treatments-xml/data/03/90/87/039087D7C0164634FF68FBA7FB1234EC.xml

<document id="821B5D2EAA83786DD3528F6A2A5BEA95" ID-DOI="10.11646/zootaxa.3927.1.1" ID-GBIF-Dataset="c9f96009-d3d4-4977-9cd5-6004214d1036" ID-ISSN="1175-5326" ID-Zenodo-Dep="288034" ID-ZooBank="42B56D11-9B18-4FCC-B632-30A46AB0205C" IM.materialsCitations_approvedBy="felipe" IM.metadata_approvedBy="felipe" IM.tables_requiresApprovalFor="existingObjects,plazi" IM.taxonomicNames_approvedBy="felipe" checkinTime="1461008886271" checkinUser="plazi" docAuthor="Koppka, Jens" docDate="2015" docId="039087D7C0164634FF68FBA7FB1234EC" docLanguage="en" docName="zt03927p117.pdf" docOrigin="Zootaxa 3927 (1)" docStyle="DocumentStyle:5EBBA59367AD13919D70D935FA04F6A3.14:Zootaxa.2013-.monograph" docStyleId="5EBBA59367AD13919D70D935FA04F6A3" docStyleName="Zootaxa.2013-.monograph" docStyleVersion="14" docTitle="Circunula Koppka, 2015, n. gen." docType="treatment" docUuid="E502D251-D402-446E-A9AB-E60888911559" docUuidSource="ZooBank" docVersion="8" lastPageNumber="21" masterDocId="FFA9FFAFC0194620FFFFFFC3FFF33303" masterDocTitle="Revision of the Bivalvia from the Upper Jurassic Reuchenette Formation, Northwest Switzerland — Ostreoidea" masterLastPageNumber="117" masterPageNumber="1" pageNumber="16" updateTime="1698566318747" updateUser="plazi">
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<mods:title id="6372C0E8A03A40C94042022FB465C9E0">Revision of the Bivalvia from the Upper Jurassic Reuchenette Formation, Northwest Switzerland — Ostreoidea</mods:title>
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<treatment id="039087D7C0164634FF68FBA7FB1234EC" ID-DOI="http://doi.org/10.5281/zenodo.6102690" ID-GBIF-Taxon="127377102" ID-Zenodo-Dep="6102690" LSID="urn:lsid:zoobank.org:act:E502D251-D402-446E-A9AB-E60888911559" httpUri="http://treatment.plazi.org/id/039087D7C0164634FF68FBA7FB1234EC" lastPageId="20" lastPageNumber="21" pageId="15" pageNumber="16">
<subSubSection id="C323654AC0164630FF68FBA7FF0434F6" lastPageId="16" lastPageNumber="17" pageId="15" pageNumber="16" type="nomenclature">
<paragraph id="8B8636C1C016462FFF68FBA7FD38377D" blockId="15.[151,715,1124,1183]" box="[151,715,1124,1150]" pageId="15" pageNumber="16">
<heading id="D0CE81ADC016462FFF68FBA7FD38377D" bold="true" box="[151,715,1124,1150]" fontSize="11" level="1" pageId="15" pageNumber="16" reason="1">
<emphasis id="B94DEAD3C016462FFF68FBA7FD38377D" bold="true" box="[151,715,1124,1150]" pageId="15" pageNumber="16">
<taxonomicName id="4C394D42C016462FFF68FBA7FEE0377D" box="[151,275,1124,1150]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="15" pageNumber="16" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C016462FFF68FBA7FEE0377D" bold="true" box="[151,275,1124,1150]" italics="true" pageId="15" pageNumber="16">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C016462FFEE5FBA7FE9F377D" box="[282,364,1124,1150]" pageId="15" pageNumber="16" rank="genus">n. gen.</taxonomicNameLabel>
<taxonomicName id="4C394D42C016462FFE8BFBA7FD38377D" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[372,715,1124,1150]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFE8BFBA7FE1B377D" bold="true" box="[372,488,1124,1150]" italics="true" pageId="15" pageNumber="16">cotyledon</emphasis>
(
<bibRefCitation id="EFA84B30C016462FFE09FBA7FD30377D" author="Contejean" box="[502,707,1124,1150]" pageId="15" pageNumber="16" refString="Contejean, C. H. (1859) Etude de l'etage Kimmeridien dans les environs de Montbeliard et dans le Jura, la France et l'Angleterre. Memoires de la Societe d'Emulation du Doubs, Year 1858, 1 - 352." type="journal article" year="1859">Contejean, 1859</bibRefCitation>
)
</taxonomicName>
</emphasis>
</heading>
</paragraph>
<paragraph id="8B8636C1C016462FFF68FB45FDBD379C" blockId="15.[151,715,1124,1183]" box="[151,590,1158,1183]" pageId="15" pageNumber="16">
<figureCitation id="13022A44C016462FFF68FB45FEF2379C" box="[151,257,1158,1183]" captionStart-0="FIGURE 5" captionStart-1="FIGURE 6" captionStart-2="FIGURE 7" captionStart-3="FIGURE 8" captionStartId-0="16.[151,250,1484,1506]" captionStartId-1="18.[151,250,1477,1499]" captionStartId-2="18.[151,250,1920,1942]" captionStartId-3="19.[151,250,1805,1827]" captionTargetBox-0="[151,1436,179,1464]" captionTargetBox-1="[211,1368,207,1437]" captionTargetBox-2="[169,1419,1645,1892]" captionTargetBox-3="[160,1427,747,1777]" captionTargetId-0="figure@16.[151,1436,179,1464]" captionTargetId-1="figure@18.[202,1384,195,1456]" captionTargetId-2="figure@18.[163,1424,1641,1898]" captionTargetId-3="figure@19.[151,1435,735,1783]" captionTargetPageId-0="16" captionTargetPageId-1="18" captionTargetPageId-2="18" captionTargetPageId-3="19" captionText-0="FIGURE 5. Circunula n. gen. cotyledon (Contejean, 1859). 1 – 4. Lectotype: 1, idealized drawing of a bivalved specimen, refigured from Contejean (1859, pl. 24, fig. 15), MC 27 E- 105, Rôce in Montbéliard, Lower Kimmeridgian; 2, anteroventral view of LV attached on a Trichites fragment (refigured from Contejean 1859, pl. 24, fig. 16); 3, external view of RV (with attached paralectotype, revealed during preparation); 4, anteroventral view. 5 – 6. Paralectotype, small LV (MC 27 E- 105 a), attached on lectotype: 5, interior view; 6, prosodetic ligament area. 7. Paralectotype, RV interior, with opisthodetic ligament area, MC 27 E- 104, same locality and age as the lectotype. 8 – 9. Paralectotype, MC 27 E- 108, Arbouans near Montbéliard, France, Upper Oxfordian; 8, thick-shelled LV, idealized drawing refigured from Contejean (1859, pl. 24, fig. 17); 9, same LV, interior view. Scale bars 5 mm and 10 mm." captionText-1="FIGURE 6. Circunula n. gen. cotyledon (Contejean, 1859). 1 – 3. Drawings of three juvenile specimens originally attached close together on a Trichites - shell (CGN-ALO 009 - 1, see Fig. 8; Pl. 3.2 – 3), Alombre aux Vaches near Courgenay, Lower Kimmeridgian: 1, LV, umbo prosogyrate, ALO 009 - 1 - II; 2, LV, opisthogyrate, ALO 009 - 1 - I; 3, LV, opisthogyrate, ALO 009 - 1 - III. Scale x 5." captionText-2="FIGURE 7. Circunula n. gen. cotyledon (Contejean, 1859). Ontogeny of ligament area (schematic). 1. LV, juvenile with a triangular, initially alivincular-areate ligament. 2. Recurving of the umbo (hypothetic). 3. Continuation of opisthogyrate twisting, ligament becomes prosodetic and opisthocline, posterior bourrelet overgrown by projection of the posterodorsal hinge margin; observations based on a group of juveniles (ALO 009 - 1 - I-IV, Figs. 6, 8). Scale x 5." captionText-3="FIGURE 8. Circunula n. gen. cotyledon (Contejean, 1859). Group of juvenile LVs attached interior, of a bivalved Trichites (CGN-ALO 009 - 1, largest oyster specimens labelled from I-IV, see also Fig. 6), close to its ventral margin; Alombre aux Vaches (Canton Jura), Lower Kimmeridgian, Banné Marls. Scale x 1.5." httpUri-0="https://zenodo.org/record/288039/files/figure.png" httpUri-1="https://zenodo.org/record/288040/files/figure.png" httpUri-2="https://zenodo.org/record/288041/files/figure.png" httpUri-3="https://zenodo.org/record/288042/files/figure.png" pageId="15" pageNumber="16">Figs. 5–8</figureCitation>
; Pls. 1–2; Pl. 3.1–5; Pl. 4.1, 4
</paragraph>
<paragraph id="8B8636C1C016462FFF60FB1DFBE33644" blockId="15.[159,1204,1246,2013]" pageId="15" pageNumber="16">
? 1837 
<taxonomicName id="4C394D42C016462FFEBFFB1CFDF337F7" box="[320,512,1246,1268]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="multiformis">
<emphasis id="B94DEAD3C016462FFEBFFB1CFDF337F7" box="[320,512,1246,1268]" italics="true" pageId="15" pageNumber="16">Ostrea multiformis</emphasis>
</taxonomicName>
, nobis. 
<taxonomicName id="4C394D42C016462FFDAFFB1CFC6A37F7" authority="Koch &amp; Dunker" authorityName="Koch &amp; Dunker" box="[592,921,1246,1268]" pageId="15" pageNumber="16" rank="variety" variety="orbicularis">
var. 
<emphasis id="B94DEAD3C016462FFD84FB1DFD1F37F7" box="[635,748,1246,1268]" italics="true" pageId="15" pageNumber="16">orbicularis</emphasis>
Koch &amp; Dunker
</taxonomicName>
: p. 45, pl. 5, fig. 11n (only). v * 1859 
<taxonomicName id="4C394D42C016462FFEBFFACAFD63361D" authority="Ctj. Contejean" authorityName="Ctj. Contejean" box="[320,656,1288,1310]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFACAFE1D361D" box="[320,494,1288,1310]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj. Contejean
</taxonomicName>
: p. 319, pl. 24, fig. 
<date id="FF871001C016462FFCABFACBFEE43644" pageId="15" pageNumber="16" value="1861-05-15" valueMax="1861-05-17" valueMin="1861-05-15">15–17. v 1861</date>
<taxonomicName id="4C394D42C016462FFEBFFAF1FDEE3644" authority="Ctj." authorityName="Ctj." box="[320,541,1329,1351]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFAF1FE1D3644" box="[320,494,1329,1351]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Thurmann &amp; Etallon: p. 45, 53, 55, 56, 61, 66.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BFA99FD2F3673" blockId="15.[159,1204,1246,2013]" box="[228,732,1370,1392]" pageId="15" pageNumber="16">
1862 
<taxonomicName id="4C394D42C016462FFEBFFA98FDED3673" authority="Ctj." authorityName="Ctj." box="[320,542,1370,1392]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFA98FE1D3673" box="[320,494,1370,1392]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
— Etallon: p. 442.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BFA47FC143699" blockId="15.[159,1204,1246,2013]" box="[228,999,1412,1434]" pageId="15" pageNumber="16">
1862 
<taxonomicName id="4C394D42C016462FFEBFFA47FDEE3699" authority="Ctj." authorityName="Ctj." box="[320,541,1412,1434]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFA47FE1D3699" box="[320,494,1412,1434]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Thurmann &amp; Etallon: p. 271, pl. 39, fig. 2.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BFA6EFCFC36C0" blockId="15.[159,1204,1246,2013]" box="[228,783,1453,1475]" pageId="15" pageNumber="16">
1867 
<taxonomicName id="4C394D42C016462FFEBFFA6DFDEE36C0" authority="Ctj." authorityName="Ctj." box="[320,541,1453,1475]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFA6DFE1D36C0" box="[320,494,1453,1475]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Greppin, J.-B.: p. 92.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BFA15FD2F36EF" blockId="15.[159,1204,1246,2013]" box="[228,732,1494,1516]" pageId="15" pageNumber="16">
1867 
<taxonomicName id="4C394D42C016462FFEBFFA14FDED36EF" authority="Ctj." authorityName="Ctj." box="[320,542,1494,1516]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFFA14FE1D36EF" box="[320,494,1494,1516]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Moesch: p. 200.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF9C3FCB23515" blockId="15.[159,1204,1246,2013]" box="[228,833,1536,1558]" pageId="15" pageNumber="16">
1870 
<taxonomicName id="4C394D42C016462FFEBFF9C2FDEE3515" authority="Ctj." authorityName="Ctj." box="[320,541,1536,1558]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF9C2FE1D3515" box="[320,494,1536,1558]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Greppin, J.-B.: p. 82, 104.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF9EAFB86353C" blockId="15.[159,1204,1246,2013]" box="[228,1141,1577,1599]" pageId="15" pageNumber="16">
1872 
<taxonomicName id="4C394D42C016462FFEBFF9E9FE1D353C" box="[320,494,1577,1599]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF9E9FE1D353C" box="[320,494,1577,1599]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
</taxonomicName>
Contejean—de Loriol, Royer &amp; Tombeck: p. 406, pl. 24, fig. 2.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF991FCE4356B" blockId="15.[159,1204,1246,2013]" box="[228,791,1618,1640]" pageId="15" pageNumber="16">
1880 
<taxonomicName id="4C394D42C016462FFEBFF990FDCE356B" authority="Contej." authorityName="Contej." box="[320,573,1618,1640]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF990FE1D356B" box="[320,494,1618,1640]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
Contej.
