66465CB39" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[963,1108,1548,1575]" pageId="3" pageNumber="54" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
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||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F28FFB0FCFDF9F661C2C9A5" blockId="3.[808,1482,1067,1960]" lastBlockId="4.[151,825,956,1960]" lastPageId="4" lastPageNumber="55" pageId="3" pageNumber="54">
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<emphasis id="B92AEAED4F28FFB7FCFDF9F6643ECB58" box="[846,1039,1580,1606]" italics="true" pageId="3" pageNumber="54">Skull: Premaxilla</emphasis>
|
||
: Part of the premaxilla is damaged and missing on the left side. Using the CT scan, the right can be described in more detail. No over- or underbite is visible; however, the rostral tip is enclosed in matrix on slab D (
|
||
<collectionCode id="ED4FAE3A4F28FFB7FA35F95765F7CBB9" box="[1414,1478,1677,1703]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="3" pageNumber="54" type="Herbarium">SOM</collectionCode>
|
||
: fig. S4). Numerous teeth are set in the element (see dentition). The dentition cannot be clearly defined due to poor contrast, but there is some indication of ankylosed thecodonty (
|
||
<figureCitation id="13652A7A4F28FFB7FC83F8D76343CA39" box="[816,882,1805,1831]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="3" pageNumber="54">Fig. 3</figureCitation>
|
||
). This is likely a resolution and/or preservation issue, as the three-dimensional
|
||
<taxonomicName id="4C5E4D7C4F28FFB7FB89F8F76532CA59" authorityName="Merriam" authorityYear="1910" box="[1082,1283,1837,1863]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="3" pageNumber="54" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F28FFB7FB89F8F76532CA59" box="[1082,1283,1837,1863]" italics="true" pageId="3" pageNumber="54">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
premaxilla (
|
||
<collectionCode id="ED4FAE3A4F28FFB7FA3FF8F765FBCA59" box="[1420,1482,1837,1863]" pageId="3" pageNumber="54">PMO</collectionCode>
|
||
210.122) described by
|
||
<bibRefCitation id="EFCF4B0E4F28FFB7FB92F89564CFCA79" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[1057,1278,1869,1898]" pageId="3" pageNumber="54" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. (2018)</bibRefCitation>
|
||
shows sockets. In
|
||
<collectionCode id="ED4FAE3A4F28FFB7FC9BF8B46352CA96" box="[808,867,1902,1928]" pageId="3" pageNumber="54">PMO</collectionCode>
|
||
210.122, the sockets are separated by alveolar walls and the length of the tooth crowns nearly equals the length of the roots. The slight compression and distortion of the specimen described herein might be enough to destroy the partitions as these are very thin.
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FEDDFC246275C909" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[366,580,1021,1049]" pageId="4" pageNumber="55" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. (2018)</bibRefCitation>
|
||
also observed that the alveolar walls became more robust and better preserved posteriorly. Small sockets are situated adjacent to larger sockets in
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FF06FB8560C1C967" box="[181,240,1119,1145]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
210.122, which may have contained smaller teeth or demonstrate an uneven pattern of tooth replacement. These are not visible in
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FEE6FB7A61A1C9A4" box="[341,400,1184,1210]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.393.
|
||
</paragraph>
|
||
<caption id="DF2166774F2FFFB0FF24FCB763ACCE81" ID-DOI="http://doi.org/10.5281/zenodo.10981081" ID-Zenodo-Dep="10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="4" pageNumber="55" startId="4.[151,184,877,899]" targetBox="[156,1533,165,851]" targetPageId="4" targetType="figure">
|
||
<paragraph id="8BE136FF4F2FFFB0FF24FCB763ACCE81" blockId="4.[151,1535,877,927]" pageId="4" pageNumber="55">
|
||
Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FC63FCB76560CE9C" authority="(Merriam, 1910) PMO" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[976,1361,877,899]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FC63FCB76449CE9C" box="[976,1144,877,898]" italics="true" pageId="4" pageNumber="55">Phalarodon fraasi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FB35FCB76522CE9D" author="Merriam, J. C." box="[1158,1299,877,899]" pageId="4" pageNumber="55" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam, 1910</bibRefCitation>
|
||
) PMO
|
||
</taxonomicName>
|
||
235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph id="8BE136FF4F2FFFB0FF0EFB1A62DECB1F" blockId="4.[151,825,956,1960]" pageId="4" pageNumber="55">
|
||
The presence of supra- or subnarial processes of the premaxilla of
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FEBEFB3B6179C9E5" box="[269,328,1249,1275]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.391, are not visible on the left side due to the preservation of this region. Using the CT scan data of the covered right side (
|
||
<figureCitation id="13652A7A4F2FFFB0FED4FAF86196C822" box="[359,423,1314,1340]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="4" pageNumber="55">Fig. 2</figureCitation>
|
||
), these processes appear absent as in all
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FF0AFA9961A3C843" box="[185,402,1347,1373]" pageId="4" pageNumber="55">
|
||
<emphasis id="B92AEAED4F2FFFB0FF0AFA99610DC843" box="[185,316,1347,1373]" italics="true" pageId="4" pageNumber="55">Phalarodon</emphasis>
|
||
species
|
||
</taxonomicName>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FE2CFA996247C843" author="Schmitz, L. & Sander, P. M. & Storrs, G. W. & Rieppel, O." box="[415,630,1347,1373]" pageId="4" pageNumber="55" pagination="133 - 162" refId="ref10460" refString="Schmitz, L., Sander, P. M., Storrs, G. W., and Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the Middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica A 270 (4 - 6): 133 - 162." type="journal article" year="2004">Schmitz et al. 2004</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FD33FA996305C843" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[640,820,1347,1373]" pageId="4" pageNumber="55" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FF24FAB96108C863" author="Liu, J. & Motani, R. & Jiang, D. - Y. & Hu, S. - X. & Aitchison, J. C. & Rieppel, O. & Benton, M. J. & Zhang, Q. - Y. & Zhou, C. - Y." box="[151,313,1379,1406]" pageId="4" pageNumber="55" pagination="849 - 866" refId="ref9246" refString="Liu, J., Motani, R., Jiang, D. - Y., Hu, S. - X., Aitchison, J. C., Rieppel, O., Benton, M. J., Zhang, Q. - Y., and Zhou, C. - Y. 2013. The first specimen of the Middle Triassic Phalarodon atavus (Ichthyosauria: Mixosauridae) from South China, showing postcranial anatomy and peri-Tethyan distribution. Palaeontology 56: 849 - 866." type="journal article" year="2013">Liu et al. 2013</bibRefCitation>
|
||
). Here, the posterior margin of the premaxilla only forms the anterior margin of the external naris (
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FD4EFA5E6121C8A1" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." pageId="4" pageNumber="55" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
), a feature which is also present in
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FD28FA7F62E7C8A1" box="[667,726,1445,1471]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.391. This feature is also present in
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FE59FA1C6339C8C1" authorityName="Jiang, Schmitz, Hao, and Sun" authorityYear="2006" box="[490,776,1478,1503]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="panxianensis">
|
||
<emphasis id="B92AEAED4F2FFFB0FE59FA1C6339C8C1" box="[490,776,1478,1503]" italics="true" pageId="4" pageNumber="55">Mixosaurus panxianensis</emphasis>
|
||
</taxonomicName>
|
||
and may be a feature of all mixosaurids (
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FD99FA3C62D2CB1F" author="Jiang, D. - Y. & Schmitz, L. & Hao, W. - C. & Sun, Y. - L." box="[554,739,1510,1537]" pageId="4" pageNumber="55" pagination="60 - 69" refId="ref8961" refString="Jiang, D. - Y., Schmitz, L., Hao, W. - C., and Sun, Y. - L. 2006. A new mixosaurid ichthyosaur from the Middle Triassic of China. Journal of Vertebrate Paleontology 26: 60 - 69." type="journal article" year="2006">Jiang et al. 2006</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2FFFB0FF0EF9DC620DCAB9" blockId="4.[151,825,956,1960]" pageId="4" pageNumber="55">
|
||
Similar to the
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FEE8F9DC627ACB3E" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[347,587,1542,1568]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" isUncertain="true" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FEE8F9DC61D0CB3E" box="[347,481,1542,1568]" italics="true" pageId="4" pageNumber="55">Phalarodon</emphasis>
|
||
cf.
