Chondrichthyan biofacies in the Late Famennian of Utah and Nevada

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CHONDRICHTHYAN BIOFACIES IN THE LATE FAMENNIAN OF UTAHAND NEVADAAuthor(s) MICHAŁ GINTERSource Journal of Vertebrate Paleontology 21(4)714-729 2001Published By The Society of Vertebrate PaleontologyDOI httpdxdoiorg1016710272-4634(2001)021[0714CBITLF]20CO2URL httpwwwbiooneorgdoifull1016710272-4634282001290215B07143ACBITLF5D20CO3B2

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714

Journal of Vertebrate Paleontology 21(4)714ndash729 December 2001q 2001 by the Society of Vertebrate Paleontology

CHONDRICHTHYAN BIOFACIES IN THE LATE FAMENNIAN OF UTAH AND NEVADA

MICHAŁ GINTERInstitute of Geology Warsaw University Zwirki i Wigury 93 02ndash089 Warszawa Poland

ABSTRACTmdashLate Famennian assemblages of chondrichthyan microremains especially teeth from Nevada and Utahrepresenting two zones of different water depth are analysed and compared to formerly described pelagic chondri-chthyan biofacies from the areas between S Euramerica and NW Gondwana The assemblage from the deeper (deepto moderately deep subtidal) zone is comparable to the Phoebodus-Thrinacodus biofacies but it lacks such typicalforms as Ph gothicus and Th tranquillus The assemblage from the shallower (shallow subtidal) zone might be anequivalent of the Protacrodus biofacies from which it differs in containing Th ferox and some other shallow watertaxa thus far unknown or very rarely found from the Famennian of central Europe and Africa New definitions ofchondrichthyan biofacies are proposed

INTRODUCTION

Four informal categories of the most common late Famen-nian chondrichthyans based on the gross morphology of teethcan be distinguished in the hitherto described collections ofshark microremains These are cladodonts ie sharks such assymmoriids stethacanthids or Cladoselache (Williams 1985)with teeth characterized by the largest relatively slender centralcusp sharks with tooth-crowns composed of thick and lowpartially or completely fused cusps such as Protacrodus(Gross 1973) phoebodontids (Phoebodus and Thrinacodus)with three delicate sigmoidal main cusps almost equal to eachother (Ginter and Ivanov 1992 Ginter 2000 Turner 1982)and Jalodus (5Phoebodus australiensis Long 1990) with thetooth-crown similar to that of the phoebodontids but with non-sigmoidal cusps ornamented on the labial side with coarseanastomosing cristae It seems that sharks belonging to theabove categories differ in their mode of life and feeding habits(see discussion in Ginter 2000) Cladodonts apparently used tohunt close to the water surface and therefore they could entermany different environments including shallow restricted ep-icratonic gulfs of the Main Devonian Field (Latvia and NWRussia Ivanov and Luksevics 1994) or the late FamennianCleveland Shale Basin an environment characterized by an an-oxic bottom water layer (Williams 1990) Protacrodonts prob-ably lived close to the bottom searching for attached or slowlymoving shelly prey and therefore they needed rather shallowwell oxygenated waters By analogy with a modern shark Chla-mydoselachus anguineus Garman 1884 it is possible to assumethat Phoebodus and Thrinacodus preyed on small fish like pa-laeoniscoids and unarmoured cephalopods They did not enterthe shallow waters of the Main Devonian Field and were veryrare (only a single species Ph politus Newberry 1889) in theCleveland Shale Basin This might suggest that Phoebodus andThrinacodus preferred open shelf environments and were insome way affected by the conditions at the bottom and abovewhich suggests in turn that they lived like Chlamydoselachusrather low in the water column It is difficult to determine themode of life of Jalodus As in the case of the phoebodontidsit is known only from teeth but whereas the phoebodont teethcan be compared to those of Chlamydoselachus the teeth ofJalodus are unlike those of any modern shark or a chondri-chthyan known from articulated skeletons Thus it can only besaid that it apparently represents open marine fauna (Ginter1999)

Recent investigation (Ginter 1999 2000) of pelagic chon-

drichthyan microremains from the late Famennian (Early ex-pansa through EarlyMiddle praesulcata conodont Zones) ofthe regions between the SE Euramerica and NW Gondwana(Fig 1A) showed that the relative abundances of the abovelisted chondrichthyan tooth categories differ in relation to depthandor distance from the land As a result of the study on richcollections mainly from Thuringia (Germany) Montagne Noire(France) Holy Cross Mountains (Poland) and East Anti-Atlas(Morocco) three general chondrichthyan biofacies were pro-posed (Ginter 2000)

1 The deep water Jalodus biofacies in which more than 25is composed of Jalodus teeth and the frequency of PhoebodusThrinacodus or Protacrodus is lower than that

2 The intermediate Phoebodus-Thrinacodus biofacies char-acteristic of moderately deep shelves with more than 25 ofthese two genera counted together

3 The shallow water Protacrodus biofacies with high fre-quency (more than 25) of the latter genus and lower frequen-cy of the other chondrichthyans mentioned above

The term lsquolsquochondrichthyan biofaciesrsquorsquo is understood here asa natural assemblage of chondrichthyan remains (usually onlyteeth) characteristic of a certain type of paleoenvironment TheJalodus biofacies was recorded from the Buschteich section inThuringia representing probably a low submarine rise sur-rounded by deep basinal environments situated far from con-tinental margins This biofacies is also known from Thailand(Long 1990) The Phoebodus-Thrinacodus biofacies occurs inmany carbonate shelf localities like Ostrowka (Holy CrossMountains) Soureille drsquoIzarne (Montagne Noire) or the SouthUrals The assemblage corresponding to the Protacrodus bio-facies was found from shallow water facies of the Tafilalt Plat-form Morocco