</taxonomicName>
—Struckmann: p. 62.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF9BFFBC53591" blockId="15.[159,1204,1246,2013]" box="[228,1078,1660,1682]" pageId="15" pageNumber="16">
1882 
<taxonomicName id="4C394D42C016462FFEBFF9BFFD173591" authority="Dunk. et Koch-Alth" authorityName="Dunk. et Koch-Alth" box="[320,740,1660,1682]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="multiformis">
<emphasis id="B94DEAD3C016462FFEBFF9BFFDF33591" box="[320,512,1660,1682]" italics="true" pageId="15" pageNumber="16">Ostrea multiformis</emphasis>
Dunk. et Koch—Alth
</taxonomicName>
: p. 296 (114), pl. 27 (10), fig. 20.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF966FD3F35B8" blockId="15.[159,1204,1246,2013]" box="[228,716,1701,1723]" pageId="15" pageNumber="16">
1890 
<taxonomicName id="4C394D42C016462FFEBFF965FDED35B8" authority="Ctj." authorityName="Ctj." box="[320,542,1701,1723]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF965FE1D35B8" box="[320,494,1701,1723]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
, Ctj.
</taxonomicName>
—Mathey: p. 17.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF90DFCE835E7" blockId="15.[159,1204,1246,2013]" box="[228,795,1742,1764]" pageId="15" pageNumber="16">
1905 
<taxonomicName id="4C394D42C016462FFEBFF90CFD3F35E7" authority="Contejean-Schmidt" authorityName="Contejean-Schmidt" box="[320,716,1742,1764]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF90CFE1D35E7" box="[320,494,1742,1764]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
Contejean—Schmidt
</taxonomicName>
: p. 159.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF93BFD02340D" blockId="15.[159,1204,1246,2013]" box="[228,753,1784,1806]" pageId="15" pageNumber="16">
1917 
<taxonomicName id="4C394D42C016462FFEBFF93AFDCD340D" authority="Contej." authorityName="Contej." box="[320,574,1784,1806]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF93AFE1D340D" box="[320,494,1784,1806]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
Contej.
</taxonomicName>
—Rollier: p. 590.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF8E2FC613434" blockId="15.[159,1204,1246,2013]" box="[228,914,1825,1847]" pageId="15" pageNumber="16">
1963 
<taxonomicName id="4C394D42C016462FFEBFF8E1FDB83434" authority="Contej." authorityName="Contej." box="[320,587,1825,1847]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF8E1FE0E3434" box="[320,509,1825,1847]" italics="true" pageId="15" pageNumber="16">Liostrea cotyledon</emphasis>
Contej.
</taxonomicName>
—Pčelinčev &amp; Lysenko: p. 133.
</paragraph>
<paragraph id="8B8636C1C016462FFF1BF889FD013463" blockId="15.[159,1204,1246,2013]" box="[228,754,1866,1888]" pageId="15" pageNumber="16">
1971 
<taxonomicName id="4C394D42C016462FFEBFF888FE0F3463" box="[320,508,1866,1888]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF888FE0F3463" box="[320,508,1866,1888]" italics="true" pageId="15" pageNumber="16">Liostrea cotyledon</emphasis>
</taxonomicName>
—Pugaczewska: p. 198.
</paragraph>
<paragraph id="8B8636C1C016462FFF60F8B6FD6A34B0" blockId="15.[159,1204,1246,2013]" pageId="15" pageNumber="16">
<date id="FF871001C016462FFF60F8B6FEE43489" box="[159,279,1908,1930]" pageId="15" pageNumber="16" value="1973-05">v 1973</date>
<taxonomicName id="4C394D42C016462FFEBFF8B7FDE43489" authority="Ctj." authorityName="Ctj." box="[320,535,1908,1930]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF8B7FE1D3489" box="[320,494,1908,1930]" italics="true" pageId="15" pageNumber="16">Ostrea cotyledon</emphasis>
Ctj.
</taxonomicName>
—Contini &amp; Hantzpergue: p. 175. 
<date id="FF871001C016462FFF60F85DFEE434B0" box="[159,279,1949,1971]" pageId="15" pageNumber="16" value="2006-05">v 2006</date>
<taxonomicName id="4C394D42C016462FFEBFF85EFE6034B0" box="[320,403,1949,1971]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="15" pageNumber="16" phylum="Mollusca" rank="genus">Liostrea</taxonomicName>
cotyledon—Hicks: p. 36.
</paragraph>
<paragraph id="8B8636C1C016462FFF60F804FC7734DF" blockId="15.[159,1204,1246,2013]" box="[159,900,1990,2013]" pageId="15" pageNumber="16">
<date id="FF871001C016462FFF60F804FEE434DF" box="[159,279,1990,2012]" pageId="15" pageNumber="16" value="2006-05">v 2006</date>
<taxonomicName id="4C394D42C016462FFEBFF80BFD4234DF" authority="Contejean 1859" authorityName="Contejean" authorityYear="1859" box="[320,689,1990,2013]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="15" pageNumber="16" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C016462FFEBFF80BFE0E34DF" box="[320,509,1990,2013]" italics="true" pageId="15" pageNumber="16">Liostrea cotyledon</emphasis>
(
<bibRefCitation id="EFA84B30C016462FFDF6F805FD5934DF" author="Contejean" box="[521,682,1990,2012]" pageId="15" pageNumber="16" refString="Contejean, C. H. (1859) Etude de l'etage Kimmeridien dans les environs de Montbeliard et dans le Jura, la France et l'Angleterre. Memoires de la Societe d'Emulation du Doubs, Year 1858, 1 - 352." type="journal article" year="1859">Contejean 1859</bibRefCitation>
)
</taxonomicName>
—Richardt: p. 9, 18.
</paragraph>
<caption id="DF466649C0094630FF68FA0FFDB835BA" httpUri="https://zenodo.org/record/288039/files/figure.png" pageId="16" pageNumber="17" targetBox="[151,1436,179,1464]" targetPageId="16">
<paragraph id="8B8636C1C0094630FF68FA0FFDB835BA" blockId="16.[151,1436,1484,1721]" pageId="16" pageNumber="17">
<emphasis id="B94DEAD3C0094630FF68FA0FFEE336E1" bold="true" box="[151,272,1484,1506]" pageId="16" pageNumber="17">FIGURE 5</emphasis>
. 
<taxonomicName id="4C394D42C0094630FEE0FA0FFE7736E1" box="[287,388,1484,1506]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="16" pageNumber="17" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C0094630FEE0FA0FFE7736E1" box="[287,388,1484,1506]" italics="true" pageId="16" pageNumber="17">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C0094630FE71FA0FFE2A36E1" box="[398,473,1484,1506]" pageId="16" pageNumber="17" rank="genus">
<emphasis id="B94DEAD3C0094630FE71FA0FFE2A36E1" bold="true" box="[398,473,1484,1506]" pageId="16" pageNumber="17">n. gen.</emphasis>
</taxonomicNameLabel>
<taxonomicName id="4C394D42C0094630FE1DFA0FFCFF36E1" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[482,780,1484,1506]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="16" pageNumber="17" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C0094630FE1DFA0FFDB636E1" box="[482,581,1484,1506]" italics="true" pageId="16" pageNumber="17">cotyledon</emphasis>
(Contejean, 1859)
</taxonomicName>
. 
<emphasis id="B94DEAD3C0094630FCE7FA0FFCCD36E1" bold="true" box="[792,830,1484,1506]" pageId="16" pageNumber="17">1–4</emphasis>
. Lectotype: 1, idealized drawing of a bivalved specimen, refigured from Contejean (1859, pl. 24, fig. 15), MC 27E-105, Rôce in Montbéliard, Lower Kimmeridgian; 
<emphasis id="B94DEAD3C0094630FB04FA28FAFB3502" bold="true" box="[1275,1288,1515,1537]" pageId="16" pageNumber="17">2</emphasis>
, anteroventral view of LV attached on a 
<taxonomicName id="4C394D42C0094630FE56F9CAFDF1351C" box="[425,514,1545,1567]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="16" pageNumber="17" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0094630FE56F9CAFDF1351C" box="[425,514,1545,1567]" italics="true" pageId="16" pageNumber="17">Trichites</emphasis>
</taxonomicName>
fragment (refigured from Contejean 1859, pl. 24, fig. 16); 
<emphasis id="B94DEAD3C0094630FB90F9CAFB8F351C" bold="true" box="[1135,1148,1545,1567]" pageId="16" pageNumber="17">3</emphasis>
, external view of RV (with attached paralectotype, revealed during preparation); 
<emphasis id="B94DEAD3C0094630FD37F9EBFD27353D" bold="true" box="[712,724,1576,1598]" pageId="16" pageNumber="17">4</emphasis>
, anteroventral view. 
<emphasis id="B94DEAD3C0094630FC4AF9EBFC28353D" bold="true" box="[949,987,1576,1598]" pageId="16" pageNumber="17">5–6</emphasis>
. Paralectotype, small LV (MC 27E-105a), attached on lectotype: 
<emphasis id="B94DEAD3C0094630FE7EF984FE7D355E" bold="true" box="[385,398,1607,1629]" pageId="16" pageNumber="17">5</emphasis>
, interior view; 
<emphasis id="B94DEAD3C0094630FDD0F984FDCF355E" bold="true" box="[559,572,1607,1629]" pageId="16" pageNumber="17">6</emphasis>
, prosodetic ligament area. 
<emphasis id="B94DEAD3C0094630FCAAF984FC92355E" bold="true" box="[853,865,1607,1629]" pageId="16" pageNumber="17">7</emphasis>
. Paralectotype, RV interior, with opisthodetic ligament area, MC 27E-104, same locality and age as the lectotype. 
<emphasis id="B94DEAD3C0094630FCF1F9A6FCC73578" bold="true" box="[782,820,1637,1659]" pageId="16" pageNumber="17">8–9</emphasis>
. Paralectotype, MC 27E-108, Arbouans near Montbéliard, France, Upper Oxfordian; 
<emphasis id="B94DEAD3C0094630FE59F947FE413599" bold="true" box="[422,434,1668,1690]" pageId="16" pageNumber="17">8</emphasis>
, thick-shelled LV, idealized drawing refigured from Contejean (1859, pl. 24, fig. 17); 
<emphasis id="B94DEAD3C0094630FADBF947FAC33599" bold="true" box="[1316,1328,1668,1690]" pageId="16" pageNumber="17">9</emphasis>
, same LV, interior view. Scale bars 5 mm and 10 mm.
</paragraph>
</caption>
<paragraph id="8B8636C1C0094630FF68F923FED3348A" blockId="16.[151,1436,1760,2037]" pageId="16" pageNumber="17">
<emphasis id="B94DEAD3C0094630FF68F923FE0035FA" bold="true" box="[151,499,1760,1785]" pageId="16" pageNumber="17">
<typeStatus id="54828863C0094630FF68F923FEFE35FA" box="[151,269,1760,1785]" pageId="16" pageNumber="17" type="lectotype">Lectotype</typeStatus>
(designated herein
</emphasis>
). 