|
||
<emphasis id="B92AEAED4F2FFFB0FDBBF9DC627ACB3E" box="[520,587,1542,1568]" italics="true" pageId="4" pageNumber="55">fraasi</emphasis>
|
||
</taxonomicName>
|
||
specimen (
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FD7AF9DC6309CB3E" box="[713,824,1542,1568]" pageId="4" pageNumber="55">GMPKU-P-</collectionCode>
|
||
1032) the premaxilla of
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FE0FF9FD61C9CB5F" box="[444,504,1575,1601]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.391 borders the maxilla along a diagonal suture. The suture is visible within a small area, although distorted by teeth and not clear. Using CT data for the right side, the suture is shorter than maxilla-nasal suture, a feature differing from
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FD99F9706084CBFA" authorityName="Jiang, Schmitz, Hao, and Sun" authorityYear="2006" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="panxianensis">
|
||
<emphasis id="B92AEAED4F2FFFB0FD99F9706084CBFA" italics="true" pageId="4" pageNumber="55">Mixosaurus panxianensis</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FF42F91061FACBFA" baseAuthorityName="Quenstedt" baseAuthorityYear="1852" box="[241,459,1738,1764]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="avatus">
|
||
<emphasis id="B92AEAED4F2FFFB0FF42F91061FACBFA" box="[241,459,1738,1764]" italics="true" pageId="4" pageNumber="55">Phalarodon avatus</emphasis>
|
||
</taxonomicName>
|
||
, where the sutures to the nasal and maxilla are near equal in length (
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FDF6F93062E8CA1B" author="Motani, R." box="[581,729,1770,1797]" pageId="4" pageNumber="55" pagination="924 - 935" refId="ref9774" refString="Motani, R. 1999. The skull and taxonomy of Mixosaurus (Ichthyopterygia). Journal of Paleontology 73: 924 - 935." type="journal article" year="1999">Motani 1999</bibRefCitation>
|
||
,
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FD55F93060E0CA38" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." pageId="4" pageNumber="55" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
). In the
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FE85F8D661ABCA3B" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[310,410,1803,1829]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FE85F8D661ABCA3B" box="[310,410,1803,1829]" italics="true" pageId="4" pageNumber="55">P. fraasi</emphasis>
|
||
</taxonomicName>
|
||
specimen
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FDAAF8D16264CA3B" box="[537,597,1803,1829]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
210.122,
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FD75F8D66135CA58" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." pageId="4" pageNumber="55" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. (2018)</bibRefCitation>
|
||
described a three-dimensional premaxilla with anteroposteriorly-oriented coarse surface striations, which might also encompass foramina. This is not possible to see on
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FF09F85460C7CAB6" box="[186,246,1934,1960]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.393 due to preservation.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2FFFB0FC37FC66644CC9E2" blockId="4.[862,1535,956,1960]" pageId="4" pageNumber="55">
|
||
<emphasis id="B92AEAED4F2FFFB0FC37FC6663EACEC8" box="[900,987,956,982]" italics="true" pageId="4" pageNumber="55">Maxilla</emphasis>
|
||
: In lateral view, the maxilla is triangular with a long posterior process. It borders the premaxilla anteromedially, the nasal dorsally, and the lacrimal posteriorly. The anterior process of the maxilla appears short on the specimen, although CT analysis revealed this to be broken. The right side shows that maxilla terminates several centimetres anterior to the external naris and forms the entire ventral border of the external naris as in other specimens of
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FCEDFB1A641CC9C5" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[862,1069,1216,1243]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FCEDFB1A641CC9C5" box="[862,1069,1216,1243]" italics="true" pageId="4" pageNumber="55">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
and also
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FB27FB1B6584C9C4" authorityName="Jiang, Schmitz, Hao, and Sun" authorityYear="2006" box="[1172,1461,1217,1242]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="panxianensis">
|
||
<emphasis id="B92AEAED4F2FFFB0FB27FB1B6584C9C4" box="[1172,1461,1217,1242]" italics="true" pageId="4" pageNumber="55">Mixosaurus panxianensis</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FA71FB1A63E4C9E5" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." pageId="4" pageNumber="55" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FC52FB3B6443C9E2" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[993,1138,1249,1276]" pageId="4" pageNumber="55" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2FFFB0FC37FAD864EACB9D" blockId="4.[862,1535,956,1960]" pageId="4" pageNumber="55">
|
||
The maxilla articulates to the prefrontal posterodorsally, the lacrimal posteriorly, and the jugal posteroventrally. The posteriorly-pointed maxilla (common in mixosaurids, see
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FCEDFAB963C1C860" author="Motani, R." box="[862,1008,1379,1406]" pageId="4" pageNumber="55" pagination="924 - 935" refId="ref9774" refString="Motani, R. 1999. The skull and taxonomy of Mixosaurus (Ichthyopterygia). Journal of Paleontology 73: 924 - 935." type="journal article" year="1999">Motani 1999</bibRefCitation>
|
||
and
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FB9FFAB964DDC860" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[1068,1260,1379,1406]" pageId="4" pageNumber="55" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
) is often overlapped by the jugal just anteriorly to the orbital margin, as in other specimens of
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FC4EFA7F64E1C8A1" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[1021,1232,1445,1471]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FC4EFA7F64E1C8A1" box="[1021,1232,1445,1471]" italics="true" pageId="4" pageNumber="55">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
and also
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FAF1FA7F63B5C8C1" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="atavus">
|
||
<emphasis id="B92AEAED4F2FFFB0FAF1FA7F63B5C8C1" italics="true" pageId="4" pageNumber="55">Phalarodon atavus</emphasis>
|
||
</taxonomicName>
|
||
. However, due to distortion in
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FB5CFA1F651AC8C1" box="[1263,1323,1477,1503]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
235.393, the jugal appears to have been pushed anteromedially and is therefore partially disarticulated. Although slightly displaced, the position of this suture differs from that seen in
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FACBF9F263C3CB7F" authorityName="Jiang, Schmitz, Hao, and Sun" authorityYear="2006" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="panxianensis">
|
||
<emphasis id="B92AEAED4F2FFFB0FACBF9F263C3CB7F" italics="true" pageId="4" pageNumber="55">Mixosaurus panxianensis</emphasis>
|
||
</taxonomicName>
|
||
, where it is located just posterior to the anterior orbital margin (
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FB8DF9B264E1CB9D" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[1086,1232,1640,1667]" pageId="4" pageNumber="55" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2FFFB2FC37F95362F4CC27" blockId="4.[862,1535,956,1960]" lastBlockId="6.[151,825,158,1960]" lastPageId="6" lastPageNumber="57" pageId="4" pageNumber="55">
|
||
From the CT scan, there are clear alveoli present in the maxilla. At least seven teeth are present in a single row on the better-preserved right maxilla. Replacement teeth are visible lingually. This confirms the observation in the
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FCEDF8D1641FCA3B" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[862,1070,1803,1829]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FCEDF8D1641FCA3B" box="[862,1070,1803,1829]" italics="true" pageId="4" pageNumber="55">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
specimen from
|