Biofacies definitions proposed by Ginter (2000) needed ver-ifying by comparison with some other precisely dated materialfrom a different region of the world Such an opportunity camewith the collection of ichthyoliths from the localities in westernUSA kindly loaned to me by Dr C A Sandberg (USGS Den-ver) Conodonts from these localities were used to create theLate Devonian Standard Conodont Zonation (Ziegler and Sand-berg 1984 1990) and the alternate shallow-water conodont zo-nation (Sandberg and Dreesen 1984) The compound studieson the Devonian of western USA the results of which werepresented by Sandberg et al (1988) were also partly based onthe same localities The present paper concerns only the lateFamennian part of that diverse and rich collection from an arealimited to the states of Utah and Nevada and two further lo-

715GINTERmdashFAMENNIAN CHONDRICHTHYAN BIOFACIES

FIGURE 1 A position of Utah and Nevada (U1N) and comparative regions on a simplified paleogeographic reconstruction of Euramerica andNW Gondwana in the late Famennian (after Scotese and McKerrow 1990 modified) Abbreviations P Holy Cross Mts Poland T ThuringianSlate Mts Germany F Montagne Noire France M Tafilalt Platform Morocco B paleobathymetric map of Utah and Nevada and adjacentstates in the Early expansa Zone (after Sandberg et al 1988 modified) Brick pattern to the east shows the extent of shallow water deposits ofthe Chaffee Group Circles indicate localities which yielded ichthyoliths For information on localities see Table 2

calities situated close to their borders The whole collection willbe presented in a separate study The main aims of this paperare the preliminary description of the new material especiallythat of chondrichthyan origin and to test to what extent if atall the chondrichthyan biofacies model elaborated for Europeand North Africa can be applied to the late Famennian of west-ern North America

PALEOGEOGRAPHIC FRAMEWORK

The area of western USA was covered in the Late Devonianby a vast epicratonic sea whose extent and depth depended onthe eustatic changes of global ocean level as well as on theregional and local block movements of the substrate The seawas bordered from the east by an elongated uplifted structurethe Transcontinental arch During the largest transgressionseg in the Early rhenana conodont Zone the Arch was splitby narrow straits connecting western regions with the seas onthe eastern side of the platform Sandberg et al (1988) pre-sented changes in the extent of the western sea and its depth inthe Late Devonian According to their model the territories ofNevada and Utah were divided into a generally shallower areato the south-east and a deeper area to the north-west In theexpansa Zones (Fig 1B) a large part of eastern Nevada and the

north-western part of Utah were occupied by a deep subtidallithofacies in the Early expansa represented mainly by blackshales with micrite concretions and subsequently by limestonesThe moderately deep lithofacies belt runs diagonally fromnorthern Utah through to south-eastern Nevada along the Se-vier thrust system and it is composed mainly of sandy carbon-ate rocks The deposits which belong to the latter lithofaciesprobably developed on a slope within the drowned carbonateplatform which was a dominant structure here during the mid-dle Frasnian Almost all Utah except for a small northwesternfragment belongs to the shallow subtidal lithofacies repre-sented by various carbonates for instance the Pinyon PeakLimestone which yielded the largest part of the late Famennianichthyolith collection

To the west of the areas studied in the late Famennian theedge of the continental crust and the oceanic basin extendedHowever because of strong tectonic deformations and transla-tion the distance from the open ocean to the carbonate platformcannot be determined precisely On the other side to the eastof Utah the very shallow subtidal to peritidal carbonates andshales of the Chaffee Group occur well recognized from theEast Glenwood Canyon section of Colorado The areas furtherto the east and towards the Transcontinental arch were occupiedby the peritidal lithofacies

716 JOURNAL OF VERTEBRATE PALEONTOLOGY VOL 21 NO 4 2001

In addition to lithologic data the range of bathymetric zonesis confirmed by the distribution of conodont biofacies (Sand-berg and Dreesen 1984) The deep and moderately deep sub-tidal lithofacies area roughly corresponds to the range of pal-matolepid-polygnathid biofacies (palmatolepid-bispathodid inthe deeper part) and diverse polygnathid-icriodid-pelekys-gnathid communities are characteristic of the shallow subtidalzone

MATERIAL

The ichthyoliths come from 26 late Famennian samples fromthe interval of the Early expansa through Middle praesulcataconodont Zones However the real time range may be shortereven as short as the Early through Late expansa Zones becauseprecise dating was not always possible Twenty four samplesyielded chondrichthyan teeth The samples are generally pooraltogether 90 shark teeth were found which means slightly lessthan four shark teeth per sample Moreover the richest sampleBCT-29 yielded 22 specimens so the average number in theother samples does not exceed three In addition to the teeth afew chondrichthyan scales also occur in the material as wellas about 20 parasymphysial struniiform teeth together withsome scales and conical teeth of actinopterygians The speci-mens are in most cases heavily broken and worn although sev-eral well preserved ones can be found Their color varies fromblack to light brown to amber to white even specimens fromthe same sample unlike conodont elements can have differentcolors This has also been shown for Pennsylvanian ichthyolithsfrom Oklahoma (Tway 1982) and seems to be a typical situa-tion

To the late Famennian assemblage a single slightly oldersample EGL-10 from the Late postera Zone of the shallowwater Chaffee Group of Colorado was added in order to illus-trate a characteristic nearshore fish assemblage The sampledoes not contain chondrichthyans but it yielded three lungfishtoothplates and several struniiform teeth The specimens arehoused at the Institute of Geology Warsaw University (abbre-viated as IGPUW) in Warsaw