<taxonomicName id="4C394D42C0094630FDF4F922FC7E35FA" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[523,909,1760,1785]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="16" pageNumber="17" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C0094630FDF4F922FD3F35FA" box="[523,716,1760,1785]" italics="true" pageId="16" pageNumber="17">Ostrea cotyledon</emphasis>
<bibRefCitation id="EFA84B30C0094630FD2BF923FC7E35FA" author="Contejean" box="[724,909,1760,1785]" pageId="16" pageNumber="17" refString="Contejean, C. H. (1859) Etude de l'etage Kimmeridien dans les environs de Montbeliard et dans le Jura, la France et l'Angleterre. Memoires de la Societe d'Emulation du Doubs, Year 1858, 1 - 352." type="journal article" year="1859">Contejean, 1859</bibRefCitation>
</taxonomicName>
(pl. 24, figs. 15–16), MC-27-E-105: Bivalved specimen growing on a fragment of 
<taxonomicName id="4C394D42C0094630FDACF8C7FD46341E" box="[595,693,1796,1821]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="16" pageNumber="17" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0094630FDACF8C7FD46341E" box="[595,693,1796,1821]" italics="true" pageId="16" pageNumber="17">Trichites</emphasis>
</taxonomicName>
sp., with attached younger LV (
<typeStatus id="54828863C0094630FBBEF8C7FB2F341E" box="[1089,1244,1796,1821]" pageId="16" pageNumber="17" type="paralectotype">paralectotype</typeStatus>
) MC-27-E-105a (internal features uncovered by present author) (Fig. 5.1–3). Rôce in Sainte-Suzanne, Montbéliard (Département Doubs, Franche-Comté), 
<collectingCountry id="F32E7651C0094630FE49F88EFDF53467" box="[438,518,1869,1892]" name="France" pageId="16" pageNumber="17">France</collectingCountry>
. Coordinates 
<emphasis id="B94DEAD3C0094630FD5EF88EFD483467" box="[673,699,1869,1892]" italics="true" pageId="16" pageNumber="17">ca</emphasis>
. 
<geoCoordinate id="EE0D5006C0094630FD34F88EFC803466" box="[715,883,1869,1893]" direction="north" orientation="latitude" pageId="16" pageNumber="17" precision="1" value="47.505646">47°30'20.33''N</geoCoordinate>
, 
<geoCoordinate id="EE0D5006C0094630FC7FF88FFBE43466" box="[896,1047,1868,1893]" direction="east" orientation="longitude" pageId="16" pageNumber="17" precision="1" value="6.7975">6°47'51.00''E</geoCoordinate>
. The exact position of the locality is unknown.
</paragraph>
<paragraph id="8B8636C1C0094630FF38F856FF0434F6" blockId="16.[151,1436,1760,2037]" pageId="16" pageNumber="17">
Lower Kimmeridgian, 
<emphasis id="B94DEAD3C0094630FE38F857FDC434AE" box="[455,567,1940,1965]" italics="true" pageId="16" pageNumber="17">cymodoce</emphasis>
Zone; “Niveau 6” of 
<bibRefCitation id="EFA84B30C0094630FCD7F857FC1E34AE" author="Contejean" box="[808,1005,1940,1965]" pageId="16" pageNumber="17" refString="Contejean, C. H. (1859) Etude de l'etage Kimmeridien dans les environs de Montbeliard et dans le Jura, la France et l'Angleterre. Memoires de la Societe d'Emulation du Doubs, Year 1858, 1 - 352." type="journal article" year="1859">Contejean (1859)</bibRefCitation>
, &quot;Calcaires et Marnes à Ptérocères” (= &quot;Marnes du Rang&quot; in eastern 
<collectingCountry id="F32E7651C0094630FE21F87AFDDC34D2" box="[478,559,1977,2001]" name="France" pageId="16" pageNumber="17">France</collectingCountry>
), equivalent of the Banné Member of the 
<collectingCountry id="F32E7651C0094630FC03F87BFBCE34D2" box="[1020,1085,1976,2001]" name="Switzerland" pageId="16" pageNumber="17">Swiss</collectingCountry>
Reuchenette Formation, Upper Jurassic.
</paragraph>
</subSubSection>
<subSubSection id="C323654AC0084631FF38FF54FD6032D3" pageId="17" pageNumber="18" type="materials_examined">
<paragraph id="8B8636C1C0084631FF38FF54FB3B321E" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
<emphasis id="B94DEAD3C0084631FF38FF54FEDC33B3" bold="true" box="[199,303,151,176]" pageId="17" pageNumber="18">Material</emphasis>
. 
<typeStatus id="54828863C0084631FEBFFF5BFE4333B3" box="[320,432,152,176]" pageId="17" pageNumber="18" type="lectotype">Lectotype</typeStatus>
(see above, MC 27E-105), 
<typeStatus id="54828863C0084631FD09FF54FC6B33B3" box="[758,920,151,176]" pageId="17" pageNumber="18" type="paralectotype">paralectotypes</typeStatus>
MC 27E-105a and MC 27E-104 (from 
<typeStatus id="54828863C0084631FA93FF5BFA6F33B3" box="[1388,1436,152,176]" pageId="17" pageNumber="18">type</typeStatus>
locality) (Fig. 5.1–5). 
<typeStatus id="54828863C0084631FE69FF7FFDDD33D6" box="[406,558,188,213]" pageId="17" pageNumber="18" type="paralectotype">Paralectotype</typeStatus>
MJ 27E-108 from Arbouans (between Montbéliard and Audincourt), Upper Oxfordian “ 
<taxonomicName id="4C394D42C0084631FEE0FF22FE1F33FB" authority="Limestone" authorityName="Limestone" box="[287,492,223,248]" class="Gastropoda" family="Naticidae" genus="Natica" kingdom="Animalia" order="Littorinimorpha" pageId="17" pageNumber="18" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0084631FEE0FF22FE9933FB" box="[287,362,225,248]" italics="true" pageId="17" pageNumber="18">Natica</emphasis>
Limestone
</taxonomicName>
” (&quot;Calcaires à Natices&quot;, niveau 2 of 
<bibRefCitation id="EFA84B30C0084631FC6AFF1CFBAF33FB" author="Contejean" box="[917,1116,223,248]" pageId="17" pageNumber="18" refString="Contejean, C. H. (1859) Etude de l'etage Kimmeridien dans les environs de Montbeliard et dans le Jura, la France et l'Angleterre. Memoires de la Societe d'Emulation du Doubs, Year 1858, 1 - 352." type="journal article" year="1859">Contejean (1859)</bibRefCitation>
, equivalent of the Vorbourg Member, Lower Vellerat Formation of 
<collectingCountry id="F32E7651C0084631FDB4FEC7FD25321E" box="[587,726,260,285]" name="Switzerland" pageId="17" pageNumber="18">Switzerland</collectingCountry>
); Musée Cuvier in Montbéliard (Fig. 5.7–9).
</paragraph>
<paragraph id="8B8636C1C0084631FF68FEE4FD6032D3" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
Others—Numerous specimens from the Banné Marls (
<emphasis id="B94DEAD3C0084631FCFAFEE4FC863243" box="[773,885,295,320]" italics="true" pageId="17" pageNumber="18">cymodoce</emphasis>
Zone) from Vâ Tche Tchâ (
<collectionCode id="ED28AE04C0084631FB48FEEBFB013243" box="[1207,1266,296,320]" httpUri="http://grbio.org/cool/mm8z-8ppw" name="VTT Biotechnology, Culture Collection" pageId="17" pageNumber="18">VTT</collectionCode>
), Alombre aux Vaches (ALO), Cras d’Hermont (CRA), Chevenez-La Scierie (CHS) in northwestern 
<collectingCountry id="F32E7651C0084631FB79FE8FFAFF3266" box="[1158,1292,332,357]" name="Switzerland" pageId="17" pageNumber="18">Switzerland</collectingCountry>
and several specimens from a hardground at the base of the 
<emphasis id="B94DEAD3C0084631FD29FEACFC93328B" box="[726,864,367,392]" italics="true" pageId="17" pageNumber="18">lallierianum</emphasis>
Subzone (
<emphasis id="B94DEAD3C0084631FC1EFEACFBBA328B" box="[993,1097,367,392]" italics="true" pageId="17" pageNumber="18">mutabilis</emphasis>
Zone) of Sur Combe Ronde (SCR). One specimen from Blauen (Upper Oxfordian) of the Thurmann Collection (S 1469, = A.1.10.5.7; Pl. 3.19) in the 
<collectionCode id="ED28AE04C0084631FF22FE7BFED632D3" box="[221,293,440,464]" pageId="17" pageNumber="18">MJSN</collectionCode>
Porrentruy (Appendix, 
<tableCitation id="C6BB037AC0084631FDCFFE74FD7132D3" box="[560,642,439,464]" captionStart="TABLE 1" captionStartId="13.[125,211,542,564]" captionText="TABLE 1. Main shell features for the eight oyster species from the Swiss Reuchenette Formation. “ Convex-concave ” RV refers to the nomenclature of Malchus (1990) (see also Malchus &amp; Aberhan 1998). Microstructure data refer to the left valve (LV) except for Actinostreon (LV + RV). The outermost simple prismatic (SP) or cross foliated (CF) shell layer are probably eroded in some species. Abbrevations see under “ Methods: Terminology ”." pageId="17" pageNumber="18">Table 1</tableCitation>
).
</paragraph>
</subSubSection>
<subSubSection id="C323654AC0084631FF38FE1FFDD43547" pageId="17" pageNumber="18" type="description">
<paragraph id="8B8636C1C0084631FF38FE1FFF0C31F3" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
<emphasis id="B94DEAD3C0084631FF38FE1FFEA232F6" bold="true" box="[199,337,476,501]" pageId="17" pageNumber="18">Description</emphasis>
. Shape, size—Left valve almost entirely cemented, larger than RV; ventral shell margin may become detached from surface, bending upwards at angles between 90° and 110°; posteroventral margin usually highest (see paleoecology); RV rather flat, ventrally partly concave, commissural shelf bending upwards, emulating free LV margin (Pl. 1.5d, Pl. 4.1, 4). Examined specimens between 
<quantity id="4CC19B24C0084631FC05FD84FB85315C" box="[1018,1142,583,608]" metricMagnitude="-2" metricUnit="m" metricValue="4.3" metricValueMax="7.5" metricValueMin="1.1" pageId="17" pageNumber="18" unit="cm" value="4.3" valueMax="7.5" valueMin="1.1">1.1–7.5 cm</quantity>
high (Appendix, 
<tableCitation id="C6BB037AC0084631FAC5FD84FA783163" box="[1338,1419,583,608]" captionStart="TABLE 1" captionStartId="13.[125,211,542,564]" captionText="TABLE 1. Main shell features for the eight oyster species from the Swiss Reuchenette Formation. “ Convex-concave ” RV refers to the nomenclature of Malchus (1990) (see also Malchus &amp; Aberhan 1998). Microstructure data refer to the left valve (LV) except for Actinostreon (LV + RV). The outermost simple prismatic (SP) or cross foliated (CF) shell layer are probably eroded in some species. Abbrevations see under “ Methods: Terminology ”." pageId="17" pageNumber="18">Table 1</tableCitation>
). Sculpture—Free part of LV with fine, even-spaced commarginal growth steps (Pl. 1.3b, 5c); very thin shells occasionally revealing external sculpture of attached surface consisting of minute, discontinuous, partly bifurcating, antimarginal and concentric furrows, few antimarginal riblets, and pustules (Pl. 2.5a,b,e, 7a,b) (Pl. 3.3b,c,e).
