<documentid="1A6ABA5D2D241D4C373C4474123D1434"ID-CLB-Dataset="298388"ID-DOI="10.5194/fr-18-81-2015"ID-GBIF-Dataset="49a593d2-44ce-420d-a608-8533ec6745ac"ID-ISSN="2193-0074"ID-Zenodo-Dep="11585625"IM.bibliography_approvedBy="carolina"IM.illustrations_approvedBy="carolina"IM.materialsCitations_approvedBy="carolina"IM.metadata_approvedBy="felipe"IM.tables_approvedBy="carolina"IM.taxonomicNames_approvedBy="carolina"IM.treatments_approvedBy="carolina"checkinTime="1716844663622"checkinUser="felipe"docAuthor="Titus, A. L., Korn, D., Harrell, J. E. & Lambert, L. L."docDate="2015"docId="039287BEFC5BFFA5FFA9FC24FD37FD5E"docLanguage="en"docName="FossRec.18.2.81-104.pdf"docOrigin="Fossil Record 18 (2)"docSource="http://dx.doi.org/10.5194/fr-18-81-2015"docStyle="DocumentStyle:1B3764FFAC190C6D25C29F616DE4358D.2:FossRec.2014-2021.journal_article"docStyleId="1B3764FFAC190C6D25C29F616DE4358D"docStyleName="FossRec.2014-2021.journal_article"docStyleVersion="2"docTitle="Girtyoceras meslerianum"docType="treatment"docVersion="7"lastPageNumber="88"masterDocId="FFABFFC6FC5CFFACFFD5FFF5FFC9FF94"masterDocTitle="Late Viséan (late Mississippian) ammonoids from the Barnett Shale, Sierra Diablo Escarpment, Culberson County, Texas, USA"masterLastPageNumber="104"masterPageNumber="81"pageNumber="88"updateTime="1718152557931"updateUser="ExternalLinkService"zenodo-license-document="CC-BY-4.0">
<mods:titleid="2E061B14CD22684C43426AFEC41EFF2B">Late Viséan (late Mississippian) ammonoids from the Barnett Shale, Sierra Diablo Escarpment, Culberson County, Texas, USA</mods:title>
<mods:namePartid="ED564A5465FA61DF20F2ACDF7B51CE0A">Titus, A. L.</mods:namePart>
<mods:affiliationid="F1E95B85A00244F78309BC8556EF74AA">D. Korn & Grand Staircase-Escalante National Monument, 669 S. Highway 89 A, Kanab, UT 84741, USA</mods:affiliation>
<mods:affiliationid="EFE8B663B9435273D70D7498793E497E">J. E. Harrell & Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstrasse 43,</mods:affiliation>
<mods:namePartid="3F123FE6FF986E975B904625F37F4B79">Lambert, L. L.</mods:namePart>
<mods:affiliationid="2CB1A0008E8BE4C0AB16555FAC7DE0AB">Department of Geological Sciences, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA</mods:affiliation>
<bibRefCitationid="EFAA4B59FC5BFFABFE4AFC24FDE8FC7D"author="Girty, G. H."box="[415,545,977,1001]"pageId="7"pageNumber="88"pagination="1 - 106"refId="ref16650"refString="Girty, G. H.: The fauna of the Caney Shale of Oklahoma, Bulletin of the U. S. Geological Survey, 377, 1 - 106, 1909."type="journal article"year="1909">Girty, 1909</bibRefCitation>
)
</taxonomicName>
(
<figureCitationid="13002A2DFC5BFFABFDE3FC24FD48FC7D"box="[566,641,977,1001]"captionStart="Figure 6"captionStartId="7.[124,191,513,535]"captionTargetBox="[214,677,181,479]"captionTargetId="figure-15@7.[210,680,177,482]"captionTargetPageId="7"captionText="Figure 6. Girtyoceras meslerianum (Girty, 1909) from the Figure 2 Ranch section, Sierra Diablo. Specimen NPL 68364 from bed 17 (sample 00TXCU-25); × 4.0."figureDoi="http://doi.org/10.5281/zenodo.11585637"httpUri="https://zenodo.org/record/11585637/files/figure.png"pageId="7"pageNumber="88">Figs. 6</figureCitation>
and