SYSTEMATIC PALEONTOLOGY

Class CHONDRICHTHYES Huxley 1880Subclass ELASMOBRANCHII Bonaparte 1838

Order indetFamily PHOEBODONTIDAE Williams in Zangerl 1981

Genus PHOEBODUS St John and Worthen 1875

Type Species Phoebodus sophiae St John and Worthen1875

PHOEBODUS LIMPIDUS Ginter 1990(Fig 2FndashK)

Phoebodus sp Wang and Turner 1985225 pl 2 fig 3a bPhoebodus limpidus Ginter 199075ndash76 pl 4 figs 2ndash5 [non

fig 6a b 5 Ph fastigatus]Phoebodus cf limpidus Ginter Wang and Turner 199565 pl

8 fig 2Phoebodus limpidus Ginter Ginter and Ivanov 1995pl 1 figs

9 10Phoebodus limpidus Ginter Ginter 1995fig 4FPhoebodus limpidus Ginter Turner in Xia 199798 pl 26 figs

8 14 16Phoebodus sp A Lelievre and Derycke 1998301ndash302 fig

4AndashCPhoebodus limpidus Ginter Ginter 199932 pl 2 figs 1ndash3Phoebodus limpidus Ginter Ginter and Ivanov 2000328 pl

2F

Phoebodus limpidus Ginter Ginter 2000371ndash373 figs 4E F5BndashD 6AndashC

Referred Specimens Nineteen specimens IGPUWPs34IGPUWPs35 and IGPUWPs331ndash47 from sample BCT-29Late expansa or Early praesulcata Zones Nevada two speci-mens IGPUWPs348 and 49 from sample SPH-1 Late ex-pansa or Early praesulcata Zones Utah two specimens IG-PUWPs33 and 50 from sample CAU-5A Early expansaZone Utah three specimens IGPUWPs351ndash53 from sampleS-312C Middle or Late expansa Zone Wyoming two speci-mens IGPUWPs389 and 90 from sample CCC-21 Early ex-pansa Zone Utah For details see Table 1

Distribution Late Devonian late Famennian Early expan-sa through EarlyMiddle praesulcata Zones South China Xin-jiang South Urals Holy Cross Mts (Poland) Montagne Noire(France) Western USA Ginter (2000table 1) gives a reviewof Ph limpidus occurrences

Description Specimens generally conform with the diag-nosis given by Ginter (1990) They have triangular bases nar-rowing lingually (but compare Fig 2F) with a thin and elon-gated labio-basal projection and a broad and vague apical but-ton corresponding to that The cusps are usually strongly di-vergent mesio-distally (Fig 2G) The teeth are broken or at leastheavily abraded so the cristae on the labial side of the cuspsalways very gentle here can be seen only in bigger specimens(Fig 2J K) The intermediate cusplets are relatively long par-ticularly in the smaller teeth (Fig 2H) The size differencesbetween the specimens is considerable the distance from thelabio-mesial to the labio-distal angles reaches from 04 to 12mm

PHOEBODUS cf GOTHICUS Ginter 1990(Fig 3A B)

Referred Specimens One specimen IGPUWPs36 fromsample PIN-3 and one specimen IGPUWPs354 from samplePIN-9 Early expansa Zone Utah For details see Table 1

Description The base of the tooth from PIN-3 (Fig 3A B)is strongly abraded and all the cusps are broken However it isvisible that the tooth was relatively large (about 2 mm alongthe crown) the base was extended far lingually the apical but-ton was large and distinct the single large main basal canalwent from the lingual side of the base towards the crown Thecrown was composed of three probably almost equal maincusps curved lingually and two intermediate smaller cuspletsThe cusps were covered with strong cristae on the labial sideand the ornamentation was much more gentle on their lingualside

A second specimen from PIN-9 is only a half a tooth withbasal parts of two strongly cristated main cusps and of an in-termediate cusplet The lingual part of the base is lost but alarge portion of a prominent button is visible

Discussion The characters of both specimens strongly sug-gest that they belong to Ph gothicus However because of thelack of the most diagnostic lingual part of the base it is thoughtbetter to leave them in open taxonomy

Genus THRINACODUS St John and Worthen 1875

Type Species Diplodus incurvus Newberry and Worthen1866

THRINACODUS FEROX (Turner 1982)(Figs 3CndashE 4AndashC)

Harpago ferox Turner 1982118ndash123 figs 2ndash4Harpagodens ferox (Turner) Turner 198338Harpagodens ferox (Turner) Wang and Turner 1985266ndash227

pl 2 figs 11ndash12


FIGURE 2 AndashE Stethacanthus sp sample CAU-5A AndashD IGPUWPs31 lateral occlusal labial and lingual views E IGPUWPs32 labialview FndashK Phoebodus limpidus F G IGPUWPs33 sample CAU-5A basal and labial views H I IGPUWPs34 sample BCT-29 occlusaland labial views J K IGPUWPs35 sample BCT-29 labial and occlusal views Scale bar equals 05 mm

Harpagodens ferox (Turner) Wang 1989105ndash106 pl 28 figs6ndash7 pl 29 fig 2a b pl 30 figs 1ndash4

non Thrinacodus ferox Turner [sic] Long 199061ndash62 fig 5IndashMnon Thrinacodus ferox (Turner) Ginter 199076 pl 3 figs 2ndash