||
<collectingCountry id="F349766F4F2FFFB0FB5AF8D1657DCA3B" box="[1257,1356,1803,1829]" name="Svalbard and Jan Mayen" pageId="4" pageNumber="55">Svalbard</collectingCountry>
|
||
(
|
||
<collectionCode id="ED4FAE3A4F2FFFB0FAEFF8D165ABCA3B" box="[1372,1434,1803,1829]" pageId="4" pageNumber="55">PMO</collectionCode>
|
||
210.122,
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FCEDF8F7640BCA58" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[862,1082,1836,1864]" pageId="4" pageNumber="55" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. 2018</bibRefCitation>
|
||
) of a single row of teeth in the maxilla as in the
|
||
<typeStatus id="54E5885D4F2FFFB0FC4FF897641FCA79" box="[1020,1070,1869,1895]" pageId="4" pageNumber="55">type</typeStatus>
|
||
specimen UCMP 9853 (
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FAFCF89665C2CA79" author="Motani, R." box="[1359,1523,1868,1895]" pageId="4" pageNumber="55" pagination="462 - 465" refId="ref9799" refString="Motani, R. 2005 a. Detailed tooth morphology in a durophagous ichthyosaur captured by 3 D laser scanner. Journal of Vertebrate Paleontology 25 (2): 462 - 465." type="journal article" year="2005">Motani 2005a</bibRefCitation>
|
||
). Resultingly, we removed this character from the species diagnosis for
|
||
<taxonomicName id="4C5E4D7C4F2FFFB0FC6DF854651DCAB6" authority="(Schmitz et al. 2004)" baseAuthorityName="Schmitz" baseAuthorityYear="2004" box="[990,1324,1934,1960]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="4" pageNumber="55" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2FFFB0FC6DF854640CCAB6" box="[990,1085,1934,1960]" italics="true" pageId="4" pageNumber="55">P. fraasi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2FFFB0FBF9F8546514CAB6" author="Schmitz, L. & Sander, P. M. & Storrs, G. W. & Rieppel, O." box="[1098,1317,1934,1960]" pageId="4" pageNumber="55" pagination="133 - 162" refId="ref10460" refString="Schmitz, L., Sander, P. M., Storrs, G. W., and Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the Middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica A 270 (4 - 6): 133 - 162." type="journal article" year="2004">Schmitz et al. 2004</bibRefCitation>
|
||
)
|
||
</taxonomicName>
|
||
. The posterior part of the maxilla bears significantly more robust and bulbous teeth compared to those in the premaxilla and the anterior part of the maxilla (see dentition). This is a dividing feature between
|
||
<taxonomicName id="4C5E4D7C4F2EFFB1FF7BF8B4617CCA99" authorityName="Baur" authorityYear="1887" box="[200,333,1902,1927]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="5" pageNumber="56" phylum="Chordata" rank="genus">
|
||
<emphasis id="B92AEAED4F2EFFB1FF7BF8B4617CCA99" box="[200,333,1902,1927]" italics="true" pageId="5" pageNumber="56">Mixosaurus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName id="4C5E4D7C4F2EFFB1FE34F8B7623DCA99" authorityName="Merriam" authorityYear="1910" box="[391,524,1901,1927]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="5" pageNumber="56" phylum="Chordata" rank="genus">
|
||
<emphasis id="B92AEAED4F2EFFB1FE34F8B7623DCA99" box="[391,524,1901,1927]" italics="true" pageId="5" pageNumber="56">Phalarodon</emphasis>
|
||
</taxonomicName>
|
||
, as
|
||
<taxonomicName id="4C5E4D7C4F2EFFB1FD88F8B462F1CA99" authorityName="Baur" authorityYear="1887" box="[571,704,1902,1927]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="5" pageNumber="56" phylum="Chordata" rank="genus">
|
||
<emphasis id="B92AEAED4F2EFFB1FD88F8B462F1CA99" box="[571,704,1902,1927]" italics="true" pageId="5" pageNumber="56">Mixosaurus</emphasis>
|
||
</taxonomicName>
|
||
lacks true heterodont teeth which are entirely set in a dental groove (
|
||
<bibRefCitation id="EFCF4B0E4F2EFFB1FC83F8D163F1CA38" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[816,960,1803,1830]" pageId="5" pageNumber="56" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
; see also discussion in
|
||
<bibRefCitation id="EFCF4B0E4F2EFFB1FB75F8D665A6CA3B" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[1222,1431,1803,1831]" pageId="5" pageNumber="56" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. 2018</bibRefCitation>
|
||
). As such,
|
||
<collectionCode id="ED4FAE3A4F2EFFB1FCDDF8F66398CA58" box="[878,937,1836,1862]" pageId="5" pageNumber="56">PMO</collectionCode>
|
||
235.393 shares these diagnostic features with
|
||
<taxonomicName id="4C5E4D7C4F2EFFB1FC9BF896643ECA78" box="[808,1039,1868,1894]" family="Mixosauridae" genus="Phalarodon" kingdom="Animalia" pageId="5" pageNumber="56" phylum="Chordata" rank="species" species="undetermined">
|
||
<emphasis id="B92AEAED4F2EFFB1FC9BF896639CCA78" box="[808,941,1868,1894]" italics="true" pageId="5" pageNumber="56">Phalarodon</emphasis>
|
||
species.
|
||
</taxonomicName>
|
||
The CT images also revealed the lingual surface of the maxilla (
|
||
<figureCitation id="13652A7A4F2EFFB1FBCFF8B764E5CA99" box="[1148,1236,1901,1927]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="5" pageNumber="56">Fig. 3A</figureCitation>
|
||
<subScript id="17DA34BA4F2EFFB1FB66F8A364EECA94" attach="right" box="[1237,1247,1913,1930]" fontSize="7" pageId="5" pageNumber="56">5</subScript>
|
||
), which has a clear lingual shelf for articulation with the palate, likely the pterygoid. The maxilla is placed labially in respect to the dentary, so occlusion surfaces between the posterior maxillary teeth and posterior dentary teeth appear to be present (
|
||
<figureCitation id="13652A7A4F2DFFB2FD01FF0562C3CDE7" box="[690,754,223,249]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="6" pageNumber="57">Fig. 3</figureCitation>
|
||
). This maxillary position also seems to be present in the
|
||
<typeStatus id="54E5885D4F2DFFB2FD77FEDA62C7CC04" box="[708,758,256,282]" pageId="6" pageNumber="57">type</typeStatus>
|
||
specimen of
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FF40FEC561F0CC27" box="[243,449,287,313]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FF40FEC561F0CC27" box="[243,449,287,313]" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FE7CFEC56243CC27" author="Merriam, J. C." box="[463,626,287,313]" pageId="6" pageNumber="57" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam 1910</bibRefCitation>
|
||
: fig. 2).
|
||
</paragraph>
|
||
<caption id="DF2166774F2EFFB1FFD1F95C6158CBF1" ID-DOI="http://doi.org/10.5281/zenodo.10981083" ID-Zenodo-Dep="10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="5" pageNumber="56" startId="5.[98,131,1670,1692]" targetBox="[104,1473,166,1640]" targetPageId="5" targetType="figure">
|
||
<paragraph id="8BE136FF4F2EFFB1FFD1F95C6158CBF1" blockId="5.[98,1481,1670,1776]" pageId="5" pageNumber="56">
|
||
Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur
|
||
<taxonomicName id="4C5E4D7C4F2EFFB1FBF2F95C65F8CB85" authority="(Merriam, 1910) PMO" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[1089,1481,1670,1692]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="5" pageNumber="56" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2EFFB1FBF2F95C64DACB85" box="[1089,1259,1670,1691]" italics="true" pageId="5" pageNumber="56">Phalarodon fraasi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2EFFB1FB49F95C65B8CB82" author="Merriam, J. C." box="[1274,1417,1670,1692]" pageId="5" pageNumber="56" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam, 1910</bibRefCitation>
|
||
) PMO
|
||
</taxonomicName>
|
||
235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A
|
||
<subScript id="17DA34BA4F2EFFB1FA21F97665ABCBA4" attach="right" box="[1426,1434,1708,1722]" fontSize="6" pageId="5" pageNumber="56">1</subScript>
|
||
) and labial (A
|
||
<subScript id="17DA34BA4F2EFFB1FF01F912608BCBC8" attach="left" box="[178,186,1736,1750]" fontSize="6" pageId="5" pageNumber="56">2</subScript>
|
||
) views, right dentary (A
|
||
<subScript id="17DA34BA4F2EFFB1FE2EF9126194CBC8" attach="left" box="[413,421,1736,1750]" fontSize="6" pageId="5" pageNumber="56">3</subScript>
|
||
) in dorsal view, right maxilla in dorsal (A
|
||
<subScript id="17DA34BA4F2EFFB1FC98F9126302CBC8" attach="right" box="[811,819,1736,1750]" fontSize="6" pageId="5" pageNumber="56">4</subScript>
|
||
) and lateral (A
|
||
<subScript id="17DA34BA4F2EFFB1FC0CF91263F6CBC8" attach="left" box="[959,967,1736,1750]" fontSize="6" pageId="5" pageNumber="56">5</subScript>
|
||
) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm.