<figureCitationid="13002A2DFC5BFFABFD6CFC24FD0EFC7D"box="[697,711,977,1001]"captionStart="Figure 7"captionStartId="8.[124,191,1506,1528]"captionTargetBox="[312,1256,657,1479]"captionTargetId="graphics-319@8.[770,1176,946,1165]"captionTargetPageId="8"captionText="Figure 7. Girtyoceras meslerianum (Girty, 1909), conch cross sections and ontogenetic trajectories of material from the Caney Shale of Jackfork Creek near Ada, Oklahoma (a–d). (a) Specimen MB.C.25466; × 2.5. (b) Specimen MB.C.25467; × 2.5. (c) Specimen MB.C.25468; × 2.5. (d) Specimen MB.C.25469; × 2.5. (e–g), ontogenetic development of the conch width index (ww / dm), umbilical width index (uw / dm), and WER of the sectioned specimens and type material."figureDoi="http://doi.org/10.5281/zenodo.11585639"httpUri="https://zenodo.org/record/11585639/files/figure.png"pageId="7"pageNumber="88">7</figureCitation>
<specimenCodeid="DB9D9ED3FC5BFFABFEBCFAF9FDDFFAB7"box="[361,534,1292,1315]"collectionCode="USNM"country="USA"httpUri="http://biocol.org/urn:lsid:biocol.org:col:34871"lsid="urn:lsid:biocol.org:col:34871"name="Smithsonian Institution, National Museum of Natural History"pageId="7"pageNumber="88"type="Museum">USNM 119594</specimenCode>
; illustrated by
<bibRefCitationid="EFAA4B59FC5BFFABFD13FAF9FF74FAD7"author="Girty, G. H."pageId="7"pageNumber="88"pagination="1 - 106"refId="ref16650"refString="Girty, G. H.: The fauna of the Caney Shale of Oklahoma, Bulletin of the U. S. Geological Survey, 377, 1 - 106, 1909."type="journal article"year="1909">Girty (1909</bibRefCitation>
<collectionCodeid="ED2AAE6DFC5BFFABFD03FAB9FD21FAF7"box="[726,744,1356,1379]"name="Tavera, Department of Geology and Geophysics"pageId="7"pageNumber="88">T</collectionCode>
. 2 S.,
<collectionCodeid="ED2AAE6DFC5BFFABFF4BFA99FF7AFA17"box="[158,179,1388,1411]"country="Chile"name="Departamento de Geologia, Universidad de Chile"pageId="7"pageNumber="88">R</collectionCode>
. 7 E., northwest of Wapanucka, Johnston County,
<collectingRegionid="49FFF84AFC5BFFABFD17FA99FF73FA37"country="United States of America"name="Oklahoma"pageId="7"pageNumber="88">Oklahoma</collectingRegion>
;
<collectingRegionid="49FFF84AFC5BFFABFF13FA79FEE2FA37"box="[198,299,1420,1443]"country="United States of America"name="Delaware"pageId="7"pageNumber="88">Delaware</collectingRegion>
<specimenCodeid="DB9D9ED3FC5BFFABFDF4FA3EFD68FA76"box="[545,673,1483,1506]"collectionCode="NPL"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL 68364</specimenCode>
through
<specimenCodeid="DB9D9ED3FC5BFFABFFA9FA1EFF30F996"box="[124,249,1515,1538]"collectionCode="NPL"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL 68366</specimenCode>
diameter) with acute venter. Ornament with sharp riblets in the juvenile stage; coarse prorsiradiate growth lines with concavo-convex course in the intermediate stage and fine biconvex growth lines in the adult stage. Strong shell constrictions in intermediate growth stages.
are all mostly testiferous. No sutures are visible. The specimen that represents the largest diameter (
<collectionCodeid="ED2AAE6DFC5BFFABFC3BFEC5FBEBFED3"box="[1006,1058,304,327]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL</collectionCode>
68366) is only a whorl fragment and poorly preserved. However, it represents a specimen that is clearly advanced over
<collectionCodeid="ED2AAE6DFC5BFFABFBF6FE85FB9CFE13"box="[1059,1109,368,391]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL</collectionCode>
The better preserved of the two larger specimens (
<collectionCodeid="ED2AAE6DFC5BFFABFA57FE3AFA7FFE72"box="[1410,1462,463,486]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL</collectionCode>
diameter the umbilical margin forms a strong right angle and the ribs and constrictions (which number four per whorl, are moderately deep and visible on both the internal moulds and external shell) are very strongly deflected anteriorly. The ribs and constrictions also form a distinct ventral sulcus at this stage. Faint longitudinal lines can be seen in the ventral area.