4 5 Th tranquillusThrinacodus (Harpagodens) ferox (Turner) Turner 1991 fig

6 pl 2 fig Gcf Thrinacodus ferox (Turner) Kietzke and Lucas 199218

fig 2DndashHnon Thrinacodus ferox (Turner) Derycke 199230 pl 1 fig

3 5 Th tranquillus

Thrinacodus ferox (Turner) Turner 1993 fig 87 Fcf Thrinacodus ferox (Turner) Duffin 19932 pl 1ndash2Thrinacodus ferox (Turner) Derycke et al 1995472 pl 3 fig

B pl 4 fig AThrinacodus ferox Turner [sic] Ginter 1995 fig 5A BThrinacodus sp Ivanov 1996 fig 4A B E [cf fig 4D non

fig 4C 5 Th tranquillus]Thrinacodus ferox Turner [sic] Ginter and Ivanov 1996267ndash

269 fig 2CndashD [non fig 2A B 5 Th tranquillus]Thrinacodus sp Ginter 199934 pl 3 figs 6 7 [non figs 1ndash

5]


TABLE 1 Distribution of ichthyoliths and frequency of chondrichthyan teeth in the late Famennian of western USA For the information onlocalities see Table 2 Sandberg et al (1988) and Stevens et al (1996)


TABLE 2 List of localities in Utah Nevada and adjacent states which yielded late Famennian chondrichthyan teeth

Initials Locality Physiographic setting County State

BCS Broad Canyon Stansbury Island Tooele UtahBLN Blawn Mountain Wah Wah Mountains Beaver UtahBRD Broad Canyon Stansbury Mountains Tooele UtahCAU Causey Reservoir Wasatch Range Weber UtahCCC City Creek Canyon Wasatch Mountains Davis-Salt Lake UtahMWZ Mowitza Mine Star Range Beaver UtahPIN Pinyon Peak East Tintic Mountains Utah UtahSPH Spring Hollow Bear River Range Cache UtahBCT Bactrian Mountain Pahranagat Range Lincoln NevadaLIM Lime Mountain Tule Desert Lincoln NevadaLBG Lost Burro Gap Cottonwood Mountains Inyo CaliforniaS-312C Shoshone Canyon Absaroka Range Park Wyoming

FIGURE 3 A B Phoebodus cf gothicus IGPUWPs36 sample PIN-3 occlusal and lateral views CndashE Thrinacodus ferox C IGPUWPs37 sample PIN-3 occlusal view D IGPUWPs38 sample LBG-3 lateral view E IGPUWPs39 sample CCC-F1 lateral view Scale barequals 05 mm

Thrinacodus sp Ivanov 1999273 pl 4 figs 2 4Thrinacodus sp Ginter and Ivanov 2000330 pl 2 fig H [non

fig G 5 Th tranquillus]

Referred Specimens One specimen IGPUWPs355 fromsample BCS-2 unknown position within the former costatusZone (Middle expansa through Middle praesulcata Zones)Utah two specimens IGPUWPs356 and 57 from sampleCCC-21 Early expansa Zone three specimens IGPUWPs39 10 and 58 from sample CCC-F1 Middle or Late expansaZones Utah One specimen IGPUWPs37 from sample PIN-3 Early expansa Zone Utah Two specimens IGPUWPs359and 60 from sample BLN-5 Early expansa Zone Utah Onespecimen IGPUWPs38 from sample LBG-3 Middle expan-sa Zone California For details see Table 1

Distribution Late Devonian late Famennian (Early expan-sa Zone) through Early Carboniferous Serpukhovian (nodosus

Zone) Queensland Western Australia and New South Wales(Australia) South China South Urals Novaya Zemlya andMoscow Region (Russia) Holy Cross Mts and Cracow Upland(Poland) Montagne Noire (France) Derbyshire (England)Western USA

Description The material from Western USA contains thewhole range of Th ferox tooth morphotypes from extremelyasymmetrical with a long base the main basal canal openingsituated at the middle of the base one lateral cusp very welldeveloped and the other cusps highly reduced and placed almostparallel to the side of the base (Fig 3D E) to less asymmetricalforms with all the cusps apparently functional and the base stilllong and flattened at the end (Fig 3C these forms are the mostsimilar to Th tranquillus Ginter 2000) to small specimens withall the cusps short and almost equal and the base very short (Fig4AndashC) All morphotypes have their lsquolsquomirrorrsquorsquo equivalents (com-


FIGURE 4 AndashC Thrinacodus ferox parasymphysial tooth IGPUWPs310 sample CCC-F1 lateral occlusal and labial views D Bransonellasp IGPUWPs311 sample CCC-F1 labial-basal view EndashG lsquolsquoOrodusrsquorsquo sp IGPUWPs312 sample PIN-9 lateral lingual and occlusal viewScale bar equals 05 mm

pare Fig 3D and E) The ratio between the number of specimenswith asymmetrical crowns and the number of sub-symmetricalspecimens is 82 This is comparable to ratios observed fromother collections (usually about 101) According to the hypo-thetical reconstruction of a Thrinacodus jaw by Turner (1982fig5) the teeth with asymmetrical crowns come from lateral branch-es of a jaw and those with symmetrical crowns from the sym-physial tooth family Because of the slight asymmetry of the basein the latter specimens it seems more likely that they form twoparasymphysial tooth rows rather than a single symphysial one(which is probably the case in Th tranquillus)