</paragraph>
<paragraph id="8B8636C1C0084631FF38FD3EFCF8305F" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">RV with weak commarginal growth lines and steps, and few antimarginal riblets (only on well preserved shells) (Pl. 2.2b, 4b, 5b, 6), becoming weakly squamous towards ventral margin (Pl. 1.5b); xenomorphic sculpture rare (smooth attachment surfaces preferred) (Pl. 1.5a,b).</paragraph>
<paragraph id="8B8636C1C0084631FF38FCA5FE4D30EA" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">Ligament area—Small, more or less triangular, alivincular-areate (Fig. 6.1–2); some shells with an initial prosogyrate twist (Fig. 6.1; Pl. 3.3b, 4–5), (Fig. 7.1–3; Pl. 3.4); resilifer weakly concave with slightly convex bourrelets in both valves, but less elevated in RV; early growth stages overgrown by projection of posterodorsal hinge margin (Fig. 7.2–3).</paragraph>
<paragraph id="8B8636C1C0084631FF38FC37FBD13774" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">Internal shell characters—Umbonal cavity lacking. Posterior adductor scar (PAM) round, except dorsally, oblate (Pl. 1.1b) to concave (Pl. 2.1); position in adults posterodorsal, close to shell centre. Large specimens occasionally with deep sickle-shaped gill depression between posterior shell margin and adductor scar, reaching from hinge to branchitellum (LV: Fig. 5.9; Pl. 2.1; RV: Fig. 5.7; Pl. 1.1b; Pl. 3.1).</paragraph>
<paragraph id="8B8636C1C0084631FF38FB41FB2F3606" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
Microstructure—RV with thin (
<emphasis id="B94DEAD3C0084631FDD6FB40FDB93799" box="[553,586,1155,1178]" italics="true" pageId="17" pageNumber="18">ca.</emphasis>
170 µm) continuous outer shell layer of reclined prisms; middle-inner shell layers low-angle foliate without chambering. Prisms and sculptures, commonly bioeroded through grazing by regular echinoids (star-shaped trace fossil 
<taxonomicName id="4C394D42C0084631FD89FB0AFBF937E1" authority="Bromley, 1975" authorityName="Bromley" authorityYear="1975" box="[630,1034,1225,1250]" class="Echinoidea" genus="Gnathichnus" higherTaxonomySource="GBIF" kingdom="Animalia" pageId="17" pageNumber="18" phylum="Echinodermata" rank="species" species="pentax">
<emphasis id="B94DEAD3C0084631FD89FB0AFCAB37E2" box="[630,856,1225,1250]" italics="true" pageId="17" pageNumber="18">Gnathichnus pentax</emphasis>
<bibRefCitation id="EFA84B30C0084631FC9FFB0AFBF937E1" author="Bromley" box="[864,1034,1225,1250]" pageId="17" pageNumber="18" refString="Bromley, R. G (1975) Comparative analysis of fossil and Recent echinoid bioerosion. Palaeontology, 18, 725 - 739." type="journal article" year="1975">Bromley, 1975</bibRefCitation>
</taxonomicName>
; Pl. 2.4b). Left valve not examined but apparently lacking chambers or vesicular shell layers (no indications under light microscope).
</paragraph>
<paragraph id="8B8636C1C0084631FF38FACCFDD43547" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
Prodissoconch, juvenile—Prodissoconch and earliest postlarval shell not preserved. “Juveniles” or smallest adults typically with strongly gyrate ligament area, usually opisthogyrate, but prosogyrate in 7 out of 
<specimenCount id="9D3FFD48C0084631FB01FAF7FA6A364F" box="[1278,1433,1331,1356]" pageId="17" pageNumber="18" type="generic">22 specimens</specimenCount>
. Posterior bourrelet may be very narrow (Fig. 6.3). Shape of juvenile PAM often more crescentic to subrectangular than round and slightly closer to hinge than in adult (
<figureCitation id="13022A44C0084631FD08FAB9FCCE3691" box="[759,829,1402,1427]" captionStart="FIGURE 7" captionStartId="18.[151,250,1920,1942]" captionTargetBox="[169,1419,1645,1892]" captionTargetId="figure@18.[163,1424,1641,1898]" captionTargetPageId="18" captionText="FIGURE 7. Circunula n. gen. cotyledon (Contejean, 1859). Ontogeny of ligament area (schematic). 1. LV, juvenile with a triangular, initially alivincular-areate ligament. 2. Recurving of the umbo (hypothetic). 3. Continuation of opisthogyrate twisting, ligament becomes prosodetic and opisthocline, posterior bourrelet overgrown by projection of the posterodorsal hinge margin; observations based on a group of juveniles (ALO 009 - 1 - I-IV, Figs. 6, 8). Scale x 5." httpUri="https://zenodo.org/record/288041/files/figure.png" pageId="17" pageNumber="18">Fig. 7</figureCitation>
; Pl. 3.3b,c, 5). Small linear chomata on both sides of dorsal margin (
<figureCitation id="13022A44C0084631FEBFFA5EFE5F36B5" box="[320,428,1437,1462]" captionStart-0="FIGURE 6" captionStart-1="FIGURE 7" captionStartId-0="18.[151,250,1477,1499]" captionStartId-1="18.[151,250,1920,1942]" captionTargetBox-0="[211,1368,207,1437]" captionTargetBox-1="[169,1419,1645,1892]" captionTargetId-0="figure@18.[202,1384,195,1456]" captionTargetId-1="figure@18.[163,1424,1641,1898]" captionTargetPageId-0="18" captionTargetPageId-1="18" captionText-0="FIGURE 6. Circunula n. gen. cotyledon (Contejean, 1859). 1 – 3. Drawings of three juvenile specimens originally attached close together on a Trichites - shell (CGN-ALO 009 - 1, see Fig. 8; Pl. 3.2 – 3), Alombre aux Vaches near Courgenay, Lower Kimmeridgian: 1, LV, umbo prosogyrate, ALO 009 - 1 - II; 2, LV, opisthogyrate, ALO 009 - 1 - I; 3, LV, opisthogyrate, ALO 009 - 1 - III. Scale x 5." captionText-1="FIGURE 7. Circunula n. gen. cotyledon (Contejean, 1859). Ontogeny of ligament area (schematic). 1. LV, juvenile with a triangular, initially alivincular-areate ligament. 2. Recurving of the umbo (hypothetic). 3. Continuation of opisthogyrate twisting, ligament becomes prosodetic and opisthocline, posterior bourrelet overgrown by projection of the posterodorsal hinge margin; observations based on a group of juveniles (ALO 009 - 1 - I-IV, Figs. 6, 8). Scale x 5." httpUri-0="https://zenodo.org/record/288040/files/figure.png" httpUri-1="https://zenodo.org/record/288041/files/figure.png" pageId="17" pageNumber="18">Figs. 6–7</figureCitation>
; Pl. 3.2–5) down to height of adductor scar; anterior catachomata (LV) as parallel grooves (length 
<quantity id="4CC19B24C0084631FF0CFA01FE6236DA" box="[243,401,1474,1498]" metricMagnitude="-4" metricUnit="m" metricValue="2.3499999999999996" metricValueMax="3.0" metricValueMin="1.7" pageId="17" pageNumber="18" unit="mm" value="0.235" valueMax="0.3" valueMin="0.17">0.17–0.3 mm</quantity>
, width 
<quantity id="4CC19B24C0084631FE10FA01FD6E36D9" box="[495,669,1474,1498]" metricMagnitude="-4" metricUnit="m" metricValue="1.3" metricValueMax="1.7" metricValueMin="0.8999999999999999" pageId="17" pageNumber="18" unit="mm" value="0.13" valueMax="0.17" valueMin="0.09">0.09–0.17 mm</quantity>
), normal to and along commissural shelf. Posterior catachomata present, larger specimens with relict catachomata especially close to hinge but not always well developed. Chomata overgrown and absent in larger shells (Fig. 7.3; Pl. 1.1b, 4b). Most juveniles and small adults smooth internally (
<figureCitation id="13022A44C0084631FEEEF9E8FE923547" box="[273,353,1579,1604]" captionStart="FIGURE 6" captionStartId="18.[151,250,1477,1499]" captionTargetBox="[211,1368,207,1437]" captionTargetId="figure@18.[202,1384,195,1456]" captionTargetPageId="18" captionText="FIGURE 6. Circunula n. gen. cotyledon (Contejean, 1859). 1 – 3. Drawings of three juvenile specimens originally attached close together on a Trichites - shell (CGN-ALO 009 - 1, see Fig. 8; Pl. 3.2 – 3), Alombre aux Vaches near Courgenay, Lower Kimmeridgian: 1, LV, umbo prosogyrate, ALO 009 - 1 - II; 2, LV, opisthogyrate, ALO 009 - 1 - I; 3, LV, opisthogyrate, ALO 009 - 1 - III. Scale x 5." httpUri="https://zenodo.org/record/288040/files/figure.png" pageId="17" pageNumber="18">Figs. 6</figureCitation>
, 
<figureCitation id="13022A44C0084631FE92F9EFFE8E3547" box="[365,381,1580,1604]" captionStart="FIGURE 8" captionStartId="19.[151,250,1805,1827]" captionTargetBox="[160,1427,747,1777]" captionTargetId="figure@19.[151,1435,735,1783]" captionTargetPageId="19" captionText="FIGURE 8. Circunula n. gen. cotyledon (Contejean, 1859). Group of juvenile LVs attached interior, of a bivalved Trichites (CGN-ALO 009 - 1, largest oyster specimens labelled from I-IV, see also Fig. 6), close to its ventral margin; Alombre aux Vaches (Canton Jura), Lower Kimmeridgian, Banné Marls. Scale x 1.5." httpUri="https://zenodo.org/record/288042/files/figure.png" pageId="17" pageNumber="18">8</figureCitation>
; Pl. 3.3a, 4–5).
</paragraph>
</subSubSection>
<subSubSection id="C323654AC0084634FF38F98CFD8033FB" lastPageId="20" lastPageNumber="21" pageId="17" pageNumber="18" type="discussion">
<paragraph id="8B8636C1C0084631FF38F98CFAF335F5" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
<emphasis id="B94DEAD3C0084631FF38F98CFEC7356B" bold="true" box="[199,308,1615,1640]" pageId="17" pageNumber="18">Remarks</emphasis>
. Coiling—Early postlarval prosogyry is relatively common in 
<taxonomicName id="4C394D42C0084631FBF8F98CFB1D356B" box="[1031,1262,1615,1640]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="17" pageNumber="18" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C0084631FBF8F98CFB1D356B" box="[1031,1262,1615,1640]" italics="true" pageId="17" pageNumber="18">Circunula cotyledon</emphasis>
</taxonomicName>
(e.g. VTT001- 3215, VTT001-3238, VTT001-1613); this tendency is perhaps only matched by Jurassic 
<taxonomicName id="4C394D42C0084631FB69F9B1FF2B35AC" authority="Voltz, 1828" authorityName="Voltz" authorityYear="1828" class="Leotiomycetes" family="Pezizellaceae" genus="Catinula" higherTaxonomySource="CoL" kingdom="Fungi" order="Helotiales" pageId="17" pageNumber="18" phylum="Ascomycota" rank="species" species="knorri">
<emphasis id="B94DEAD3C0084631FB69F9B1FABB3588" box="[1174,1352,1650,1675]" italics="true" pageId="17" pageNumber="18">Catinula knorri</emphasis>
(
<bibRefCitation id="EFA84B30C0084631FAA6F9B1FF2335AC" author="Voltz" pageId="17" pageNumber="18" refString="Voltz, P. L. (1828) Ueberblick der Mineralien der beiden Rhein-Departemente. In: Aufschlager, J. F. (Ed.), Das Elsass. Neue historisch-topographische Beschreibung der beiden Rhein-Departemente. Supplement. J. H. Heitz, Strasburg, pp. 1 - 64." type="book chapter" year="1828">Voltz, 1828</bibRefCitation>
)
</taxonomicName>
(Pl. 4.2, 3b). Prosogyry appears to be somewhat more common among specimens settling on the dark (protected?) interior of a bivalved 
<taxonomicName id="4C394D42C0084631FDC9F97AFD6B35D1" box="[566,664,1721,1746]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="17" pageNumber="18" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0084631FDC9F97AFD6B35D1" box="[566,664,1721,1746]" italics="true" pageId="17" pageNumber="18">Trichites</emphasis>
</taxonomicName>
shell (ALO009-1) or on the underside of 
<taxonomicName id="4C394D42C0084631FB61F979FAE935D2" box="[1182,1306,1722,1745]" class="Bivalvia" family="Pteriidae" genus="Isognomon" kingdom="Animalia" order="Pterioida" pageId="17" pageNumber="18" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0084631FB61F979FAE935D2" box="[1182,1306,1722,1745]" italics="true" pageId="17" pageNumber="18">Isognomon</emphasis>
</taxonomicName>
specimens (VTT001-1615, VTT001-3215), but overall observations do not support an environmental influence.