|
||
</paragraph>
|
||
</caption>
|
||
<paragraph id="8BE136FF4F2DFFB2FF0EFE9A625BCE41" blockId="6.[151,825,158,1960]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FF0EFE9A60CFCC44" box="[189,254,320,346]" italics="true" pageId="6" pageNumber="57">Nasal</emphasis>
|
||
: The nasal of
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FE03FE9A61DDCC44" box="[432,492,320,346]" pageId="6" pageNumber="57">PMO</collectionCode>
|
||
235.393 appears reduced in mediolateral extent on slab A. This is likely an artefact of the slightly skewed view and preservation, as the right nasal has a larger mediolateral extent seen in CT (
|
||
<figureCitation id="13652A7A4F2DFFB2FD39FE7A62FCCCA5" box="[650,717,416,443]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="6" pageNumber="57">Fig. 2</figureCitation>
|
||
). The nasal has a long anterior process which surpasses the anterior margin of the external naris and maxilla. The nasal forms the dorsal border of the external naris as in
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FDCDFDDB614BCF22" authority="(Liu et al. 2013)" baseAuthorityName="Liu" baseAuthorityYear="2013" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="atavus">
|
||
<emphasis id="B92AEAED4F2DFFB2FDCDFDDB608CCF25" italics="true" pageId="6" pageNumber="57">Phalarodon atavus</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FF7FFDF86143CF22" author="Liu, J. & Motani, R. & Jiang, D. - Y. & Hu, S. - X. & Aitchison, J. C. & Rieppel, O. & Benton, M. J. & Zhang, Q. - Y. & Zhou, C. - Y." box="[204,370,546,572]" pageId="6" pageNumber="57" pagination="849 - 866" refId="ref9246" refString="Liu, J., Motani, R., Jiang, D. - Y., Hu, S. - X., Aitchison, J. C., Rieppel, O., Benton, M. J., Zhang, Q. - Y., and Zhou, C. - Y. 2013. The first specimen of the Middle Triassic Phalarodon atavus (Ichthyosauria: Mixosauridae) from South China, showing postcranial anatomy and peri-Tethyan distribution. Palaeontology 56: 849 - 866." type="journal article" year="2013">Liu et al. 2013</bibRefCitation>
|
||
)
|
||
</taxonomicName>
|
||
. There is an indication of an anteroposteriorly orientated ridge on the CT scans, directly above the external naris. There is no descending process of the nasal. The posterior extent of the nasal is difficult to discern on the specimen or the CT scans, due to calcite crystal growth inside the concretion in that region. However, a contact between the prefrontal and nasal appears present, although its extent is not visible (
|
||
<figureCitation id="13652A7A4F2DFFB2FE31FCDE61F3CE00" box="[386,450,772,798]" captionStart="Fig" captionStartId="2.[151,184,1880,1902]" captionTargetBox="[160,1527,172,1854]" captionTargetId="figure-66@2.[154,1532,159,1859]" captionTargetPageId="2" captionText="Fig. 1. Mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. A. Slab A in concretion, photograph (A1), line drawing (A2) showing the outline and identification of the visible bone elements. B. Hypothetical reconstruction of PMO 235.393." figureDoi="http://doi.org/10.5281/zenodo.10981079" httpUri="https://zenodo.org/record/10981079/files/figure.png" pageId="6" pageNumber="57">Fig. 1</figureCitation>
|
||
). The nasal appears to terminate posterolaterally with a contact to the frontal where it forms the anteriormost part of the sagittal crest.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FF0EFCBE6201CB1A" blockId="6.[151,825,158,1960]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FF0EFCBE6112CE60" box="[189,291,868,894]" italics="true" pageId="6" pageNumber="57">Lacrimal</emphasis>
|
||
: The lacrimal forms the anteroventral part of the orbit.
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FF69FC5F61F9CE81" author="Schmitz, L. & Sander, P. M. & Storrs, G. W. & Rieppel, O." box="[218,456,901,927]" pageId="6" pageNumber="57" pagination="133 - 162" refId="ref10460" refString="Schmitz, L., Sander, P. M., Storrs, G. W., and Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the Middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica A 270 (4 - 6): 133 - 162." type="journal article" year="2004">Schmitz et al. (2004)</bibRefCitation>
|
||
described an antorbital ridge on the lacrimal of
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FEF2FC7F6209CEA1" box="[321,568,933,959]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="callawayi">
|
||
<emphasis id="B92AEAED4F2DFFB2FEF2FC7F6209CEA1" box="[321,568,933,959]" italics="true" pageId="6" pageNumber="57">Phalarodon callawayi</emphasis>
|
||
</taxonomicName>
|
||
. In
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FDD7FC7F6301CEA1" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[612,816,933,959]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FDD7FC7F6301CEA1" box="[612,816,933,959]" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
, this has been described as “prominent, triangular knob” in the
|
||
<typeStatus id="54E5885D4F2DFFB2FF0CFC3C60C0C91E" box="[191,241,998,1024]" pageId="6" pageNumber="57">type</typeStatus>
|
||
specimen (
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FEDCFC3F6279C91E" author="Merriam, J. C." box="[367,584,997,1024]" pageId="6" pageNumber="57" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam 1910: 387</bibRefCitation>
|
||
). This is more-clearly figured in
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FEBEFBDC6187C93F" author="Motani, R." box="[269,438,1030,1057]" pageId="6" pageNumber="57" pagination="462 - 465" refId="ref9799" refString="Motani, R. 2005 a. Detailed tooth morphology in a durophagous ichthyosaur captured by 3 D laser scanner. Journal of Vertebrate Paleontology 25 (2): 462 - 465." type="journal article" year="2005">Motani (2005a</bibRefCitation>
|
||
: fig. 2). No clear antorbital ridge is visible on
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FEBEFBFC6179C95E" box="[269,328,1062,1088]" pageId="6" pageNumber="57">PMO</collectionCode>
|
||
235.393 due to matrix covering the surface in slab D (see SOM: fig. S4). However, in lateral view, a slight eminence is raised where the prefrontal overlaps with the lacrimal, indicating an antorbital ridge may be present. Similar to
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FEA0FB7D61DAC9DF" box="[275,491,1191,1217]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="atavus">
|
||
<emphasis id="B92AEAED4F2DFFB2FEA0FB7D61DAC9DF" box="[275,491,1191,1217]" italics="true" pageId="6" pageNumber="57">Phalarodon atavus</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FE4FFB7D6269C9DF" box="[508,600,1191,1217]" pageId="6" pageNumber="57">CCCGS</collectionCode>
|
||
LPV 30872,
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FD47FB7D60C0C9FC" author="Liu, J. & Motani, R. & Jiang, D. - Y. & Hu, S. - X. & Aitchison, J. C. & Rieppel, O. & Benton, M. J. & Zhang, Q. - Y. & Zhou, C. - Y." pageId="6" pageNumber="57" pagination="849 - 866" refId="ref9246" refString="Liu, J., Motani, R., Jiang, D. - Y., Hu, S. - X., Aitchison, J. C., Rieppel, O., Benton, M. J., Zhang, Q. - Y., and Zhou, C. - Y. 2013. The first specimen of the Middle Triassic Phalarodon atavus (Ichthyosauria: Mixosauridae) from South China, showing postcranial anatomy and peri-Tethyan distribution. Palaeontology 56: 849 - 866." type="journal article" year="2013">Liu et al. 2013</bibRefCitation>
|
||
), a small and narrow posteroventral process is overlapped by the jugal in lateral view. The anterior part of the orbit is not possible to describe in detail and the border between the prefrontal and the lacrimal is indiscernible. Based on observations from
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FE21FA9361FCC87D" box="[402,461,1353,1379]" pageId="6" pageNumber="57">PMO</collectionCode>
|
||
235.393 and descriptions of the
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FF24FAB36156C89D" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[151,359,1385,1411]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FF24FAB36156C89D" box="[151,359,1385,1411]" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
<typeStatus id="54E5885D4F2DFFB2FEDCFAB06190C89A" box="[367,417,1386,1412]" pageId="6" pageNumber="57">type</typeStatus>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FE02FAB36267C89D" author="Merriam, J. C." box="[433,598,1385,1411]" pageId="6" pageNumber="57" pagination="381 - 390" refId="ref9625" refString="Merriam, J. C. 1910. The skull and dentition of a primitive ichthyosaurian from the Middle Triassic. University of California Publications, Bulletin of the Department of Geology 5: 381 - 390." type="journal article" year="1910">Merriam 1910</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FDD0FAB36332C89A" author="Motani, R." box="[611,771,1385,1412]" pageId="6" pageNumber="57" pagination="462 - 465" refId="ref9799" refString="Motani, R. 2005 a. Detailed tooth morphology in a durophagous ichthyosaur captured by 3 D laser scanner. Journal of Vertebrate Paleontology 25 (2): 462 - 465." type="journal article" year="2005">Motani 2005a</bibRefCitation>
