<documentid="998DC1162ADD83E3D4C93AAC538A6CDB"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="039287BEFC48FFB8FFA9FEDAFBC4FC11"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="Pachylyroceras cloudi"docType="treatment"docVersion="4"lastPageNumber="101"masterDocId="FFABFFC6FC5CFFACFFD5FFF5FFC9FF94"masterDocTitle="Late Viséan (late Mississippian) ammonoids from the Barnett Shale, Sierra Diablo Escarpment, Culberson County, Texas, USA"masterLastPageNumber="104"masterPageNumber="81"pageNumber="101"updateTime="1718152557931"updateUser="ExternalLinkService"zenodo-license-document="CC-BY-4.0">
<mods:titleid="62F3090DA3DB52A165942962107A9813">Late Viséan (late Mississippian) ammonoids from the Barnett Shale, Sierra Diablo Escarpment, Culberson County, Texas, USA</mods:title>
<mods:namePartid="3A2AAEEAC399DDB00DA966998C9E8E6E">Titus, A. L.</mods:namePart>
<mods:affiliationid="5EDF1607B1DF635DC8DEE65D7AA924F4">D. Korn & Grand Staircase-Escalante National Monument, 669 S. Highway 89 A, Kanab, UT 84741, USA</mods:affiliation>
<mods:affiliationid="677AE99ED15FDD0F4A6FF7DCCCE42511">J. E. Harrell & Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, Invalidenstrasse 43,</mods:affiliation>
<mods:namePartid="2AD8C27C6BB6B45130F78035C40C31D3">Lambert, L. L.</mods:namePart>
<mods:affiliationid="35039A0B65C06605F5531DA0EDB4B0DE">Department of Geological Sciences, The University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249, USA</mods:affiliation>
<taxonomicNameid="4C3B4D2BFC48FFB8FFA9FEDAFD0EFED3"ID-CoL="4BSQ5"authority="(Miller and Youngquist, 1948)"baseAuthorityName="Miller and Youngquist"baseAuthorityYear="1948"box="[124,711,303,327]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"order="Goniatitida"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="cloudi">
<bibRefCitationid="EFAA4B59FC48FFB8FEAEFEDAFD08FED3"author="Miller, A. K. & Youngquist, W."box="[379,705,303,327]"pageId="20"pageNumber="101"pagination="649 - 671"refId="ref18348"refString="Miller, A. K. and Youngquist, W.: The cephalopod fauna of the Mississippian Barnett Formation of Central Texas, J. Paleontol., 22, 649 - 671, 1948."type="journal article"year="1948">Miller and Youngquist, 1948</bibRefCitation>
<figureCitationid="13002A2DFC48FFB8FF56FEBAFECCFEF3"box="[131,261,335,359]"captionStart="Figure 15"captionStartId="19.[819,886,1078,1100]"captionTargetBox="[855,1427,181,1034]"captionTargetId="figure-400@19.[852,1430,177,1047]"captionTargetPageId="19"captionText="Figure 15. Pachylyroceras cloudi (Miller and Youngquist, 1948) from bed 25 (sample 00TXCU-27) of the Figure 2 Ranch section; both × 2.5. (a) Specimen NPL 68540. (b) Specimen NPL 68541."figureDoi="http://doi.org/10.5281/zenodo.11585657"httpUri="https://zenodo.org/record/11585657/files/figure.png"pageId="20"pageNumber="101">Figs. 15a, b</figureCitation>
and
<figureCitationid="13002A2DFC48FFB8FEE8FEBAFEACFEF3"box="[317,357,335,359]"captionStart="Figure 16"captionStartId="21.[124,191,1113,1135]"captionTargetBox="[168,722,505,1075]"captionTargetId="graphics-129@21.[188,652,715,904]"captionTargetPageId="21"captionText="Figure 16. Suture lines of representatives of Pachylyroceras from localities in Utah, Nevada, and Texas; all × 6.0. (a) Pachylyroceras utahensis (Miller et al., 1952), specimen NPL 68561 from Skunk Spring, Utah, at 11.6 mm diameter, 8.3 mm ww, 5.6 mm wh. (b) Pachylyroceras utahensis (Miller et al., 1952), specimen MB.C.25472 from Hamilton Canyon, Nevada, at 9.3 mm ww, 6.1 mm wh. (c) Pachylyroceras cloudi (Miller and Youngquist, 1948), specimen NPL 68542 from bed 25 of the Figure 2 Ranch, Texas, at 13.2 mm ww, 8.0 mm wh."figureDoi="http://doi.org/10.5281/zenodo.11585659"httpUri="https://zenodo.org/record/11585659/files/figure.png"pageId="20"pageNumber="101">16c</figureCitation>