</paragraph>
<paragraph id="8B8636C1C0084631FF68F8C3FBFA3462" blockId="17.[151,1437,151,1889]" pageId="17" pageNumber="18">
Chomata— 
<taxonomicName id="4C394D42C0084631FEE7F8C3FDF2341A" box="[280,513,1792,1817]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="17" pageNumber="18" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C0084631FEE7F8C3FDF2341A" box="[280,513,1792,1817]" italics="true" pageId="17" pageNumber="18">Circunula cotyledon</emphasis>
</taxonomicName>
is the first Jurassic species with chomata that does not belong to 
<taxonomicName id="4C394D42C0084631FAEBF8C3FA6B341A" box="[1300,1432,1792,1817]" class="Bivalvia" family="Gryphaeidae" kingdom="Animalia" order="Ostreoida" pageId="17" pageNumber="18" phylum="Mollusca" rank="subFamily" subFamily="Exogyrinae">Exogyrinae</taxonomicName>
, 
<taxonomicName id="4C394D42C0084631FF68F8E7FEC2343E" box="[151,305,1828,1853]" class="Bivalvia" family="Arctostreidae" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="17" pageNumber="18" phylum="Mollusca" rank="family">Arctostreidae</taxonomicName>
, or to 
<taxonomicName id="4C394D42C0084631FE7FF8E7FDEF343E" box="[384,540,1828,1853]" class="Bivalvia" genus="Pseudeligmus" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="17" pageNumber="18" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C0084631FE7FF8E7FDEF343E" box="[384,540,1828,1853]" italics="true" pageId="17" pageNumber="18">Pseudeligmus</emphasis>
</taxonomicName>
(
<bibRefCitation id="EFA84B30C0084631FDD2F8E7FD27343E" author="Malchus" box="[557,724,1828,1853]" pageId="17" pageNumber="18" refString="Malchus, N. (1990) Revision der Kreide-Austern (Bivalvia: Pteriomorphia) Agyptens (Biostratigraphie, Systematik). Berliner Geowissenschaftliche Abhandlungen, Reihe A, 125, 1 - 231." type="journal article" year="1990">Malchus 1990</bibRefCitation>
, 1998, p. 402, fig. 5). Their restriction to the early postlarval growth phase and later overgrowth and disappearance is not unusual, however.
</paragraph>
<caption id="DF466649C00B4632FF68FA06FEE9353B" httpUri="https://zenodo.org/record/288040/files/figure.png" pageId="18" pageNumber="19" targetBox="[211,1368,207,1437]" targetPageId="18">
<paragraph id="8B8636C1C00B4632FF68FA06FEE9353B" blockId="18.[151,1436,1477,1592]" pageId="18" pageNumber="19">
<emphasis id="B94DEAD3C00B4632FF68FA06FEFC36D8" bold="true" box="[151,271,1477,1499]" pageId="18" pageNumber="19">FIGURE 6</emphasis>
. 
<taxonomicName id="4C394D42C00B4632FEE1FA06FE7736D8" box="[286,388,1477,1499]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="18" pageNumber="19" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00B4632FEE1FA06FE7736D8" box="[286,388,1477,1499]" italics="true" pageId="18" pageNumber="19">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00B4632FE72FA06FE2436D8" box="[397,471,1477,1499]" pageId="18" pageNumber="19" rank="genus">
<emphasis id="B94DEAD3C00B4632FE72FA06FE2436D8" bold="true" box="[397,471,1477,1499]" pageId="18" pageNumber="19">n. gen.</emphasis>
</taxonomicNameLabel>
<taxonomicName id="4C394D42C00B4632FE1FFA06FCFB36D8" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[480,776,1477,1499]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="18" pageNumber="19" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00B4632FE1FFA06FDB136D8" box="[480,578,1477,1499]" italics="true" pageId="18" pageNumber="19">cotyledon</emphasis>
(Contejean, 1859)
</taxonomicName>
. 
<emphasis id="B94DEAD3C00B4632FCEBFA06FCC936D8" bold="true" box="[788,826,1477,1499]" pageId="18" pageNumber="19">1–3</emphasis>
. Drawings of three juvenile specimens originally attached close together on a 
<taxonomicName id="4C394D42C00B4632FE93FA27FE3636F9" box="[364,453,1508,1530]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="18" pageNumber="19" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00B4632FE93FA27FE3636F9" box="[364,453,1508,1530]" italics="true" pageId="18" pageNumber="19">Trichites</emphasis>
</taxonomicName>
-shell (CGN-ALO009-1, see Fig. 8; Pl. 3.2–3), Alombre aux Vaches near Courgenay, Lower Kimmeridgian: 
<emphasis id="B94DEAD3C00B4632FEC6F9C0FEB5351A" bold="true" box="[313,326,1539,1561]" pageId="18" pageNumber="19">1</emphasis>
, LV, umbo prosogyrate, ALO009-1-II; 
<emphasis id="B94DEAD3C00B4632FD23F9C0FD1B351A" bold="true" box="[732,744,1539,1561]" pageId="18" pageNumber="19">2</emphasis>
, LV, opisthogyrate, ALO009-1-I; 
<emphasis id="B94DEAD3C00B4632FBB7F9C0FBA7351A" bold="true" box="[1096,1108,1539,1561]" pageId="18" pageNumber="19">3</emphasis>
, LV, opisthogyrate, ALO009-1- III. Scale x5.
</paragraph>
</caption>
<caption id="DF466649C00B4632FF68F843FBD434F1" httpUri="https://zenodo.org/record/288041/files/figure.png" pageId="18" pageNumber="19" targetBox="[169,1419,1645,1892]" targetPageId="18">
<paragraph id="8B8636C1C00B4632FF68F843FBD434F1" blockId="18.[151,1436,1920,2034]" pageId="18" pageNumber="19">
<emphasis id="B94DEAD3C00B4632FF68F843FEFC3495" bold="true" box="[151,271,1920,1942]" pageId="18" pageNumber="19">FIGURE 7</emphasis>
. 
<taxonomicName id="4C394D42C00B4632FEE1F843FE773495" box="[286,388,1920,1942]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="18" pageNumber="19" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00B4632FEE1F843FE773495" box="[286,388,1920,1942]" italics="true" pageId="18" pageNumber="19">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00B4632FE72F843FE243495" box="[397,471,1920,1942]" pageId="18" pageNumber="19" rank="genus">
<emphasis id="B94DEAD3C00B4632FE72F843FE243495" bold="true" box="[397,471,1920,1942]" pageId="18" pageNumber="19">n. gen.</emphasis>
</taxonomicNameLabel>
<taxonomicName id="4C394D42C00B4632FE20F843FCF73495" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[479,772,1920,1942]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="18" pageNumber="19" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00B4632FE20F843FDB23495" box="[479,577,1920,1942]" italics="true" pageId="18" pageNumber="19">cotyledon</emphasis>
(Contejean, 1859)
</taxonomicName>
. Ontogeny of ligament area (schematic). 
<emphasis id="B94DEAD3C00B4632FB46F843FB363495" bold="true" box="[1209,1221,1920,1942]" pageId="18" pageNumber="19">1</emphasis>
. LV, juvenile with a triangular, initially alivincular-areate ligament. 
<emphasis id="B94DEAD3C00B4632FD72F85CFD6A34B6" bold="true" box="[653,665,1951,1973]" pageId="18" pageNumber="19">2</emphasis>
. Recurving of the umbo (hypothetic). 
<emphasis id="B94DEAD3C00B4632FBBDF85CFBBD34B6" bold="true" box="[1090,1102,1951,1973]" pageId="18" pageNumber="19">3</emphasis>
. Continuation of opisthogyrate twisting, ligament becomes prosodetic and opisthocline, posterior bourrelet overgrown by projection of the posterodorsal hinge margin; observations based on a group of juveniles (ALO009-1-I-IV, Figs. 6, 8). Scale x5.
</paragraph>
</caption>
<paragraph id="8B8636C1C00A4633FF38FF54FC8A3266" blockId="19.[151,1437,151,680]" pageId="19" pageNumber="20">
<emphasis id="B94DEAD3C00A4633FF38FF54FEAC33B3" bold="true" box="[199,351,151,176]" pageId="19" pageNumber="20">Paleoecology</emphasis>
. 
<taxonomicName id="4C394D42C00A4633FE90FF54FE2C33B3" box="[367,479,151,176]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00A4633FE90FF54FE2C33B3" box="[367,479,151,176]" italics="true" pageId="19" pageNumber="20">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00A4633FE16FF54FDC933B3" box="[489,570,151,176]" pageId="19" pageNumber="20" rank="genus">
<emphasis id="B94DEAD3C00A4633FE16FF54FDC933B3" bold="true" box="[489,570,151,176]" pageId="19" pageNumber="20">n. gen.</emphasis>
</taxonomicNameLabel>
<taxonomicName id="4C394D42C00A4633FDBCFF54FD4333B3" box="[579,688,151,176]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="19" pageNumber="20" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00A4633FDBCFF54FD4333B3" box="[579,688,151,176]" italics="true" pageId="19" pageNumber="20">cotyledon</emphasis>
</taxonomicName>
is a typical pioneer settler on limestone hardgrounds such as the basal hardground of the Banné Member, and layers 2000, 3000 of the Sur Combe Ronde section (
<figureCitation id="13022A44C00A4633FB2CFF7FFAE633D7" box="[1235,1301,188,213]" captionStart="FIGURE 4" captionStartId="10.[151,250,1911,1933]" captionTargetBox="[192,1398,198,1883]" captionTargetId="figure@10.[187,1407,193,1889]" captionTargetPageId="10" captionText="FIGURE 4. Litho- and biostratigraphy of the observed parts of the Reuchenette Formation in the Ajoie, with distribution of oysters and characteristic fossils. A. Synthetic section. B. Detailed section of the Banné Member in Vâ Tche Tchâ (VTT), Lower Kimmeridgian. C. Detailed section of the upper part of the Courtedoux Member and “ Lower Virgula Marl ”; based on Tchâfouè (TCH) and Sur Combe Ronde (SCR), Upper Kimmeridgian (note separate bed numeration for VTT and SCR / TCH)." httpUri="https://zenodo.org/record/288038/files/figure.png" pageId="19" pageNumber="20">Fig. 4</figureCitation>
B–C) where they become largest, develop the thickest shells and usually remain entirely attached (Pl. 1.2, Pl. 2.1, 7). They also occur commonly on 
<taxonomicName id="4C394D42C00A4633FE75FEC6FDF5321F" box="[394,518,261,284]" class="Bivalvia" family="Pteriidae" genus="Isognomon" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FE75FEC6FDF5321F" box="[394,518,261,284]" italics="true" pageId="19" pageNumber="20">Isognomon</emphasis>
</taxonomicName>
shells (Pl. 2.3) in oolitic and biomicritic sediments of the basal Banné Marls. Optimal conditions thus appear to have been medium to high energy environments in shallow marine carbonate settings, where most of the other oyster species could not survive.
</paragraph>
<paragraph id="8B8636C1C00A4633FF38FEACFB5432D3" blockId="19.[151,1437,151,680]" pageId="19" pageNumber="20">
Small articulated adults (
<quantity id="4CC19B24C00A4633FE22FEB3FDC1328B" box="[477,562,368,392]" metricMagnitude="-2" metricUnit="m" metricValue="2.5" metricValueMax="3.0" metricValueMin="2.0" pageId="19" pageNumber="20" unit="cm" value="2.5" valueMax="3.0" valueMin="2.0">2–3 cm</quantity>
) with a raised ventral margin are more typical of the highly fossiliferous marls of the middle Banné Member (Pl. 1.3, Pl. 2.4, Pl. 4.1), settling on large, smooth shell surfaces of 
<taxonomicName id="4C394D42C00A4633FAE7FE56FA6732AF" box="[1304,1428,405,428]" class="Bivalvia" family="Pteriidae" genus="Isognomon" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FAE7FE56FA6732AF" box="[1304,1428,405,428]" italics="true" pageId="19" pageNumber="20">Isognomon</emphasis>
</taxonomicName>
, 
<taxonomicName id="4C394D42C00A4633FF68FE7BFEE732CC" box="[151,276,440,463]" class="Bivalvia" family="Ceratomyidae" genus="Ceratomya" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pholadomyoida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FF68FE7BFEE732CC" box="[151,276,440,463]" italics="true" pageId="19" pageNumber="20">Ceratomya</emphasis>
</taxonomicName>
(Pl. 1.5), and 
<taxonomicName id="4C394D42C00A4633FE4CFE74FDE632D3" box="[435,533,439,464]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FE4CFE74FDE632D3" box="[435,533,439,464]" italics="true" pageId="19" pageNumber="20">Trichites</emphasis>
</taxonomicName>
(Pl. 3.5). These deposits likely indicate calmer conditions.