Discussion In the paper on chondrichthyans from Thurin-gia Ginter (199934) wrote that lsquolsquotypical asymmetrical forms[of Thrinacodus] with one lateral cusp much larger than theothers [5Th ferox] are the most common in the upper part ofthe Buschteich profile (from the sample Bu-19 Middle expansaZone upwards)rsquorsquo However it no longer seems to be true there-examination of Thuringian material shows that all thrinaco-donts from that sample and up to the end of the Famennian ofthe Buschteich section clearly fall within the variation of Thtranquillus and none belongs to Th ferox The oldest undoubtedspecimen of the latter species from that region was found fromthe Late praesulcata Zone of the nearby Kahlleite East sectionIn Buschteich Th ferox appears in Tournaisian sulcata ZoneThis being the case it seems that Th ferox was virtually un-known from the Famennian of Europe or elsewhere before theLate praesulcata Zone as far as published records are con-cerned (with exception of a short note in Ginter 1995 on asingle sample from the South Urals) All Thrinacodus findsfrom before that zone (eg Ginter 1990 Derycke 1992) ap-parently correspond to Th tranquillus The material from theWestern USA is the first evidence of the occurrence of Th feroxas early as the Early expansa Zone

There are several places in the world in which similar to thecase described from Thuringia Th ferox replaced Th tran-quillus by the end of the Devonian which probably was a resultof the Hangenberg Event and the subsequent shallowing inmany pelagic areas (Ginter 1995) The most spectacular andprecisely controlled was the replacement in the La Serre area(Montagne Noire France) A rich sample from the Middle orLate expansa Zone from the Soureille drsquoIzarne contains onlyTh tranquillus (20 specimens Ginter 2000) but the lowermostCarboniferous sulcata Zone of the nearby La Serre sectionyielded only Th ferox (Derycke et al 1995) This does notnecessarily mean although it is possible that Th tranquilluswas extinct by that time but it is clear that the change of en-vironmental conditions was favorable to its younger relative

Order XENACANTHIFORMES Berg 1940Family indet

Genus BRANSONELLA Harlton 1933

Type Species Bransonella tridentata Harlton 1933

BRANSONELLA sp(Fig 4D)

Referred Specimen One specimen IGPUWPs311 fromsample CCC-F1 Middle or Late expansa Zone Utah For de-tails see Table 1

Description The tooth and particularly its lingual part isbadly damaged However it is assumed that the base was sub-circular and somewhat elongated labio-lingually The labio-bas-al projection is probably arcuate in phoebodont style The cuspsare relatively short almost straight (non-sigmoidal) the lateralcusps only slightly diverging from the median cusp (no morethan 30 degrees) The ornamentation of the labial side consists


FIGURE 5 AndashC Protacrodus sp B IGPUWPs313 sample PIN-3 labial occlusal and lingual views D E lsquolsquoSymmoriumrsquorsquo sp IGPUWPs314 sample BCT-29 basal and labial views Scale bar equals 05 mm

of four subparallel cristae running separately from the base tothe tip The cusps are probably slightly labio-lingually com-pressed but this cannot be proved because of the lack of thelingual part This is also the reason that the presence or char-acter of a button cannot be determined

Discussion By its general features the specimen resemblesthe teeth of Bransonella but also those of Jalodus Ginter 1999It differs from the latter genus by the small angle between thecusps and from both by the different ornamentation type inthe representatives of these genera pairs of cristae join at dif-ferent heights which gives the specific lsquolsquolanceolatersquorsquo sculptureof the labial side The only published specimen of Bransonellawhich displays all the characteristics similar to the tooth underdescription is Bransonella sp from the DevonianndashCarbonifer-ous boundary beds of the Timano-Pechora Province (Russia)presented by Ivanov (1999277ndash278 pl 4 fig 1) That speci-men has a wide and indistinct button which makes it closer toJalodus but otherwise it more resembles Bransonella Becauseof the combination of characters and age of the tooth Ivanov(1999) suggested that it was a representative of the genus Bran-sonella occupying the intermediate position between Phoebod-us [5Jalodus] australiensis and typical Bransonella speciesThe same statement also can be applied to the specimen fromUtah Similarities between the teeth of Bransonella and Jalodushave been noted before (Ginter and Ivanov 1996 Ivanov andGinter 1996) and the occurrence of such intermediate formslike Bransonella sp might suggest phylogenetic relationshipsbetween these two genera However any further discussion onthat subject has to wait until more number of better preservedspecimens of Bransonella sp type are found

Order SYMMORIIFORMES Zangerl 1981Family SYMMORIIDAE Dean 1909

Genus SYMMORIUM Cope 1893

Discussion For more than 15 years many authors (eg Zi-dek 1992) following Williamsrsquo (1985) publication have as-

cribed certain isolated very characteristic teeth to the genusSymmorium and usually to S reniforme Cope 1893 Thosealleged Symmorium teeth formerly referred to as Cladodus(Leidy 1873 and many others) or Ctenacanthus (Glikman1964) commonly occur in the Famennian and particularly inthe Carboniferous worldwide They have lingually directed ba-ses cladodont-type crowns ie with a central cusp much lon-ger than the lateral ones and two widely separated buttonscorresponding to two labio-basal projections There is a con-cavity in the middle of the labial side of the base between theprojections and in the labio-basal part of the median cuspHowever the tentative identification proposed by Williams(1985) does not seem to be justified The teeth of the holotypefor the genus Symmorium reniforme Cope 1893 (Field Mu-seum of Natural History Chicago specimen UF 574) haveneither two buttons nor two distinct labio-basal projections (cfWilliams 1985text-fig 162) This taxonomic problem stillneeds a thorough study of collections and literature and there-fore until it is finally resolved I temporarily retain the namelsquolsquoSymmoriumrsquorsquo in inverted commas to the teeth characterizedby the features listed above

lsquolsquoSYMMORIUMrsquorsquo sp(Fig 5D E)