<collectionCodeid="ED2AAE6DFC5BFFABFB9AFD3BFB4AFD71"box="[1103,1155,718,741]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="7"pageNumber="88"type="University or college">NPL</collectionCode>
68365) is transitioning from the widely umbilicate acutely marginated form to the almost parallel-sided thickly discoidal form with a 90
umbilical shoulder. The flanks and venter are gently rounded. Fine thread-like riblets originate from the umbilical margin and deflect anteriorly at the ventrolateral margin. The ribs are straight across the venter.
is a rare taxon in the Sierra Diablo sections mostly because well-preserved three-dimensional material is difficult to obtain from the concretions that bear its assemblage. Although interpreted rather broadly in the past, in our view,
<taxonomicNameid="4C3B4D2BFC5BFFABFBBBFBB9FAD4FBF0"authorityName="Korn and Titus"authorityYear="2011"box="[1134,1309,1100,1124]"class="Cephalopoda"family="Girtyoceratidae"genus="Girtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="hamiltonense">
<taxonomicNameid="4C3B4D2BFC5BFFABFB98FB99FA95FB10"baseAuthorityName="Miller and Faber"baseAuthorityYear="1892"box="[1101,1372,1132,1156]"class="Cephalopoda"family="Girtyoceratidae"genus="Sulcogirtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="limatum">
. It bears the more compressed conch form, strongly developed anterior deflection of the ribs and constrictions on the ventrolateral shoulder, and wider umbilicus of the latter (uw / dm = 0.31), but has the weaker ornament and lack of ventrolateral sulcus of the former. Thus
<taxonomicNameid="4C3B4D2BFC5BFFABFC18FAD9FBB2FAD0"authorityName="Korn and Titus"authorityYear="2011"box="[973,1147,1324,1348]"class="Cephalopoda"family="Girtyoceratidae"genus="Girtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="hamiltonense">
<taxonomicNameid="4C3B4D2BFC5BFFABFC0FFABEFB82FAF7"baseAuthorityName="Miller and Faber"baseAuthorityYear="1892"box="[986,1099,1355,1379]"class="Cephalopoda"family="Girtyoceratidae"genus="Sulcogirtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="limatum">
<taxonomicNameid="4C3B4D2BFC5BFFABFB82FA9EFACEFA17"authorityName="Korn and Titus"authorityYear="2011"box="[1111,1287,1387,1411]"class="Cephalopoda"family="Girtyoceratidae"genus="Girtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="hamiltonense">
<taxonomicNameid="4C3B4D2BFC5BFFABFAEDF99FFCA6F936"authorityName="Korn and Titus"authorityYear="2011"class="Cephalopoda"family="Girtyoceratidae"genus="Girtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="hamiltonense">
in North America have less sinuous constrictions and narrower umbilici at comparable diameters (e.g.
<taxonomicNameid="4C3B4D2BFC5BFFABFAB4F95FFCABF976"authorityName="Korn and Titus"authorityYear="2011"class="Cephalopoda"family="Girtyoceratidae"genus="Girtyoceras"kingdom="Animalia"pageId="7"pageNumber="88"phylum="Mollusca"rank="species"species="gordoni">
<collectingCountryid="F32C7638FC5BFFABFB16F8BFFB31F8F5"box="[1219,1272,1866,1889]"name="United States of America"pageId="7"pageNumber="88">USA</collectingCountry>
and the western Cordillera (Chainman Shale). It is rather uncommon outside of its
area, with the only other definitive occurrences we know of at San
<collectingCountryid="F32C7638FC55FFA5FE8DFDE6FE47FDBE"box="[344,398,531,554]"name="Bonaire, Sint Eustatius and Saba"pageId="9"pageNumber="90">Saba</collectingCountry>
, Texas in the base of the Barnett Formation and in the Chainman Shale at the classic Duckwater locality (not mentioned by
<bibRefCitationid="EFAA4B59FC55FFA5FE3EFDA6FD10FDFE"author="Korn, D. & Titus, A. L."box="[491,729,595,618]"pageId="9"pageNumber="90"pagination="107 - 196"refId="ref17423"refString="Korn, D. and Titus, A. L.: Goniatites Zone (middle Mississippian) ammonoids of the Antler Foreland Basin (Nevada, Utah), Bull. Geosci., 86, 107 - 196, doi: 10.3140 / bull. geosci. 1242, 2011."type="journal article"year="2011">Korn and Titus, 2011</bibRefCitation>
of the upper Pool Creek Member of the Moorefield Formation, but specimens from this interval are all crushed (
<bibRefCitationid="EFAA4B59FC55FFA5FD8CFD46FD3BFD5E"author="Gordon, M. J."box="[601,754,691,714]"pageId="9"pageNumber="90"pagination="1 - 322"refId="ref16774"refString="Gordon, M. J.: Carboniferous Cephalopods of Arkansas, Professional Papers, U. S. Geological Survey, 460, 1 - 322, 1965."type="journal article"year="1965">Gordon, 1965</bibRefCitation>