|
||
), we consider it unlikely that the lacrimal is as small as shown in
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FF24FA736158C8DA" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[151,361,1449,1476]" pageId="6" pageNumber="57" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. (2007)</bibRefCitation>
|
||
for
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FE2EFA73625FC8DA" authorityName="PMO" baseAuthorityName="Merriam" baseAuthorityYear="1910" box="[413,622,1449,1476]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FE2EFA73625FC8DA" box="[413,622,1449,1476]" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
GMPKU-P-1032. The element presented there as the prefrontal is more likely to be largely formed by the lacrimal.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FF0EF9D06308CA18" blockId="6.[151,825,158,1960]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FF0EF9D060CBCB3A" box="[189,250,1546,1572]" italics="true" pageId="6" pageNumber="57">Jugal</emphasis>
|
||
: Visible on the CT segmentation (
|
||
<figureCitation id="13652A7A4F2DFFB2FD38F9D062E1CB3B" box="[651,720,1546,1573]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="6" pageNumber="57">Fig. 2</figureCitation>
|
||
), the left jugal is slightly displaced and moved further anteriorly than in life. This would have likely fanned out and covered part of the maxilla and lacrimal as is visible on the well-segmented right side (
|
||
<figureCitation id="13652A7A4F2DFFB2FEC2F9516186CBB8" box="[369,439,1675,1702]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="6" pageNumber="57">Fig. 2</figureCitation>
|
||
). The left jugal is partly exposed on the left side in lateral view on slab A, with part of the posterior ramus preserved on counter slab C (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FD26F91662E7CBF8" box="[661,726,1740,1766]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S3). It forms at least one third of the posterior margin of the orbit.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FF0EF8D7647DCDE4" blockId="6.[151,825,158,1960]" lastBlockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FF0EF8D76103CA39" box="[189,306,1805,1831]" italics="true" pageId="6" pageNumber="57">Prefrontal</emphasis>
|
||
: The prefrontal forms the anterodorsal part of the orbit. A supraorbital crest is present on the prefrontal, although it is uncertain how far posteriorly this crest stretches due to preservation. This is feature is present in many mixosaurids and is clear on
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FE2CF8556406CDA7" authority="(Maisch and Matzke 2000)" baseAuthorityName="Maisch and Matzke" baseAuthorityYear="2000" box="[415,1079,159,1960]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="kuhnschnyderi">
|
||
<emphasis id="B92AEAED4F2DFFB2FE2CF85562E2CAB6" box="[415,723,1934,1960]" italics="true" pageId="6" pageNumber="57">Mixosaurus kuhnschnyderi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FD50F854641ECDA7" author="Maisch, M. W. & Matzke, A. T." box="[739,1071,159,1960]" pageId="6" pageNumber="57" pagination="1 - 159" refId="ref9523" refString="Maisch, M. W. and Matzke, A. T. 2000. The Ichthyosauria. Stuttgarter Beitrage zur Naturkunde, Serie B 298: 1 - 159." type="journal article" year="2000">Maisch and Matzke 2000</bibRefCitation>
|
||
)
|
||
</taxonomicName>
|
||
,
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FBF4FF7A6550CDA7" baseAuthorityName="Motani" baseAuthorityYear="1999" box="[1095,1377,159,185]" family="Mixosauridae" genus="Mixosaurus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="cornalianus">
|
||
<emphasis id="B92AEAED4F2DFFB2FBF4FF7A6550CDA7" box="[1095,1377,159,185]" italics="true" pageId="6" pageNumber="57">Mixosaurus cornalianus</emphasis>
|
||
</taxonomicName>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FAC6FF4563C9CDC7" author="Maisch, M. W. & Matzke, A. T." pageId="6" pageNumber="57" pagination="717 - 732" refId="ref9417" refString="Maisch, M. W. and Matzke, A. T. 1997. Observations on Triassic ichthyosaurs. Part I. Structure of the palate and mode of tooth implantation in Mixosaurus cornalianus (Bassani, 1886). Neues Jahrbuch fur Geologie und Palaontologie Monatshefte 1997 (12): 717 - 732." type="journal article" year="1997">Maisch and Matzke 1997</bibRefCitation>
|
||
,
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FBBAFF656471CDC7" author="Maisch, M. W. & Matzke, A. T." box="[1033,1088,191,217]" pageId="6" pageNumber="57" pagination="105 - 134" refId="ref9474" refString="Maisch, M. W. and Matzke, A. T. 1998. Observations on Triassic ichthyosaurs. Part III: A crested predatory mixosaurid from the Middle Triassic of the Germanic Basin. Neues Jahrbuch fur Geologie und Palaontologie Abhandlungen 209: 105 - 134." type="journal article" year="1998">1998</bibRefCitation>
|
||
)
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FBE6FF656505CDC7" box="[1109,1332,191,217]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="atavus">
|
||
<emphasis id="B92AEAED4F2DFFB2FBE6FF656505CDC7" box="[1109,1332,191,217]" italics="true" pageId="6" pageNumber="57">Phalarodon atavus</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FAC4FF656478CDE4" authority="(Ji et al. 2015)" baseAuthorityName="Ji" baseAuthorityYear="2015" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FAC4FF656390CDE7" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FC1CFF056470CDE4" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[943,1089,223,250]" pageId="6" pageNumber="57" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
)
|
||
</taxonomicName>
|
||
.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FF2563DDCF03" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FF2564A6CC07" box="[900,1175,255,281]" italics="true" pageId="6" pageNumber="57">Orbit and sclerotic ring</emphasis>
|
||
: The orbital margin is circular anteriorly and more irregular posteriorly. This differs from the more irregular orbits seen in some other Triassic ichthyosaurs (
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FC1BFEBA6493CC65" author="Fernandez, M. S. & Archuby, F. & Talevi, M. & Ebner, R." box="[936,1186,352,379]" pageId="6" pageNumber="57" pagination="330 - 337" refId="ref8306" refString="Fernandez, M. S., Archuby, F., Talevi, M., and Ebner, R. 2005. Ichthyosaurian eyes: paleobiological information content in the sclerotic ring of Caypullisaurus (Ichthyosauria, Ophthalmosauria). Journal of Vertebrate Paleontology 25: 330 - 337." type="journal article" year="2005">Fernández et al. 2005</bibRefCitation>
|
||
). The sclerotic ring is partially preserved on the left side, there are at least five elements forming the anterodorsal part of the ring. In cross-section, these curve inwards towards the socket and would have followed the shape of the eye itself, as described in
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FA3AFE3B63D9CF03" author="Fernandez, M. S. & Archuby, F. & Talevi, M. & Ebner, R." pageId="6" pageNumber="57" pagination="330 - 337" refId="ref8306" refString="Fernandez, M. S., Archuby, F., Talevi, M., and Ebner, R. 2005. Ichthyosaurian eyes: paleobiological information content in the sclerotic ring of Caypullisaurus (Ichthyosauria, Ophthalmosauria). Journal of Vertebrate Paleontology 25: 330 - 337." type="journal article" year="2005">Fernández et al. (2005)</bibRefCitation>
|
||
.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FDF8658ACFC3" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FDF863E8CF22" box="[900,985,546,572]" italics="true" pageId="6" pageNumber="57">Frontal</emphasis>
|
||
: Most of the frontal is covered and not visible on the specimen or in the CT images. Only part of the left frontal is preserved on slab B (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FB3CFDB964E1CF63" box="[1167,1232,611,637]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S1) and as an impression on slab A in dorsal view. This preserved portion of the frontal is slightly concave and meets the prefrontal laterally. No part of the frontal-forming sagittal crest is visible.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FD3E64FCCE81" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FD3E6433CFE0" box="[900,1026,740,766]" italics="true" pageId="6" pageNumber="57">Postfrontal</emphasis>
|
||