Referred Specimens One specimen IGPUWPs314 fromsample BCT-29 Late expansa or Early praesulcata Zones Ne-vada one specimen IGPUWPs361 from sample SPH-1 Lateexpansa or Early praesulcata Zones Utah two specimens IG-PUWPs362 and 63 from sample CAU-5A Early expansaZone Utah one specimen IGPUWPs364 from sample S-312C Middle or Late expansa Zone Wyoming one specimenIGPUWPs365 from sample LIM-1 Early expansa Zone Fordetails see Table 1

Description Most specimens of lsquolsquoSymmoriumrsquorsquo sp havelaterally elongated bases (about 1ndash15 mm mesio-distally) withtwo distinct labio-basal projections and a shallow depression


between them The projections are semi-elliptical and their bas-al faces are flat The two apical buttons are rather weak Al-though the specimens are abraded they display remains ofstrong cristae on the labial side of the cusps The single spec-imen from SPH-1 is smaller than the others bearing no orna-mentation on the cusps with sharp triangular labio-basal pro-jections

Discussion The state of preservation of the larger speci-mens does not allow any closer comparison with other knowncladodont sharks However the smallest tooth with hook-likelabio-basal projections resembles to some extent lsquolsquoSymmoriumrsquorsquoglabrum described from the Famennian of Europe (ThuringiaMontagne Noire Holy Cross Mountains) by Ginter (19992000) and from Thailand by Long (1990) It is also possiblethat smaller teeth could have belonged to juvenile individualsthe teeth of which generally had weaker ornamentation and thatthe form of the labio-basal projections could change with thesize of a tooth

Family STETHACANTHIDAE Lund 1974Genus STETHACANTHUS Newberry 1889

Type Species Physonemus altonensis St John and Wor-then 1875

STETHACANTHUS sp(Fig 2AndashE)

Referred Specimens Four specimens from sample CAU-5A IGPUWPs31 2 66 67 Early expansa Zone one spec-imen IGPUWPs368 from sample BCS-3 unknown positionwithin the former costatus Zone (Middle expansa through Mid-dle praesulcata Zones) one specimen IGPUWPs369 fromsample CCC-21 Early expansa Zone one specimen IGPUWPs370 from sample PIN-3 Early expansa Zone all samplesfrom Utah For details see Table 1

Description Small cladodont teeth usually no more than07 mm along the crown with triangular or trapezoidal bases(Fig 2B) extending far and narrowing lingually The button isdouble in the shape of horizontal eight (Fig 2D) and some-times the connection between the two parts is lost The labio-basal projection is single very narrow (usually narrower thanthe foot of the median cusp) narrowing and decreasing inheight lingually When in a tooth family the projection prob-ably fits in the valley between the button and the crown andprobably also between the two parts of the button of the un-derlying tooth The crown is composed of five recurved cusps(Fig 2C E) the median cusp is the highest and the outer pairof lateral cusps is higher than the intermediate ones All thecusps are slender subcircular in section and bear the typicalstethacanthid ornamentation of long subparallel cristae run-ning from the base to the tip on both sides of a cusp

Discussion This species displays several features charac-teristic of certain stethacanthids such as S thomasi (Turner1982) ie the button has a figure eight shape and a single welldeveloped labio-basal projection as well as the general formand ornamentation of the crown However several tendenciesmake it also close to Denaea (eg D meccaensis Williams1985) long lingual extension and in some cases trapezoidaloutline of the base the medial groove between the two parts ofthe button occurring in some specimens and slender cuspsThis suggests that Stethacanthus sp might occupy an interme-diate position between typical broad based stethacanthids andlate denaeids and could be close to the early forms of the lattergroup such as D fournieri (Pruvost in Fournier and Pruvost1922) teeth of which are not yet sufficiently characterized

Cohort EUSELACHII Hay 1902Superfamily PROTACRODONTOIDEA Zangerl 1981

Family PROTACRODONTIDAE Zangerl 1981Genus PROTACRODUS Jaekel 1921

Type Species Protacrodus vetustus Jaekel 1921

PROTACRODUS aff VETUSTUS Jaekel 1921(Fig 6AndashC)

Referred Specimens Two specimens IGPUWPs316 and71 from sample MWZ-1A2 one specimen IGPUWPs372from sample MWZ-3A two specimens IGPUWPs373 74from sample LIM-1 two specimens IGPUWPs375 76 fromsample PIN-9 one specimen IGPUWPs315 from samplePIN-3 all from the Early expansa Zone Utah one specimenIGPUWPs377 from sample BCS-2C Late expansa or Earlypraesulcata Zone Utah one dubious specimen IGPUWPs378 from sample BCT-29 Late expansa or Early praesulcataZone Nevada For details see Table 1

Description The tooth crown is composed of a thick py-ramidal median cusp and three pairs of much smaller similarlyshaped lateral cusps The angle between the median cusp andthe lateral ones increases laterally The second pair is somewhathigher than the other lateral cusps All the cusps are ornamentedwith distinct cristae joining at the tips (Fig 5C) The base iswide slightly extended lingually with an elongated concavityin its underside A regular row of pores opens on the lingual-apical side of the base along the crown similarly organizedpores occur on the labio-basal rim and in the basal concavity

Discussion The specimens clearly resemble P vetustusteeth from Bad Wildungen in Germany (Gross 1938) the onlydifference is the much higher median cusp in relation to thelateral ones in the American material For that reason theseforms are placed in the open taxonomy

PROTACRODUS sp A(Fig 6D E)

Referred Specimens Two specimens IGPUWPs317 and79 from sample MWZ-1A2 one specimen IGPUWPs380from sample CAU-5A all from the Early expansa Zone Utaha single broken tooth IGPUWPs381 from sample SOL-3Middle or Late expansa Zone Utah For details see Table 1