</paragraph>
<paragraph id="8B8636C1C00A4633FF38FE1FFDF631AB" blockId="19.[151,1437,151,680]" pageId="19" pageNumber="20">
<figureCitation id="13022A44C00A4633FF38FE1FFEDB32F7" box="[199,296,476,501]" captionStart="FIGURE 8" captionStartId="19.[151,250,1805,1827]" captionTargetBox="[160,1427,747,1777]" captionTargetId="figure@19.[151,1435,735,1783]" captionTargetPageId="19" captionText="FIGURE 8. Circunula n. gen. cotyledon (Contejean, 1859). Group of juvenile LVs attached interior, of a bivalved Trichites (CGN-ALO 009 - 1, largest oyster specimens labelled from I-IV, see also Fig. 6), close to its ventral margin; Alombre aux Vaches (Canton Jura), Lower Kimmeridgian, Banné Marls. Scale x 1.5." httpUri="https://zenodo.org/record/288042/files/figure.png" pageId="19" pageNumber="20">Figure 8</figureCitation>
and Plate 3.2–3 show a larger slab of a 
<taxonomicName id="4C394D42C00A4633FCF7FE1FFC9932F6" box="[776,874,476,501]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FCF7FE1FFC9932F6" box="[776,874,476,501]" italics="true" pageId="19" pageNumber="20">Trichites</emphasis>
</taxonomicName>
shell (ALO009-1, bivalved specimen) with 
<emphasis id="B94DEAD3C00A4633FA92FE1EFF1F311B" italics="true" pageId="19" pageNumber="20">post mortem</emphasis>
settlement by more than 
<specimenCount id="9D3FFD48C00A4633FDF7FDC3FD75311B" box="[520,646,511,536]" pageId="19" pageNumber="20" type="juvenile">20 juvenile</specimenCount>
specimens. Overall, shells are attached with their ventral side directed towards the ventral margin of the 
<taxonomicName id="4C394D42C00A4633FDF1FDE7FD83313E" box="[526,624,548,573]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FDF1FDE7FD83313E" box="[526,624,548,573]" italics="true" pageId="19" pageNumber="20">Trichites</emphasis>
</taxonomicName>
shell. Specimens are much larger close to the margin than those attached more dorsally (
<figureCitation id="13022A44C00A4633FEBAFD84FE783163" box="[325,395,583,608]" captionStart="FIGURE 8" captionStartId="19.[151,250,1805,1827]" captionTargetBox="[160,1427,747,1777]" captionTargetId="figure@19.[151,1435,735,1783]" captionTargetPageId="19" captionText="FIGURE 8. Circunula n. gen. cotyledon (Contejean, 1859). Group of juvenile LVs attached interior, of a bivalved Trichites (CGN-ALO 009 - 1, largest oyster specimens labelled from I-IV, see also Fig. 6), close to its ventral margin; Alombre aux Vaches (Canton Jura), Lower Kimmeridgian, Banné Marls. Scale x 1.5." httpUri="https://zenodo.org/record/288042/files/figure.png" pageId="19" pageNumber="20">Fig. 8</figureCitation>
). This orientation may indicate preferential growth close to nutrient-rich incoming current. The idea is supported by similarly oriented specimens of 
<taxonomicName id="4C394D42C00A4633FCDEFDAEFBF73187" box="[801,1028,620,644]" class="Bivalvia" family="Gryphaeidae" genus="Nanogyra" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="species" species="nana" subGenus="Nanogyra">
<emphasis id="B94DEAD3C00A4633FCDEFDAEFC623187" box="[801,913,621,644]" italics="true" pageId="19" pageNumber="20">Nanogyra</emphasis>
(
<emphasis id="B94DEAD3C00A4633FC5DFDAEFC4F3187" box="[930,956,621,644]" italics="true" pageId="19" pageNumber="20">N.</emphasis>
) 
<emphasis id="B94DEAD3C00A4633FC33FDAEFBF73187" box="[972,1028,621,644]" italics="true" pageId="19" pageNumber="20">nana</emphasis>
</taxonomicName>
attached on the outer surface of the same 
<taxonomicName id="4C394D42C00A4633FF28FD4CFECA31AB" box="[215,313,655,680]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FF28FD4CFECA31AB" box="[215,313,655,680]" italics="true" pageId="19" pageNumber="20">Trichites</emphasis>
</taxonomicName>
shell (Pl. 6.1a 
<emphasis id="B94DEAD3C00A4633FE25FD4CFE1B31AB" bold="true" box="[474,488,655,680]" pageId="19" pageNumber="20">–</emphasis>
c).
</paragraph>
<caption id="DF466649C00A4633FF68F8CEFCE63462" httpUri="https://zenodo.org/record/288042/files/figure.png" pageId="19" pageNumber="20" targetBox="[160,1427,747,1777]" targetPageId="19">
<paragraph id="8B8636C1C00A4633FF68F8CEFCE63462" blockId="19.[151,1436,1805,1889]" pageId="19" pageNumber="20">
<emphasis id="B94DEAD3C00A4633FF68F8CEFEFD3420" bold="true" box="[151,270,1805,1827]" pageId="19" pageNumber="20">FIGURE 8</emphasis>
. 
<taxonomicName id="4C394D42C00A4633FEE3F8CEFE713420" box="[284,386,1805,1827]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00A4633FEE3F8CEFE713420" box="[284,386,1805,1827]" italics="true" pageId="19" pageNumber="20">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00A4633FE74F8CEFE273420" box="[395,468,1805,1827]" pageId="19" pageNumber="20" rank="genus">
<emphasis id="B94DEAD3C00A4633FE74F8CEFE273420" bold="true" box="[395,468,1805,1827]" pageId="19" pageNumber="20">n. gen.</emphasis>
</taxonomicNameLabel>
<taxonomicName id="4C394D42C00A4633FE23F8CEFCF13420" authority="Contejean, 1859" authorityName="Contejean" authorityYear="1859" box="[476,770,1805,1827]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="19" pageNumber="20" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00A4633FE23F8CEFDCC3420" box="[476,575,1805,1827]" italics="true" pageId="19" pageNumber="20">cotyledon</emphasis>
(Contejean, 1859)
</taxonomicName>
. Group of juvenile LVs attached interior, of a bivalved 
<taxonomicName id="4C394D42C00A4633FABCF8CEFA6F3420" box="[1347,1436,1805,1827]" class="Bivalvia" family="Pinnidae" genus="Trichites" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="19" pageNumber="20" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00A4633FABCF8CEFA6F3420" box="[1347,1436,1805,1827]" italics="true" pageId="19" pageNumber="20">Trichites</emphasis>
</taxonomicName>
(CGN-ALO009-1, largest oyster specimens labelled from I-IV, see also Fig. 6), close to its ventral margin; Alombre aux Vaches (Canton Jura), Lower Kimmeridgian, Banné Marls. Scale x1.5.
</paragraph>
</caption>
<paragraph id="8B8636C1C00A4633FF38F84EFEF734ED" blockId="19.[151,1436,1933,2030]" pageId="19" pageNumber="20">
<emphasis id="B94DEAD3C00A4633FF38F84EFEA034A5" bold="true" box="[199,339,1933,1958]" pageId="19" pageNumber="20">Occurrence</emphasis>
. Upper Oxfordian to Upper Kimmeridgian of the Reuchenette Formation in 
<collectingCountry id="F32E7651C00A4633FB3FF84EFABA34A5" box="[1216,1353,1933,1958]" name="Switzerland" pageId="19" pageNumber="20">Switzerland</collectingCountry>
; Upper Oxfordian–Kimmeridgian in 
<collectingCountry id="F32E7651C00A4633FE1FF871FDC334CA" box="[480,560,1970,1993]" name="France" pageId="19" pageNumber="20">France</collectingCountry>
; Kimmeridgian in 
<collectingCountry id="F32E7651C00A4633FCFBF871FC9E34C9" box="[772,877,1970,1994]" name="Germany" pageId="19" pageNumber="20">Germany</collectingCountry>
, 
<collectingCountry id="F32E7651C00A4633FC86F872FC3934C9" box="[889,970,1969,1994]" name="Poland" pageId="19" pageNumber="20">Poland</collectingCountry>
, 
<collectingCountry id="F32E7651C00A4633FC2AF872FBD334C9" box="[981,1056,1969,1994]" name="Russia" pageId="19" pageNumber="20">Russia</collectingCountry>
(Crimea); Tithonian in the 
<collectingCountry id="F32E7651C00A4633FAA9F872FEF334ED" name="Czech Republic" pageId="19" pageNumber="20">Czech Republic</collectingCountry>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FF54FD8033FB" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
<emphasis id="B94DEAD3C00D4634FF38FF54FE9633B3" bold="true" box="[199,357,151,176]" pageId="20" pageNumber="21">Comparisons</emphasis>
. The generic assignment of species discussed below remains tentative. The first three species could belong to 
<taxonomicName id="4C394D42C00D4634FEA8FF7FFE3B33D6" box="[343,456,188,213]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="112" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00D4634FEA8FF7FFE3B33D6" box="[343,456,188,213]" italics="true" pageId="20" pageNumber="21">Circunula</emphasis>
</taxonomicName>
, but there is no evidence of chomata, so far. Several more 
<taxonomicName id="4C394D42C00D4634FB7BFF7EFB1333D7" box="[1156,1248,189,212]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FB7BFF7EFB1333D7" box="[1156,1248,189,212]" italics="true" pageId="20" pageNumber="21">Liostrea</emphasis>
</taxonomicName>
-like species are discussed afterwards in alphabetical order.
</paragraph>
</subSubSection>
<subSubSection id="C323654AC00D4634FF38FEC6FB1234EC" pageId="20" pageNumber="21" type="reference_group">
<paragraph id="8B8636C1C00D4634FF38FEC6FCC23266" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
<taxonomicName id="4C394D42C00D4634FF38FEC6FD7A321E" authority="Cox, 1952" authorityName="Cox" authorityYear="1952" box="[199,649,260,285]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="stoliczkai" subGenus="Catinula">
<emphasis id="B94DEAD3C00D4634FF38FEC6FED0321F" box="[199,291,261,284]" italics="true" pageId="20" pageNumber="21">Liostrea</emphasis>
(
<emphasis id="B94DEAD3C00D4634FECCFEC7FE66321E" box="[307,405,260,285]" italics="true" pageId="20" pageNumber="21">Catinula</emphasis>
) 
<emphasis id="B94DEAD3C00D4634FE5BFEC7FDFD321E" box="[420,526,260,285]" italics="true" pageId="20" pageNumber="21">stoliczkai</emphasis>
<bibRefCitation id="EFA84B30C00D4634FDEAFEC7FD7A321E" author="Cox" box="[533,649,260,285]" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952">Cox, 1952</bibRefCitation>
</taxonomicName>
(p. 75, pl. 6, figs. 5–6)—This species was originally described by 
<bibRefCitation id="EFA84B30C00D4634FA92FEC7FF123243" author="Cox" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952">Cox (1952)</bibRefCitation>
from the Upper Bathonian of Soorkha (Kutch district, Gujarat, 
<collectingCountry id="F32E7651C00D4634FC33FEE4FBF93243" box="[972,1034,295,320]" name="India" pageId="20" pageNumber="21">India</collectingCountry>
). Morphological similarity with 
<taxonomicName id="4C394D42C00D4634FA7DFEEBFEF73266" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FA7DFEEBFEF73266" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
may indicate that the two species are congeneric.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FEACFCCF313F" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
The species differs by having a tendency to develop a more quadrate 
<taxonomicName id="4C394D42C00D4634FC2EFEACFBD1328B" box="[977,1058,367,392]" class="Bivalvia" family="Ostreidae" genus="Actinostreon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="outline">outline</taxonomicName>
, by being more strongly reflected upwards and growing higher ventrally (up to 
<emphasis id="B94DEAD3C00D4634FD58FE56FD3232AF" box="[679,705,405,428]" italics="true" pageId="20" pageNumber="21">ca</emphasis>
. 