: The postfrontal is only preserved as an impression on slab A, but is well preserved in dorsal view on slab C (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FC00FCFF63C5CE21" box="[947,1012,805,831]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S2). In dorsal view, the postfrontal has an interdigitating suture with the prefrontal anteriorly (anterior third of orbit). Posteriorly, the postfrontal meets the anterodorsal process of the postorbital.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FC7F656DC81D" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FC7F6430CEA1" box="[900,1025,933,959]" italics="true" pageId="6" pageNumber="57">Postorbital</emphasis>
|
||
: Most of the postorbital is visible in medial view on slab C (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FB93FC1C6450CEFE" box="[1056,1121,966,992]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S3). An impression and dorsal section of the element is present on slab A. Dorsally, the postorbital is overlapped by the supratemporal. Due to significant breakage in this area, the nature of this articulation and the extent of the border with the postfrontal is not entirely clear. Using slab C (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FB32FBBD64F3C99F" box="[1153,1218,1127,1153]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S2), there appears to be small overlap of the postfrontal at the anterodorsal part of the postorbital. Ventrally on slab C, a separate bone fragment which is likely a part of the jugal is present, although these do not clearly articulate (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FB0AFB3364CBC81D" box="[1209,1274,1257,1283]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S3).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FAD36488C8FA" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FAD364C6C83D" box="[900,1271,1289,1315]" italics="true" pageId="6" pageNumber="57">Parietal and temporal fenestrae</emphasis>
|
||
: The parietal is partly preserved as an impression on slab A (
|
||
<figureCitation id="13652A7A4F2DFFB2FA81FAF36544C85D" box="[1330,1397,1321,1347]" captionStart="Fig" captionStartId="2.[151,184,1880,1902]" captionTargetBox="[160,1527,172,1854]" captionTargetId="figure-66@2.[154,1532,159,1859]" captionTargetPageId="2" captionText="Fig. 1. Mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. A. Slab A in concretion, photograph (A1), line drawing (A2) showing the outline and identification of the visible bone elements. B. Hypothetical reconstruction of PMO 235.393." figureDoi="http://doi.org/10.5281/zenodo.10981079" httpUri="https://zenodo.org/record/10981079/files/figure.png" pageId="6" pageNumber="57">Fig. 1</figureCitation>
|
||
) and as an element on slab B (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FBF4FA9364B9C87D" box="[1095,1160,1353,1379]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S1). The temporal fenestra is visible on slab B, with parts of the parietal preserved along the margin. It is likely part of the sagittal crest, but the height and crest-forming elements are equivocal due to matrix cover and preservation.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37FA316436CA39" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37FA3163C1CB1B" box="[900,1008,1515,1541]" italics="true" pageId="6" pageNumber="57">Quadrate</emphasis>
|
||
: The quadrate is preserved on part C and exposed in medial view, but partly encased in sediment (
|
||
<collectionCode id="ED4FAE3A4F2DFFB2FA08F9D165CDCB3B" box="[1467,1532,1547,1573]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="6" pageNumber="57" type="Herbarium">SOM</collectionCode>
|
||
: fig. S2). The outline of the element as shown in
|
||
<figureCitation id="13652A7A4F2DFFB2FA2AF9F165EACB5B" box="[1433,1499,1579,1605]" captionStart="Fig" captionStartId="2.[151,184,1880,1902]" captionTargetBox="[160,1527,172,1854]" captionTargetId="figure-66@2.[154,1532,159,1859]" captionTargetPageId="2" captionText="Fig. 1. Mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. A. Slab A in concretion, photograph (A1), line drawing (A2) showing the outline and identification of the visible bone elements. B. Hypothetical reconstruction of PMO 235.393." figureDoi="http://doi.org/10.5281/zenodo.10981079" httpUri="https://zenodo.org/record/10981079/files/figure.png" pageId="6" pageNumber="57">Fig. 1</figureCitation>
|
||
, is an impression from slab C preserved on slab A. The element is rather large, stretching to most of the dorsoventral height of the postorbital region. As in
|
||
<taxonomicName id="4C5E4D7C4F2DFFB2FA99F95665CFCBB8" box="[1322,1534,1676,1702]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="6" pageNumber="57" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2DFFB2FA99F95665CFCBB8" box="[1322,1534,1676,1702]" italics="true" pageId="6" pageNumber="57">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
(GMPKU-P-1032), the quadrate condyle is massive (
|
||
<bibRefCitation id="EFCF4B0E4F2DFFB2FA71F97663EDCBF9" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." pageId="6" pageNumber="57" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
). In lateral view, most of this element would be covered by the postorbital, quadratojugal, squamosal and/or supratemporal.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2DFFB2FC37F8F765CFCAB6" blockId="6.[862,1535,159,1961]" pageId="6" pageNumber="57">
|
||
<emphasis id="B92AEAED4F2DFFB2FC37F8F764B5CA59" box="[900,1156,1837,1863]" italics="true" pageId="6" pageNumber="57">Other cranial elements</emphasis>
|
||
: No parts of the braincase, palate or quadratojugal are visible on the specimen or on the CT scan images due to the poor contrast in the posterior region of the skull. A possible part of the squamosal is marked in
|
||
<figureCitation id="13652A7A4F2DFFB2FA0FF85465C8CAB6" box="[1468,1529,1934,1960]" captionStart="Fig" captionStartId="2.[151,184,1880,1902]" captionTargetBox="[160,1527,172,1854]" captionTargetId="figure-66@2.[154,1532,159,1859]" captionTargetPageId="2" captionText="Fig. 1. Mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. A. Slab A in concretion, photograph (A1), line drawing (A2) showing the outline and identification of the visible bone elements. B. Hypothetical reconstruction of PMO 235.393." figureDoi="http://doi.org/10.5281/zenodo.10981079" httpUri="https://zenodo.org/record/10981079/files/figure.png" pageId="6" pageNumber="57">Fig. 1</figureCitation>
|
||
.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FF44611BCF05" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
<emphasis id="B92AEAED4F2CFFB3FF34FF4460C3CDA6" box="[135,242,158,184]" italics="true" pageId="7" pageNumber="58">Mandible</emphasis>
|
||
: Both lower jaws are preserved, although damaged, as a portion is preserved on counter slab D and E. There is no clear transition between the dentary and angular/surangular. In
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FE9DFF25615BCC07" box="[302,362,255,281]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
210.122, a small horizontal shelf of the dentary (labial mandibular shelf,
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FDA1FEC562E4CC27" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[530,725,287,314]" pageId="7" pageNumber="58" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
) on the labial side offsets the teeth slightly towards the lingual margin (
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FF71FEBB61A4CC64" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[194,405,352,380]" pageId="7" pageNumber="58" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. 2018</bibRefCitation>
|
||
). This is also preserved in
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FD74FEBA6332CC64" box="[711,771,352,378]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
235.393, but is more posteriorly pronounced. This is clearly visible in the segmented image of the maxilla and dentary
|
||
<figureCitation id="13652A7A4F2CFFB3FFD9FE1B609FCCC5" box="[106,174,449,475]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="7" pageNumber="58">Fig. 3</figureCitation>
|
||
). This feature is also observed in other
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FDCFFE1B6094CCE5" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2CFFB3FDCFFE1B6094CCE5" italics="true" pageId="7" pageNumber="58">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
and
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FF6AFE3B61E2CCE5" box="[217,467,481,507]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="callawayi">
|
||
<emphasis id="B92AEAED4F2CFFB3FF6AFE3B61E2CCE5" box="[217,467,481,507]" italics="true" pageId="7" pageNumber="58">Phalarodon callawayi</emphasis>
|
||
</taxonomicName>
|
||
specimens (