<taxonomicNameid="4C3B4D2BFC48FFB8FF62FE5AFD44FE52"authority="Miller and Youngquist"authorityName="Miller and Youngquist"authorityYear="1948"box="[183,653,431,455]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Lyrogoniatites"kingdom="Animalia"order="Goniatitida"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="cloudi">
<taxonomicNameid="4C3B4D2BFC48FFB8FF1FFD7BFE70FD32"baseAuthorityName="Miller and Youngquist"baseAuthorityYear="1948"box="[202,441,654,678]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"order="Goniatitida"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="cloudi">
<specimenCodeid="DB9D9ED3FC48FFB8FEB3FD1BFDD8FC91"box="[358,529,750,773]"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="20"pageNumber="101"type="Museum">USNM 113011</specimenCode>
; illustrated by
<bibRefCitationid="EFAA4B59FC48FFB8FD69FD1BFEA0FCB1"author="Miller, A. K. & Youngquist, W."pageId="20"pageNumber="101"pagination="649 - 671"refId="ref18348"refString="Miller, A. K. and Youngquist, W.: The cephalopod fauna of the Mississippian Barnett Formation of Central Texas, J. Paleontol., 22, 649 - 671, 1948."type="journal article"year="1948">Miller and Youngquist (1948</bibRefCitation>
<collectingCountryid="F32C7638FC48FFB8FDAAFCDBFD7CFCD1"box="[639,693,814,837]"name="Bonaire, Sint Eustatius and Saba"pageId="20"pageNumber="101">Saba</collectingCountry>
, Texas (Chappel Hill locality); lower portion of Barnett Shale, probably
<taxonomicNameid="4C3B4D2BFC48FFB8FEBBFC78FDD8FC31"authorityName=", Ruzhencev and Bogoslovskaya"authorityYear="1971"box="[366,529,909,933]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"pageId="20"pageNumber="101"phylum="Mollusca"rank="genus">
<specimenCodeid="DB9D9ED3FC48FFB8FEC7FC18FE59FB90"box="[274,400,1005,1028]"collectionCode="NPL"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="20"pageNumber="101"type="University or college">NPL 68540</specimenCode>
through
<specimenCodeid="DB9D9ED3FC48FFB8FE21FC18FDBBFB90"box="[500,626,1005,1028]"collectionCode="NPL"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="20"pageNumber="101"type="University or college">NPL 68560</specimenCode>
). All of the specimens are from the same starved interval and are nearly all black to dark brown coloured phosphatic steinkerns with rare phosphatized shell remains preserved. All show various states of corrosion and dissolution
Description: The earliest whorls are not preserved in the material, but in specimen
<collectionCodeid="ED2AAE6DFC48FFB8FEAFFB39FE65FB77"box="[378,428,1228,1251]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="20"pageNumber="101"type="University or college">NPL</collectionCode>
68540 the conch has achieved a discoidal shape with moderately depressed whorls and a medium width umbilicus (ww / dm = 0.54; uw / dm = 0.30) by
<figureCitationid="13002A2DFC48FFB8FE76FAD9FDCBFAD7"box="[419,514,1324,1347]"captionStart="Figure 15"captionStartId="19.[819,886,1078,1100]"captionTargetBox="[855,1427,181,1034]"captionTargetId="figure-400@19.[852,1430,177,1047]"captionTargetPageId="19"captionText="Figure 15. Pachylyroceras cloudi (Miller and Youngquist, 1948) from bed 25 (sample 00TXCU-27) of the Figure 2 Ranch section; both × 2.5. (a) Specimen NPL 68540. (b) Specimen NPL 68541."figureDoi="http://doi.org/10.5281/zenodo.11585657"httpUri="https://zenodo.org/record/11585657/files/figure.png"pageId="20"pageNumber="101">Fig. 15a</figureCitation>
). The whorl cross section is slightly depressed (ww / wh = 1.41) with a broadly rounded umbilical shoulder and broadly rounded ventral region. The internal mould shows rather prominent constrictions, being rectiradiate at the umbilical margin, and bending rather sharply forward at the ventrolateral shoulder forming a pronounced ventral salient and a shallow ventral sinus. Longitudinal lirae are relatively coarse; 28 can be counted from umbilical shoulder to umbilical shoulder.