<quantity id="4CC19B24C00D4634FD2CFE57FCE232AF" box="[723,785,404,428]" metricMagnitude="-2" metricUnit="m" metricValue="4.0" pageId="20" pageNumber="21" unit="cm" value="4.0">4 cm</quantity>
; fide 
<bibRefCitation id="EFA84B30C00D4634FCABFE57FC3B32AE" author="Cox" box="[852,968,404,429]" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952">Cox 1952</bibRefCitation>
, p. 75). The RV shows better developed antimarginal riblets, occasionally also radial furrows which reach near the ventral margin, and commarginally arranged tiny pustules (
<bibRefCitation id="EFA84B30C00D4634FE5DFE1FFD4032F6" author="Cox" box="[418,691,476,501]" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952" yearSuffix="a">Cox 1952, pl. 6, fig. 6a</bibRefCitation>
). Remains of such pustules in 
<taxonomicName id="4C394D42C00D4634FBECFE1EFB5132F6" box="[1043,1186,476,501]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FBECFE1EFB5132F6" box="[1043,1186,476,501]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
are only known from juvenile LVs (Fig. 6.1, 3; Pl. 3.3b,c,e). Judging from the figured LV in 
<bibRefCitation id="EFA84B30C00D4634FC4AFDC3FB23311B" author="Cox" box="[949,1232,511,536]" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952" yearSuffix="b">Cox (1952, pl. 6, fig. 6b)</bibRefCitation>
, the PAM appears to be larger and more centrally situated than in 
<taxonomicName id="4C394D42C00D4634FD57FDE6FCC6313E" box="[680,821,548,573]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FD57FDE6FCC6313E" box="[680,821,548,573]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FD8BFD4631CF" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
&quot; 
<taxonomicName id="4C394D42C00D4634FF2DFD8AFEDD3163" box="[210,302,585,608]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FF2DFD8AFEDD3163" box="[210,302,585,608]" italics="true" pageId="20" pageNumber="21">Liostrea</emphasis>
</taxonomicName>
&quot; 
<emphasis id="B94DEAD3C00D4634FEBCFD84FE303163" box="[323,451,583,608]" italics="true" pageId="20" pageNumber="21">strigilecula</emphasis>
(
<bibRefCitation id="EFA84B30C00D4634FE2CFD84FD903163" author="White" box="[467,611,583,608]" pageId="20" pageNumber="21" refString="White, C. A. (1877) Report upon the invertebrate fossils collected in portions of Nevada, Utah, Colorado, New Mexico, and Arizona. Geographical Surveys west of the 100 th Meridian (U. S.), 4 (1), 1 - 219 pp." type="journal article" year="1877">White, 1877</bibRefCitation>
) (p. 163, pl. 8, fig. 3a–d)—This species was described from the Middle Jurassic Carmel Formation in SW Utah. It has a much larger adductor and a more inflated LV than 
<taxonomicName id="4C394D42C00D4634FB10FDAEFA8E3186" box="[1263,1405,620,645]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FB10FDAEFA8E3186" box="[1263,1405,620,645]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
. It produces free-rolling oyster accumulations (ostreoliths) in shallow marine environments and also grows on hardgrounds (
<bibRefCitation id="EFA84B30C00D4634FECEFD77FDF031CF" author="Wilson" box="[305,515,692,717]" pageId="20" pageNumber="21" refString="Wilson, M. A., Ozanne, C. R. &amp; Palmer, T. J. (1998) Origin and paleoecology of free-rolling oyster accumulations (ostreoliths) in the Middle Jurassic of southwestern Utah, USA. Palaios, 13 (1), 70 - 78. http: // dx. doi. org / 10.2307 / 3515282" type="journal article" year="1998">
Wilson 
<emphasis id="B94DEAD3C00D4634FE75FD76FE3131CE" box="[394,450,692,717]" italics="true" pageId="20" pageNumber="21">et al.</emphasis>
1998
</bibRefCitation>
, p. 73, fig. 4A).
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FD1BFE253034" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
“ 
<taxonomicName id="4C394D42C00D4634FF2CFD1BFEED31EC" box="[211,286,728,751]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FF2CFD1BFEED31EC" box="[211,286,728,751]" italics="true" pageId="20" pageNumber="21">Ostrea</emphasis>
</taxonomicName>
” 
<emphasis id="B94DEAD3C00D4634FECCFD14FE6031F3" box="[307,403,727,752]" italics="true" pageId="20" pageNumber="21">planaria</emphasis>
Rollier, 1917 (p. 550, pl. 39, figs. 1a–c)—The species comes from the &quot;Terrain à Chailles&quot; (Lower Oxfordian, 
<emphasis id="B94DEAD3C00D4634FE8BFD3FFE273016" box="[372,468,764,789]" italics="true" pageId="20" pageNumber="21">cordatus</emphasis>
Zone) of the ancient &quot;Bisthum Basel&quot; (
<collectingCountry id="F32E7651C00D4634FC65FD3FFBD03016" box="[922,1059,764,789]" name="Switzerland" pageId="20" pageNumber="21">Switzerland</collectingCountry>
) and the environment of Ferrette (Pfirt) in the Alsace, 
<collectingCountry id="F32E7651C00D4634FE7DFCE3FE213034" box="[386,466,800,823]" name="France" pageId="20" pageNumber="21">France</collectingCountry>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FC87FA7030EA" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
The specimen figured in Rollier (1917) has a smaller attachment area and the ventral margin is less towering than in 
<taxonomicName id="4C394D42C00D4634FF0FFCABFE723083" box="[240,385,871,896]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FF0FFCABFE723083" box="[240,385,871,896]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
. Both sides of the complete specimen are encrusted by serpulids and several specimens of 
<taxonomicName id="4C394D42C00D4634FF68FC4FFEF430A0" box="[151,263,908,931]" class="Bivalvia" family="Gryphaeidae" genus="Nanogyra" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FF68FC4FFEF430A0" box="[151,263,908,931]" italics="true" pageId="20" pageNumber="21">Nanogyra</emphasis>
</taxonomicName>
(probably 
<taxonomicName id="4C394D42C00D4634FE72FC4FFE1F30A0" box="[397,492,908,931]" class="Bivalvia" family="Gryphaeidae" genus="Nanogyra" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="nana">
<emphasis id="B94DEAD3C00D4634FE72FC4FFE1F30A0" box="[397,492,908,931]" italics="true" pageId="20" pageNumber="21">N. nana</emphasis>
</taxonomicName>
) suggesting a life mode under low energy conditions. Small, poorly preserved 
<taxonomicName id="4C394D42C00D4634FF68FC6DFEFB30C4" box="[151,264,942,967]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="112" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00D4634FF68FC6DFEFB30C4" box="[151,264,942,967]" italics="true" pageId="20" pageNumber="21">Circunula</emphasis>
</taxonomicName>
-like shells found by the author attached to corals in the somewhat younger marls and limestones of the Liesberg Member (N 
<collectingCountry id="F32E7651C00D4634FE75FC12FDE130E9" box="[394,530,977,1002]" name="Switzerland" pageId="20" pageNumber="21">Switzerland</collectingCountry>
) probably belong to the same species. It may be congeneric with 
<taxonomicName id="4C394D42C00D4634FB11FC11FA8F30E9" box="[1262,1404,977,1002]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FB11FC11FA8F30E9" box="[1262,1404,977,1002]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FC35FEFD3774" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
“ 
<taxonomicName id="4C394D42C00D4634FF2CFC35FEED370E" box="[211,286,1014,1037]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FF2CFC35FEED370E" box="[211,286,1014,1037]" italics="true" pageId="20" pageNumber="21">Ostrea</emphasis>
</taxonomicName>
” 
<emphasis id="B94DEAD3C00D4634FECDFC35FE3C370E" box="[306,463,1014,1037]" italics="true" pageId="20" pageNumber="21">matisconensis</emphasis>
<bibRefCitation id="EFA84B30C00D4634FE28FC36FD74370D" author="Lissajous" box="[471,647,1013,1038]" pageId="20" pageNumber="21" refString="Lissajous, M. (1923) Etude sur la faune du Bathonien des environs de Macon. Travaux du Laboratoire de Geologie de la Faculte des Sciences de Lyon, Memoires, 3, 1 - 286." type="journal article" year="1923">Lissajous, 1923</bibRefCitation>
(p. 123, pl. 28, figs. 9–12)—This is a Bathonian species from 
<collectingCountry id="F32E7651C00D4634FAB6FC35FA6A370E" box="[1353,1433,1014,1037]" name="France" pageId="20" pageNumber="21">France</collectingCountry>
. Similar to 
<taxonomicName id="4C394D42C00D4634FEF0FBDAFE6D3732" box="[271,414,1048,1073]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FEF0FBDAFE6D3732" box="[271,414,1048,1073]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
, it has a circular 
<taxonomicName id="4C394D42C00D4634FD9AFBDBFD403732" box="[613,691,1048,1073]" class="Bivalvia" family="Ostreidae" genus="Actinostreon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="outline">outline</taxonomicName>
but it remains much smaller and develops antimarginal riblets on the unattached part of the ventral LV margin. These riblets may indicate an assignment to 
<taxonomicName id="4C394D42C00D4634FB4BFBFFFAE53756" ID-CoL="3JHH" box="[1204,1302,1084,1109]" class="Leotiomycetes" family="Pezizellaceae" genus="Catinula" higherTaxonomySource="CoL" kingdom="Fungi" order="Helotiales" pageId="20" pageNumber="21" phylum="Ascomycota" rank="genus">
<emphasis id="B94DEAD3C00D4634FB4BFBFFFAE53756" box="[1204,1302,1084,1109]" italics="true" pageId="20" pageNumber="21">Catinula</emphasis>
</taxonomicName>
rather than 
<taxonomicName id="4C394D42C00D4634FF68FB9CFEFB377B" box="[151,264,1119,1144]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="112" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00D4634FF68FB9CFEFB377B" box="[151,264,1119,1144]" italics="true" pageId="20" pageNumber="21">Circunula</emphasis>
</taxonomicName>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FB40FCF43629" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
&quot; 
<taxonomicName id="4C394D42C00D4634FF2DFB47FEEE3798" box="[210,285,1156,1179]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FF2DFB47FEEE3798" box="[210,285,1156,1179]" italics="true" pageId="20" pageNumber="21">Ostrea</emphasis>
</taxonomicName>
&quot; 
<emphasis id="B94DEAD3C00D4634FECFFB47FE4B3798" box="[304,440,1156,1179]" italics="true" pageId="20" pageNumber="21">matronensis</emphasis>
de Loriol 
<emphasis id="B94DEAD3C00D4634FDCFFB47FDB53798" box="[560,582,1156,1179]" italics="true" pageId="20" pageNumber="21">in</emphasis>
de 
<bibRefCitation id="EFA84B30C00D4634FD90FB40FC283798" author="Loriol" box="[623,987,1155,1180]" pageId="20" pageNumber="21" refString="Loriol, P. de, Royer, E. &amp; Tombeck, H. (1872) Description geologique et paleontologique des etages jurassiques superieurs de la Haute-Marne. Memoires de la Societe Linneenne de Normandie, 16, 542 pp." type="book" year="1872">Loriol, Tombeck &amp; Royer, 1872</bibRefCitation>
(p. 396, pl. 23, figs. 5–7)—The species occurs in the Portlandian (
<taxonomicName id="4C394D42C00D4634FE3FFB64FD4837BC" authority="Zone, Tithonian" authorityName="Zone, Tithonian" box="[448,699,1190,1215]" class="Magnoliopsida" family="Melastomataceae" genus="Gravesia" kingdom="Plantae" order="Myrtales" pageId="20" pageNumber="21" phylum="Tracheophyta" rank="species" species="gigas">
<emphasis id="B94DEAD3C00D4634FE3FFB64FE0E37BD" box="[448,509,1191,1214]" italics="true" pageId="20" pageNumber="21">gigas</emphasis>
Zone, Tithonian
</taxonomicName>
) of the Department Haute-Marne, 
<collectingCountry id="F32E7651C00D4634FBBDFB64FB6137BD" box="[1090,1170,1191,1214]" name="France" pageId="20" pageNumber="21">France</collectingCountry>
. It is characterized by a less oblique opisthogyrate resilifer and a higher ligament area; the umbo is more prominent and the overall shape tends to be more subtriangular than round. 
<collectingCountry id="F32E7651C00D4634FD7DFB2DFD503606" box="[642,675,1262,1285]" name="South Georgia and the South Sandwich Islands" pageId="20" pageNumber="21">De</collectingCountry>
<bibRefCitation id="EFA84B30C00D4634FD54FB2EFBE63605" author="Loriol" box="[683,1045,1261,1286]" pageId="20" pageNumber="21" refString="Loriol, P. de, Royer, E. &amp; Tombeck, H. (1872) Description geologique et paleontologique des etages jurassiques superieurs de la Haute-Marne. Memoires de la Societe Linneenne de Normandie, 16, 542 pp." type="book" year="1872" yearSuffix="a">Loriol (1872, pl. 23, figs. 6, 6a)</bibRefCitation>
figured a specimen attached to an ammonite, but otherwise settling grounds are unknown.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FAF6FE8E36D9" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
? 