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FDEFFE3B62CFCCE2" author="Motani, R." box="[604,766,481,508]" pageId="7" pageNumber="58" pagination="462 - 465" refId="ref9799" refString="Motani, R. 2005 a. Detailed tooth morphology in a durophagous ichthyosaur captured by 3 D laser scanner. Journal of Vertebrate Paleontology 25 (2): 462 - 465." type="journal article" year="2005">Motani 2005a</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FFD1FDDB612FCF05" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[98,286,513,540]" pageId="7" pageNumber="58" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FDF86125C91E" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FF34FDF8616BCF22" box="[135,346,546,572]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2CFFB3FF34FDF8616BCF22" box="[135,346,546,572]" italics="true" pageId="7" pageNumber="58">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
has been described as having a dorsally inflected and posteriorly extending angular which is larger than the surangular (
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FE14FDB86240CF62" author="Jiang, D. - Y. & Schmitz, L. & Motani, R. & Hao, W. - C. & Sun, Y. - L." box="[423,625,610,637]" pageId="7" pageNumber="58" pagination="602 - 605" refId="ref9013" refString="Jiang, D. - Y., Schmitz, L., Motani, R., Hao, W. - C., and Sun, Y. - L. 2007. The mixosaurid ichthyosaur Phalarodon cf. P. fraasi from the Middle Triassic of Guizhou Province, China. Journal of Paleontology 81: 602 - 605." type="journal article" year="2007">Jiang et al. 2007</bibRefCitation>
|
||
). The variation within
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FF5AFD586141CF82" authorityName="Merriam" authorityYear="1910" box="[233,368,642,668]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="genus">
|
||
<emphasis id="B92AEAED4F2CFFB3FF5AFD586141CF82" box="[233,368,642,668]" italics="true" pageId="7" pageNumber="58">Phalarodon</emphasis>
|
||
</taxonomicName>
|
||
is not known. The suture between the angular and surangular has not been described for
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FFD1FD196266CFC3" authority="(Schmitz et al. 2004)" baseAuthorityName="Schmitz" baseAuthorityYear="2004" box="[98,599,707,734]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="callawayi">
|
||
<emphasis id="B92AEAED4F2CFFB3FFD1FD19616ECFC3" box="[98,351,707,733]" italics="true" pageId="7" pageNumber="58">Phalarodon callawayi</emphasis>
|
||
(
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FEDDFD19627ECFC3" author="Schmitz, L. & Sander, P. M. & Storrs, G. W. & Rieppel, O." box="[366,591,707,734]" pageId="7" pageNumber="58" pagination="133 - 162" refId="ref10460" refString="Schmitz, L., Sander, P. M., Storrs, G. W., and Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the Middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica A 270 (4 - 6): 133 - 162." type="journal article" year="2004">Schmitz et al. 2004</bibRefCitation>
|
||
)
|
||
</taxonomicName>
|
||
. It is not possible in
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FF1AFD3960D4CFE3" box="[169,229,739,765]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
235.393 to determine the exact suture between the angular and surangular. However, the angular seems to have contributed to at least half the posterior portion of the mandible laterally. Part of the posterior section of the mandible including the articular and quadrate joint, is visible on slabs A, C (
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FEF1FC5F61B2CE81" box="[322,387,901,927]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="7" pageNumber="58" type="Herbarium">SOM</collectionCode>
|
||
: fig. S3). The element is skewed, making it appear more extensive than the actual extent. Part of the outline is exposed and shows the curved contact to the quadrate.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FBDC62CCC9DC" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
The dentition of the mandible is heterodont (
|
||
<figureCitation id="13652A7A4F2CFFB3FD3BFBDC62E9C93E" box="[648,728,1030,1056]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="7" pageNumber="58">Figs. 2</figureCitation>
|
||
,
|
||
<figureCitation id="13652A7A4F2CFFB3FD55FBDC62C4C93E" box="[742,757,1030,1056]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="7" pageNumber="58">3</figureCitation>
|
||
). Anteriorly, conical teeth match those in the premaxilla. Posteriorly, the teeth increase in size and become rounded crushing teeth. These are significantly larger than their counterparts in the maxilla. All teeth are preserved in separate alveoli as in
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FE91FB7D616FC9DF" box="[290,350,1191,1217]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
210.122 (
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FE7BFB7D61CDC9DF" box="[456,508,1191,1217]" pageId="7" pageNumber="58">AJR</collectionCode>
|
||
personal observation).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FB1262BEC85C" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
<emphasis id="B92AEAED4F2CFFB3FF34FB1260E7C9FC" box="[135,214,1224,1250]" italics="true" pageId="7" pageNumber="58">Hyoids</emphasis>
|
||
: Two hyoids are preserved in place, between the two lower jaws. These are only an impression on slab A, but are preserved on counter slab E. They are slightly medially convex with a larger anterior than posterior head.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FA906210C8DA" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
<emphasis id="B92AEAED4F2CFFB3FF34FA9060C3C87D" box="[135,242,1354,1379]" italics="true" pageId="7" pageNumber="58">Dentition</emphasis>
|
||
: Although obscured on the specimen itself, teeth from
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FF51FAB3612FC89D" box="[226,286,1385,1411]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
235.393 are clearly visible in the CT scan
|
||
<figureCitation id="13652A7A4F2CFFB3FFD9FA53608AC8BD" box="[106,187,1417,1443]" captionStart="Fig" captionStartId="4.[151,184,877,899]" captionTargetBox="[156,1533,165,851]" captionTargetId="figure-607@4.[152,1534,162,853]" captionTargetPageId="4" captionText="Fig. 2. The segmented model of right lateral side of the skull of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard." figureDoi="http://doi.org/10.5281/zenodo.10981081" httpUri="https://zenodo.org/record/10981081/files/figure.png" pageId="7" pageNumber="58">Figs. 2</figureCitation>
|
||
,
|
||
<figureCitation id="13652A7A4F2CFFB3FF7AFA5360E9C8BD" box="[201,216,1417,1443]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="7" pageNumber="58">3</figureCitation>
|
||
). It is unclear how many teeth would have been present in the premaxilla and mandible.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34FA106175CBF9" blockId="7.[98,771,158,1960]" pageId="7" pageNumber="58">
|
||
The teeth on
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FEAEFA106168C8FA" box="[285,345,1482,1508]" pageId="7" pageNumber="58">PMO</collectionCode>
|
||
235.393 vary from conical to slightly anteroposteriorly elongated in the anterior region of the jaw. In the posterior region, they are strongly anteroposteriorly elongated with oval cross-sections. This differs from
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FFD1F991616BCB7B" box="[98,346,1611,1637]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="callawayi">
|
||
<emphasis id="B92AEAED4F2CFFB3FFD1F991616BCB7B" box="[98,346,1611,1637]" italics="true" pageId="7" pageNumber="58">Phalarodon callawayi</emphasis>
|
||
</taxonomicName>
|
||
, which has circular teeth in cross-section in the anterior part of the jaw, and from
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FDE5F9B160A6CBBB" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="atavus">
|
||
<emphasis id="B92AEAED4F2CFFB3FDE5F9B160A6CBBB" italics="true" pageId="7" pageNumber="58">Phalarodon atavus</emphasis>
|
||
</taxonomicName>
|
||
which has conical tooth crowns with a figure-of-eight cross-section in posterior maxillary teeth (
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FDEFF97660ACCBF8" author="Schmitz, L. & Sander, P. M. & Storrs, G. W. & Rieppel, O." pageId="7" pageNumber="58" pagination="133 - 162" refId="ref10460" refString="Schmitz, L., Sander, P. M., Storrs, G. W., and Rieppel, O. 2004. New Mixosauridae (Ichthyosauria) from the Middle Triassic of the Augusta Mountains (Nevada, USA) and their implications for mixosaur taxonomy. Palaeontographica A 270 (4 - 6): 133 - 162." type="journal article" year="2004">Schmitz et al. 2004</bibRefCitation>
|
||
;
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FF1BF9166108CBF9" author="Ji, C. & Jiang, D. - Y. & Motani, R. & Rieppel, O. & Hao, W. - C. & Sun, Z. - Y." box="[168,313,1740,1767]" pageId="7" pageNumber="58" pagination="1025956" refId="ref8796" refString="Ji, C., Jiang, D. - Y., Motani, R., Rieppel, O., Hao, W. - C., and Sun, Z. - Y. 2015. Phylogeny of the Ichthyopterygia incorporating recent discoveries from South China. Journal of Vertebrate Paleontology 36: e 1025956." type="journal article" year="2015">Ji et al. 2015</bibRefCitation>
|
||
).