<collectionCodeid="ED2AAE6DFC48FFB8FE0FF9BEFDC5F9F6"box="[474,524,1611,1634]"country="USA"httpUri="http://grbio.org/cool/q79f-q0gz"name="University of Texas at Austin"pageId="20"pageNumber="101"type="University or college">NPL</collectionCode>
68542 (phragmocone whorl width of 13.2 mm, whorl height of 8.0 mm) shows a Vshaped external lobe with sinuous flanks and slightly asymmetric prongs. The median saddle has a height of one-third of the external lobe depth. On the flanks follow a bell-shaped ventrolateral saddle and a symmetric adventive lobe with slightly convex flanks (
<figureCitationid="13002A2DFC48FFB8FEA7F8FFFE04F8B5"box="[370,461,1802,1825]"captionStart="Figure 16"captionStartId="21.[124,191,1113,1135]"captionTargetBox="[168,722,505,1075]"captionTargetId="graphics-129@21.[188,652,715,904]"captionTargetPageId="21"captionText="Figure 16. Suture lines of representatives of Pachylyroceras from localities in Utah, Nevada, and Texas; all × 6.0. (a) Pachylyroceras utahensis (Miller et al., 1952), specimen NPL 68561 from Skunk Spring, Utah, at 11.6 mm diameter, 8.3 mm ww, 5.6 mm wh. (b) Pachylyroceras utahensis (Miller et al., 1952), specimen MB.C.25472 from Hamilton Canyon, Nevada, at 9.3 mm ww, 6.1 mm wh. (c) Pachylyroceras cloudi (Miller and Youngquist, 1948), specimen NPL 68542 from bed 25 of the Figure 2 Ranch, Texas, at 13.2 mm ww, 8.0 mm wh."figureDoi="http://doi.org/10.5281/zenodo.11585659"httpUri="https://zenodo.org/record/11585659/files/figure.png"pageId="20"pageNumber="101">Fig. 16c</figureCitation>
<taxonomicNameid="4C3B4D2BFC48FFB8FDE0F8DFFD11F8D6"authorityName=", Ruzhencev and Bogoslovskaya"authorityYear="1971"box="[565,728,1834,1858]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"pageId="20"pageNumber="101"phylum="Mollusca"rank="genus">
appears to represent only a single species, with all specimens being very close to each other in ornament and morphology. They are also close, in their conch width/diameter and umbilical width ratios, to several of the
<collectingCountryid="F32C7638FC48FFB8FC4AFF05FC1FFE93"box="[927,982,240,263]"name="Bonaire, Sint Eustatius and Saba"pageId="20"pageNumber="101">Saba</collectingCountry>
. As has been pointed out by
<bibRefCitationid="EFAA4B59FC48FFB8FADAFF05FA7BFE93"author="Gordon, M. J."box="[1295,1458,240,263]"pageId="20"pageNumber="101"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>
<bibRefCitationid="EFAA4B59FC48FFB8FC8AFE85FC3CFE13"author="Gordon, M. J."box="[863,1013,368,391]"pageId="20"pageNumber="101"pagination="133 - 151"refId="ref16718"refString="Gordon, M. J.: Some American Midcontinent Carboniferous Cephalopods, J. Paleontol., 34, 133 - 151, 1960."type="journal article"year="1960">Gordon, 1960</bibRefCitation>
, and these differences may be the result of later ontogenetic changes or strong variation rather than of taxonomic value. Unfortunately, because the type lot was collected from ex situ nodules and has no detailed stratigraphic context, it is possible that the type lot is from a different horizon.
<bibRefCitationid="EFAA4B59FC48FFB8FC69FDBAFA9FFDF2"author="Ruzhencev, V. E. & Bogoslovskaya, M. F."box="[956,1366,591,614]"pageId="20"pageNumber="101"pagination="1 - 382"refId="ref18853"refString="Ruzhencev, V. E. and Bogoslovskaya, M. F.: Namyurskiy etap v evolyutsii ammonodey. Rannenamyurskiye ammonoidei., Trudy Paleontologicheskogo Instituta Akademiya Nauk SSSR, 133, 1 - 382, 1971."type="journal article"year="1971">Ruzhencev and Bogoslovskaya (1971)</bibRefCitation>
reported the species from the South Urals, but we consider this assignment erroneous because the conch shape, suture, and ornament of the Uralian forms are fundamentally different from the
<taxonomicNameid="4C3B4D2BFC48FFB8FC7CFD3BFBCDFD72"baseAuthorityName="Miller and Youngquist"baseAuthorityYear="1948"box="[937,1028,718,742]"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="cloudi">
<taxonomicNameid="4C3B4D2BFC48FFB8FAFCFD3BFC50FC92"authorityName="Titus & Korn & Harrell & Lambert"authorityYear="2015"class="Cephalopoda"family="Neoglyphioceratidae"genus="Uralyroceras"kingdom="Animalia"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="arquatum">
(named after the arched course of the constrictions) for the Uralian species (see below).
<taxonomicNameid="4C3B4D2BFC48FFB8FAC6FCFBFCBCFCD1"baseAuthorityName="Miller and Youngquist"baseAuthorityYear="1948"class="Cephalopoda"family="Neoglyphioceratidae"genus="Pachylyroceras"kingdom="Animalia"pageId="20"pageNumber="101"phylum="Mollusca"rank="species"species="cloudi">
<collectingCountryid="F32C7638FC48FFB8FBBAFCBBFB6DFCF1"box="[1135,1188,846,869]"name="United States of America"pageId="20"pageNumber="101">USA</collectingCountry>
and equivalent age strata in
<collectingRegionid="49FFF84AFC48FFB8FC9AFC9BFC56FC11"box="[847,927,878,901]"country="United States of America"name="Nevada"pageId="20"pageNumber="101">Nevada</collectingRegion>
and
<collectingRegionid="49FFF84AFC48FFB8FC07FC9BFBC0FC11"box="[978,1033,878,901]"country="United States of America"name="Utah"pageId="20"pageNumber="101">Utah</collectingRegion>