Description Protacrodont teeth with largely fused lateralcusps it is possible to distinguish the tips of the cusps closestto the median cusp but the cusps of the two lateralmost pairsform together a strongly cristated ridge slightly curved inwardA distinct blade connecting the cusps runs all the way from themesial towards the distal side of a tooth The lingual extensionof the base is very short in the specimens from MWZ-1A2 itis missing

Discussion Similar protacrodont teeth with partly fusedcusps were presented by Gross (1973pl 35 fig 3) Their mor-phology suggests that they belong to some chondrichthyans in-termediate between typical protacrodonts and orodonts

PROTACRODUS sp B(Fig 5AndashC)

Referred Specimen One specimen IGPUWPs313 fromsample PIN-3 Early expansa Zone Utah For details see Table 1

Description A tooth with a prominent median cusp some-what inclined lingually and the lateral cusps fused to form anarrow but distinctly cristated ridge It is possible to distinguishthe tips of the most lateral cusps which strongly diverge (atabout 45 degrees) from the median cusp The base has a shortlingual extension two symmetrically placed horizontal canalsperforate the base from its lingual to the labial side Because theunderside is abraded the canals are observed partly as grooves


FIGURE 6 AndashC Protacrodus aff vetustus A B IGPUWPs315 sample PIN-3 lingual and occlusal views C IGPUWPs316 sampleMWZ-1A2 basal view D E Protacrodus sp A IGPUWPs317 sample MWZ-1A2 lingual and occlusal views F G lsquolsquoOrodusrsquorsquo sp IGPUWPs318 sample PIN-3 occlusal and labial views H lsquolsquoOrodusrsquorsquo sp IGPUWPs319 lingual-occlusal view Scale bar equals 05 mm

Discussion The tooth differs greatly from all known pro-tacrodonts because of its fused cusps Nevertheless the formof the base and the ornamentation of the crown make it is closerto Protacrodus than to any other Devonian chondrichthyan ge-nus The most similar Carboniferous chondrichthyan teeth be-long to the genus Mesodmodus However the specimens of Mexculptus (St John and Worthen 1875pl 5 figs 18 19 2122) are much more elongated mesio-distally and asymmetricalMesodmodus sp from the late Tournaisian of the South Urals

(Ivanov 1996fig 7E F) displays a labial depression under themedian cusp

Order ORODONTIFORMES Zangerl 1981Family ORODONTIDAE De Koninck 1878

Genus ORODUS Agassiz 1838

Discussion So called orodont teeth are mesio-distally elon-gated crushing teeth generally similar to protacrodonts from


FIGURE 7 Sarcopterygian microremains AndashC Andreyevichthys sptoothplates of a juvenile specimen IGPUWPs320 sample EGL-10A B prearticular toothplate labial and occlusal views C entoptery-goid toothplate occlusal view D E Strunius rolandi teeth of a par-asymphysial tooth-whorl IGPUWPs321 sample PIN-8A Scale barequals 05 mm

which they differ by further fusion of the cusps and gradualreplacement of orthodentine with osteodentine and tubular den-tine (Lebedev and Vrsquoyushkova 1993) The base usually has ashort lingual extension and the crown retains strong cristationJudging only from tooth morphology it is difficult to distinguishtrue orodonts from representatives of other chondrichthyanswith similar feeding habits (eg eugeneodontids) so the formsdescribed below are only tentatively referred to Orodus ss

lsquolsquoORODUSrsquorsquo spp(Figs 4EndashG 6FndashH)

Referred Specimens One specimen IGPUWPs319 fromsample CAU-5A Early expansa Zone one specimen IGPUWPs382 from sample SOL-3 Middle or Late expansa Zoneone specimen IGPUWPs318 from sample PIN-3 Early ex-pansa Zone three specimens IGPUWPs383ndash85 from samplePIN-8A and three IGPUWPs312 86 87 from sample PIN-9 Early expansa Zone one specimen IGPUWPs388 fromsample BCS-2C Late expansa or Early praesulcata Zones allsamples from Utah For details see Table 1

Description There are three orodont tooth types in the ma-terial The first has three incompletely fused cusps in the crownsubcircular in occlusal view (Fig 6F G) The median cusp islarge more than 05 mm in diameter and the lateral cusps arethree times smaller All the cusps have smooth occlusal surfac-es possibly because of wear and subparallel vertical cristae onthe lingual and labial sides

The second tooth type is represented by a single fragmentaryspecimen (Fig 6H) Its base is almost vertical and perforatedby several canal openings Both faces of the crown are coveredwith distinct subparallel sometimes anastomosing vertical cris-tae A distinct groove runs along the crown-base interface

The third type (Fig 4EndashG) is the most unusual although themost frequent The teeth are elongated mesio-distally with avertical base depressed crownndashbase interface and a peculiarcrown composed of a mesio-distal main ridge and usually fivedistinct transverse vertical ridges on each side The upper endsof transverse ridges do not reach the height of the main ridgeUsually the space between two ridges corresponds to a ridgeon the other side This gives an oak-leaf occlusal shape to thecrown

Discussion The first tooth type is very similar to and prob-ably conspecific with that of Protacrodus sp indet from themiddle Famennian Maple Mill Shale of Iowa (Gross 1973pl35 fig 6) The only difference is a slightly higher median cuspand better preserved base in the latter specimen The second isthe most typical for orodonts and it also resembles crushinglateral teeth of certain hybodonts such as Hamiltonichthys ma-pesi (Maisey 1989figs 24ndash27) The third tooth type cannot bedirectly referred to any of known forms It might belong to anorodontid but it might also belong to a hybodontid or even aneoselachian