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FF34F9366532CCA4" blockId="7.[98,771,158,1960]" lastBlockId="7.[808,1482,159,1024]" pageId="7" pageNumber="58">
|
||
The dentition in the anterior part of the premaxilla and dentary consists of elongated piercing teeth which end in a sharp point (
|
||
<collectionCode id="ED4FAE3A4F2CFFB3FF40F8F76105CA59" box="[243,308,1837,1863]" country="Bulgaria" lsid="urn:lsid:biocol.org:col:12731" name="Bulgarian Academy of Sciences" pageId="7" pageNumber="58" type="Herbarium">SOM</collectionCode>
|
||
: fig. S5). This differs significantly from the flattened and anteroposteriorly elongated crushing teeth in the posterior parts of the maxilla and dentary. The teeth in the posterior end of the dentary are twice the size of the teeth in the maxilla, both in height and anteroposterior length. An anteriorly positioned tooth in the maxilla is
|
||
<quantity id="4CA69B1A4F2CFFB3FA08FF656365CDE4" metricMagnitude="-3" metricUnit="m" metricValue="3.0" pageId="7" pageNumber="58" unit="mm" value="3.0">3 mm</quantity>
|
||
anteroposteriorly long, which indicates a size around
|
||
<quantity id="4CA69B1A4F2CFFB3FA08FF056365CC04" metricMagnitude="-3" metricUnit="m" metricValue="5.0" pageId="7" pageNumber="58" unit="mm" value="5.0">5 mm</quantity>
|
||
in anteroposterior length for the more posterior teeth in the maxilla. Posterior teeth in the maxilla and in the dentary can be studied in CT scans. The posterior teeth in the dentary are approximately twice the size of the posterior teeth in the maxilla, approximately
|
||
<quantity id="4CA69B1A4F2CFFB3FB22FE5A64D9CC85" box="[1169,1256,384,411]" metricMagnitude="-2" metricUnit="m" metricValue="1.0" pageId="7" pageNumber="58" unit="mm" value="10.0">10 mm</quantity>
|
||
. There are at least seven teeth preserved in the right maxilla.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FCFDFE1A647DCFE2" blockId="7.[808,1482,159,1024]" pageId="7" pageNumber="58">
|
||
There is a distinct difference between the tooth attachment in the anterior parts of the premaxilla and the dentary. From CT scans, the teeth are clearly visible in sockets in the dentary (
|
||
<figureCitation id="13652A7A4F2CFFB3FC04FDFB63C8CF25" box="[951,1017,545,571]" captionStart="Fig" captionStartId="5.[98,131,1670,1692]" captionTargetBox="[104,1473,166,1640]" captionTargetId="figure-114@5.[98,1479,162,1644]" captionTargetPageId="5" captionText="Fig. 3. The computed tomography rendered segmentation of rostral elements of mixosaurid ichthyosaur Phalarodon fraasi (Merriam, 1910) PMO 235.393, from the Botneheia Formation, Middle Triassic of the Isfjorden area in Spitsbergen, Svalbard. Right dentary and maxilla in lingual (A1) and labial (A2) views, right dentary (A3) in dorsal view, right maxilla in dorsal (A4) and lateral (A5) views. Note that the dorsal extent of the maxilla is not complete. Scale bars 10 mm." figureDoi="http://doi.org/10.5281/zenodo.10981083" httpUri="https://zenodo.org/record/10981083/files/figure.png" pageId="7" pageNumber="58">Fig. 3</figureCitation>
|
||
). In the premaxilla, these are diffuse and hard to identify. This fits the description for
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FAF0FD9B635BCF62" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2CFFB3FAF0FD9B635BCF62" italics="true" pageId="7" pageNumber="58">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
by
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FC28FDBB6471CF62" author="Motani, R." box="[923,1088,609,636]" pageId="7" pageNumber="58" pagination="81 - 103" refId="ref9726" refString="Motani, R. 1997. Temporal and spatial distribution of tooth implantations in ichthyosaurs. In: J. M. Callaway and E. L. Nicholls (eds.), Ancient Marine Reptiles, 81 - 103. Academic Press, San Diego." type="book chapter" year="1997">Motani (1997)</bibRefCitation>
|
||
as having subthecodont dentition anteriorly only in the upper jaw. In the maxilla, alveoli are clearly visible, and the dentition appears to be anchylosed thecodont as described by
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FBFCFD1864C0CFC2" author="Motani, R." box="[1103,1265,706,732]" pageId="7" pageNumber="58" pagination="81 - 103" refId="ref9726" refString="Motani, R. 1997. Temporal and spatial distribution of tooth implantations in ichthyosaurs. In: J. M. Callaway and E. L. Nicholls (eds.), Ancient Marine Reptiles, 81 - 103. Academic Press, San Diego." type="book chapter" year="1997">Motani (1997)</bibRefCitation>
|
||
. This is not as clear posteriorly in the dentary.
|
||
</paragraph>
|
||
<paragraph id="8BE136FF4F2CFFB3FCFDFCD86586CEE0" blockId="7.[808,1482,159,1024]" pageId="7" pageNumber="58">
|
||
<emphasis id="B92AEAED4F2CFFB3FCFDFCD86471CE02" box="[846,1088,770,796]" italics="true" pageId="7" pageNumber="58">Postcranial material</emphasis>
|
||
: At least six vertebrae are seen on the different slabs, together with disarticulated neural arches. Many of these are better preserved on slab C. Several ribs are partially preserved. In addition, there are some broken appendicular elements, either the scapula or the coracoid. Due to the fragmented nature this is not possible to determine. For a better-preserved pectoral girdle of
|
||
<taxonomicName id="4C5E4D7C4F2CFFB3FC9BFC3E63C9CEE0" box="[808,1016,996,1022]" family="Mixosauridae" genus="Phalarodon" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="7" pageNumber="58" phylum="Chordata" rank="species" species="fraasi">
|
||
<emphasis id="B92AEAED4F2CFFB3FC9BFC3E63C9CEE0" box="[808,1016,996,1022]" italics="true" pageId="7" pageNumber="58">Phalarodon fraasi</emphasis>
|
||
</taxonomicName>
|
||
from
|
||
<collectingCountry id="F349766F4F2CFFB3FB8EFC3E6490CEE0" box="[1085,1185,996,1022]" name="Svalbard and Jan Mayen" pageId="7" pageNumber="58">Svalbard</collectingCountry>
|
||
see
|
||
<bibRefCitation id="EFCF4B0E4F2CFFB3FB61FC3F6582CEE0" author="Okland, I. H. & Delsett, L. L. & Roberts, A. J. & Hurum, J. H." box="[1234,1459,996,1024]" pageId="7" pageNumber="58" pagination="267 - 288" refId="ref10128" refString="Okland, I. H., Delsett, L. L., Roberts, A. J., and Hurum, J. H. 2018. A Phalarodon fraasi (Ichthyosauria: Mixosauridae) from the Middle Triassic of Svalbard. Norwegian Journal of Geology 98: 267 - 288." type="journal article" year="2018">Økland et al. (2018)</bibRefCitation>
|
||
.
|
||
</paragraph>
|
||
</subSubSection>
|
||
<subSubSection id="C34465744F2CFFB3FC9BFBD5656CC957" pageId="7" pageNumber="58" type="distribution">
|
||
<paragraph id="8BE136FF4F2CFFB3FC9BFBD5656CC957" blockId="7.[808,1481,1039,1098]" pageId="7" pageNumber="58">
|
||
<emphasis id="B92AEAED4F2CFFB3FC9BFBD564D3C937" box="[808,1250,1039,1065]" italics="true" pageId="7" pageNumber="58">Stratigraphic and geographic range</emphasis>
|
||
.—Middle Triassic,
|
||
<collectingCountry id="F349766F4F2CFFB3FC9BFBF56341C957" box="[808,880,1071,1097]" name="China" pageId="7" pageNumber="58">China</collectingCountry>
|
||
, Central Europe, North-America,
|
||
<collectingCountry id="F349766F4F2CFFB3FB42FBF56569C957" box="[1265,1368,1071,1097]" name="Svalbard and Jan Mayen" pageId="7" pageNumber="58">Svalbard</collectingCountry>
|
||
.
|
||
</paragraph>
|
||
</subSubSection>
|
||
</treatment>
|
||
</document> |