<taxonomicName id="4C394D42C00D4634FF2CFAF6FD84364E" authority="Buvignier, 1852" authorityName="Buvignier" authorityYear="1852" box="[211,631,1332,1357]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="moreana">
<emphasis id="B94DEAD3C00D4634FF2CFAF6FE6C364E" box="[211,415,1333,1357]" italics="true" pageId="20" pageNumber="21">Liostrea moreana</emphasis>
(
<bibRefCitation id="EFA84B30C00D4634FE4DFAF7FD9C364E" author="Buvignier" box="[434,623,1332,1357]" pageId="20" pageNumber="21" refString="Buvignier, A. (1852) Statistique geologique, mineralogique, minerallurgique et paleontologique du departement de la Meuse, ouvrage accompagne d'un Atlas de 32 planches. Bailliere, Paris, 694 pp. + Atlas 52 pp." type="book" year="1852">Buvignier, 1852</bibRefCitation>
)
</taxonomicName>
(p. 26, pl. 16, figs. 41–43)—This large species (up to 
<quantity id="4CC19B24C00D4634FAEFFAF6FAAF364E" box="[1296,1372,1333,1357]" metricMagnitude="-1" metricUnit="m" metricValue="1.3" pageId="20" pageNumber="21" unit="cm" value="13.0">13 cm</quantity>
) was described from the Oxfordian (“coral rag”) of the 
<collectingCountry id="F32E7651C00D4634FCEBFA9BFCAC366C" box="[788,863,1368,1391]" name="Egypt" pageId="20" pageNumber="21">Meuse</collectingCountry>
Department (Lorraine) in northeastern 
<collectingCountry id="F32E7651C00D4634FAB6FA9BFA6A366C" box="[1353,1433,1368,1391]" name="France" pageId="20" pageNumber="21">France</collectingCountry>
. Differences to 
<taxonomicName id="4C394D42C00D4634FEBFFABFFE3C3697" box="[320,463,1403,1428]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FEBFFABFFE3C3697" box="[320,463,1403,1428]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
are the larger adult size, the more capacious and stronger upward reflected left valve (up to 
<quantity id="4CC19B24C00D4634FF17FA5CFED536B4" box="[232,294,1439,1463]" metricMagnitude="-2" metricUnit="m" metricValue="8.0" pageId="20" pageNumber="21" unit="cm" value="8.0">8 cm</quantity>
), a broader ligament area with a ventrally straight RV hinge margin, and absence of antimarginal ornament on the RV.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38FA25FCF2358F" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
<emphasis id="B94DEAD3C00D4634FF38FA25FEC136FE" box="[199,306,1510,1533]" italics="true" pageId="20" pageNumber="21">
“ 
<taxonomicName id="4C394D42C00D4634FF30FA25FEDB36FE" box="[207,296,1510,1533]" class="Bivalvia" family="Ostreidae" genus="Ostrea" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">Ostrea</taxonomicName>
”
</emphasis>
<taxonomicName id="4C394D42C00D4634FEC6FA26FDAF36FD" authority="Goldfuss, 1833" authorityName="Goldfuss" authorityYear="1833" box="[313,604,1509,1534]" class="Bivalvia" family="Gryphaeidae" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="subTribe" subTribe="Sandalina">
<emphasis id="B94DEAD3C00D4634FEC6FA26FE5436FD" box="[313,423,1509,1534]" italics="true" pageId="20" pageNumber="21">sandalina</emphasis>
Goldfuss, 1833
</taxonomicName>
(b) (pl. 79, figs. 9a–m)—The material from Goldfuss appears to belong to various species. Specimens of figures 9c–d come from a “black Jura-limestone” (Lower? Jurassic) of Osterkappeln and Lübke, NW 
<collectingCountry id="F32E7651C00D4634FEA5F9EEFE353546" box="[346,454,1581,1605]" name="Germany" pageId="20" pageNumber="21">Germany</collectingCountry>
; specimens 9a–b, f–I are from oolitic ferruginous clay stones (probably Bajocian) of Streitberg, Gräfenberg, and Thurnau, Bavaria. Goldfuss also mentioned this species from white Oolites (Upper Jurassic) of Hildesheim and Goslar, northern 
<collectingCountry id="F32E7651C00D4634FD6CF9B7FD0E358F" box="[659,765,1652,1676]" name="Germany" pageId="20" pageNumber="21">Germany</collectingCountry>
.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38F954FB9435F4" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
His specimens of figures 9c–d, h, l–m may indeed belong to 
<taxonomicName id="4C394D42C00D4634FC6DF954FBF035B3" box="[914,1027,1687,1712]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00D4634FC6DF954FBF035B3" box="[914,1027,1687,1712]" italics="true" pageId="20" pageNumber="21">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00D4634FBF2F954FBAD35B3" box="[1037,1118,1687,1712]" pageId="20" pageNumber="21" rank="genus">
<emphasis id="B94DEAD3C00D4634FBF2F954FBAD35B3" bold="true" box="[1037,1118,1687,1712]" pageId="20" pageNumber="21">n. gen.</emphasis>
</taxonomicNameLabel>
whereas figures 
<date id="FF871001C00D4634FAD9F954FAC935B3" box="[1318,1338,1687,1712]" pageId="20" pageNumber="21">9i</date>
–k more likely represent 
<taxonomicName id="4C394D42C00D4634FEA4F97FFE4435D0" box="[347,439,1724,1747]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FEA4F97FFE4435D0" box="[347,439,1724,1747]" italics="true" pageId="20" pageNumber="21">Liostrea</emphasis>
</taxonomicName>
or 
<taxonomicName id="4C394D42C00D4634FE13F97FFD8E35D0" box="[492,637,1724,1747]" class="Bivalvia" family="Gryphaeidae" genus="Praeexogyra" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus">
<emphasis id="B94DEAD3C00D4634FE13F97FFD8E35D0" box="[492,637,1724,1747]" italics="true" pageId="20" pageNumber="21">Praeexogyra</emphasis>
</taxonomicName>
. Compare also specimens tentatively determined as? 
<taxonomicName id="4C394D42C00D4634FAF4F97FFEC035F4" class="Bivalvia" family="Gryphaeidae" genus="Praeexogyra" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="sandalinoides">
<emphasis id="B94DEAD3C00D4634FAF4F97FFEC035F4" italics="true" pageId="20" pageNumber="21">Praeexogyra sandalinoides</emphasis>
</taxonomicName>
(de 
<bibRefCitation id="EFA84B30C00D4634FE9BF91DFE0235F4" author="Loriol" box="[356,497,1758,1783]" pageId="20" pageNumber="21" refString="Loriol, P. de (1901) Etude sur les mollusques et brachiopodes de l'Oxfordien superieur et moyen du Jura Bernois. Supplement 1. (accompagnee d'une notice stratigraphique par E. Koby). Memoires de la Societe paleontologique Suisse, 28, 1 - 119." type="journal article" year="1901">Loriol, 1901</bibRefCitation>
) from the Callovian of Western Pomerania (Pl. 15.3–4).
</paragraph>
<paragraph id="8B8636C1C00D4634FF68F8C1FD9A3486" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
<bibRefCitation id="EFA84B30C00D4634FF68F8C1FD243419" author="Cox" box="[151,727,1793,1818]" pageId="20" pageNumber="21" refString="Cox, L. R. (1952) The Jurassic lamellibranch fauna of Cutch (Kachh). No. 3, Families Pectinidae, Amusiidae, Plicatulidae, Limidae, Ostreidae and Trigoniidae (Supplement). Memoirs of the Geological Survey of India, Palaeontologica Indica, Series 9, 3 (4), 1 - 128." type="journal article" year="1952" yearSuffix="p">Cox (1952, p. 73, pl. 6, figs. 1–4, with synonymies)</bibRefCitation>
described material from the Bathonian of 
<collectingCountry id="F32E7651C00D4634FB50F8C2FB1A3419" box="[1199,1257,1793,1818]" name="India" pageId="20" pageNumber="21">India</collectingCountry>
and determined the species as 
<taxonomicName id="4C394D42C00D4634FEC1F8E5FD63343E" box="[318,656,1828,1853]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="sandalina" subGenus="Catinula">
<emphasis id="B94DEAD3C00D4634FEC1F8E5FE68343E" box="[318,411,1830,1853]" italics="true" pageId="20" pageNumber="21">Liostrea</emphasis>
(
<emphasis id="B94DEAD3C00D4634FE52F8E7FDFC343E" box="[429,527,1828,1853]" italics="true" pageId="20" pageNumber="21">Catinula</emphasis>
) 
<emphasis id="B94DEAD3C00D4634FDDDF8E7FD63343E" box="[546,656,1828,1853]" italics="true" pageId="20" pageNumber="21">sandalina</emphasis>
</taxonomicName>
. However, typical specimens with a large attachment area and oval 
<taxonomicName id="4C394D42C00D4634FF68F88BFF163462" box="[151,229,1864,1889]" class="Bivalvia" family="Ostreidae" genus="Actinostreon" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreoida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="outline">outline</taxonomicName>
differ from 
<taxonomicName id="4C394D42C00D4634FE8BF88AFDF03462" box="[372,515,1864,1889]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="cotyledon">
<emphasis id="B94DEAD3C00D4634FE8BF88AFDF03462" box="[372,515,1864,1889]" italics="true" pageId="20" pageNumber="21">C. cotyledon</emphasis>
</taxonomicName>
by a smaller adult height (around 
<quantity id="4CC19B24C00D4634FC6DF88AFC3C3462" box="[914,975,1865,1889]" metricMagnitude="-2" metricUnit="m" metricValue="3.0" pageId="20" pageNumber="21" unit="cm" value="3.0">3 cm</quantity>
), a less orbicular shape and a somewhat stronger upward reflected ventral margin.
</paragraph>
<paragraph id="8B8636C1C00D4634FF38F853FB1234EC" blockId="20.[151,1437,151,2031]" pageId="20" pageNumber="21">
<taxonomicName id="4C394D42C00D4634FF38F853FDE634AB" authority="Chavan, 1952" authorityName="Chavan" authorityYear="1952" box="[199,533,1935,1960]" class="Bivalvia" family="Gryphaeidae" genus="Liostrea" higherTaxonomySource="GBIF" kingdom="Animalia" order="Pterioida" pageId="20" pageNumber="21" phylum="Mollusca" rank="species" species="brasili">
<emphasis id="B94DEAD3C00D4634FF38F853FE8034AB" box="[199,371,1935,1960]" italics="true" pageId="20" pageNumber="21">Liostrea brasili</emphasis>
<bibRefCitation id="EFA84B30C00D4634FE85F84CFDE634AB" author="Chavan" box="[378,533,1935,1960]" pageId="20" pageNumber="21" refString="Chavan, A. (1952) Les pelecypodes des sables astartiens de Cordebugle (Calvados). Memoires de la Societe Paleontologique Suisse, 69, 1 - 132." type="journal article" year="1952">Chavan, 1952</bibRefCitation>
</taxonomicName>
(p. 43, pl. 2, fig. 22)—The species from the Oxfordian of Calvados (
<collectingCountry id="F32E7651C00D4634FAE7F853FA9B34AB" box="[1304,1384,1936,1960]" name="France" pageId="20" pageNumber="21">France</collectingCountry>
) has a similar shape, but a triangular ostreoid hinge, with a broad resilifer and a ventrally convex hinge line. It also has a well-developed umbonal cavity (
<bibRefCitation id="EFA84B30C00D4634FDF9F815FCC434EC" author="Chavan" box="[518,823,2006,2031]" pageId="20" pageNumber="21" refString="Chavan, A. (1952) Les pelecypodes des sables astartiens de Cordebugle (Calvados). Memoires de la Societe Paleontologique Suisse, 69, 1 - 132." type="journal article" year="1952">Chavan 1952, pl. 2, fig. 22</bibRefCitation>
), which is absent in 
<taxonomicName id="4C394D42C00D4634FBE4F815FB7F34EC" box="[1051,1164,2006,2031]" class="Bivalvia" family="Arctostreidae" genus="Circunula" higherTaxonomySource="GBIF" kingdom="Animalia" order="Ostreida" pageId="20" pageNumber="21" phylum="Mollusca" rank="genus" status="gen. nov.">
<emphasis id="B94DEAD3C00D4634FBE4F815FB7F34EC" box="[1051,1164,2006,2031]" italics="true" pageId="20" pageNumber="21">Circunula</emphasis>
</taxonomicName>
<taxonomicNameLabel id="A27E57A8C00D4634FB6CF815FB1234EC" box="[1171,1249,2006,2031]" pageId="20" pageNumber="21" rank="genus">
<emphasis id="B94DEAD3C00D4634FB6CF815FB1234EC" bold="true" box="[1171,1249,2006,2031]" pageId="20" pageNumber="21">n. gen.</emphasis>
</taxonomicNameLabel>
</paragraph>
</subSubSection>
</treatment>
</document>