Class OSTEICHTHYES Huxley 1880Subclass SARCOPTERYGII Romer 1955

Order ONYCHODONTIFORMES Andrews 1973Family ONYCHODONTIDAE Woodward 1891

Genus STRUNIUS Jessen 1966

Type Species Strunius walteri Jessen 1966

STRUNIUS ROLANDI (Gross 1936)(Fig 7D E)

Referred Specimens Specimens from samples PIN-8APIN-10 LIM-1 BRD-2 BLN-4 BLN-5 and MWZ-2 Earlyexpansa Zone Utah (for details see Table 1) and from sampleEGL-10 Late postera Zone Parting Formation Chaffee Group

East Glenwood Canyon of Colorado River Eagle-GarfieldCounty Colorado

Distribution Early Frasnian (Late falsiovalis Zone)through late Famennian (Early or Middle expansa Zone) SouthUrals Central Devonian Field (Russia Ginter and Ivanov1995 Lebedev 1995) Latvia (Gross 1956) Holy Cross Mts(Poland Ginter 1995) Moravia (Ginter 1991) Germany (Jes-sen 1966) Western USA

Description Struniiform dentition consists of two tooth


types minute isolated conical teeth from the lateral parts ofjaws (these teeth are hard to distinguish from the teeth of otherosteichthyans) and two parasymphysial tooth-whorls with largeteeth the shape of which is diagnostic for each species Theidentification of S rolandi was based here on such parasym-physial teeth

Strunius rolandi toothwhorls are composed of a verticallycurved bony base and a few teeth with a large sigmoidal maincusp (2ndash5 mm) and an accessory small cusplets on each sideThe main cusp has a long pulp cavity the surface of the cuspis covered with numerous gentle ridges composed of second-ary chevron ornamentation (compare Lebedev 1995pl 1 fig4b) Most teeth found were separated from the bony base buta few specimens still retain fragments of bone at their basalpart (Fig 7D E)

Order DIPNOI Muller 1846Family CHIRODIPTERIDAE Campbell and Barwick 1990

Genus ANDREYEVICHTHYS Krupina 1987

Type Species Andreyevichthys epitomus Krupina 1987

ANDREYEVICHTHYS sp(Fig 7AndashC)

Referred Specimens Three toothplates of a single speci-men (IGPUWPs320) from sample EGL-10 Late posteraZone Parting Formation Chaffee Group East Glenwood Can-yon of Colorado River Eagle-Garfield County Colorado

Description One of the toothplates (Fig 7A B) is com-posed of five rows of separate tubercles smaller and closelyplaced lingually and gradually growing anteriorly and labiallythere are from four to seven tubercles in a row The toothplateis developed on an elongated piece of longitudinally foldedbone about 3 mm long The other two toothplates (Fig 7C) arerhombic and consist of five main rows of tubercles organizedsimilarly to those described above They are accompanied byone or two additional less prominent tubercles situated pos-teriorly

Discussion The first of the described elements is very prob-ably the right prearticular toothplate of a juvenile chirodipteridlungfish It is very similar to the specimen of Andreyevichthysepitomus from the late Famennian locality of Andreyevka Tularegion central Russia illustrated by Krupina (1995fig 5A)The specimen from Andreyevka apparently comprises the samepart of prearticular bone However it is only about 17 mm longand there are only four rows of tubercles It seems thereforethat it belonged to a somewhat younger individual (early larvalstage according to Krupina 1995) than that described here

The other two plates from EGL-10 might be entopterygoidtoothplates of the same individual as the first one They slightlyresemble the toothplate of A epitomus presented by Krupina(1995fig 5B) the additional tubercle(s) might correspond tothe lsquolsquoprimary cusprsquorsquo visible in the Russian specimen

Although very similar the toothplates do not necessary be-long to Andreyevichthys They also are comparable to juvenilespecimens of other dipnoans such as Chirodipteridae gen etsp nov (Jones and Turner 2000figs 5 6A) and Chirodipteruspotteri (Kemp 2000fig 2C) from the possible early- to mid-Famennian Coffee Hill Member of New South Wales or toSagenodus cf S periprion from the late Pennsylvanian Du-quesne limestone of Pennsylvania (Kemp 1998fig 4E F)However the material presented here seems to be the closest tothat from Andreyevka (see also Krupina and Reisz 1999) asfar as morphology and age are concerned so I propose in thispreliminary description to assign all three specimens from Col-orado to Andreyevichthys sp

DISTRIBUTION OF ICHTHYOFAUNA

Localities which yielded chondrichthyan microremains oc-cupy a narrow belt extending SWndashNE from the Nevada-Cali-fornia borderland to the northern part of Utah and western Wy-oming along the slope of the drowned carbonate platform Forthe purpose of this paper the localities were divided into twogroups according to their presumed depth in the late Famen-nian The first group represents deep and moderately deep sub-tidal lithofacies (the term lsquolsquodeeper zonersquorsquo corresponding tolsquolsquoslopersquorsquo of Sandberg and Dreesen (1984) will be used for thisarea) and the second group includes sections representing shal-low subtidal lithofacies (here called lsquolsquoshallower zonersquorsquo and cor-responding to lsquolsquoshelfrsquorsquo of Sandberg and Dreesen 1984) Onlyfour samples with 40 shark teeth come from the deeper zoneand 22 samples with 50 specimens represent the shallowerzone

In order to compare average taxonomic compositions of thesamples some taxa were grouped in informal categories similarto those used by Ginter (2000 see Introduction) based on themorphology of teeth and assumed modes of life and feedinghabits The genera Phoebodus and Thrinacodus were treatedseparately here but all protacrodont and orodont-like crushingteeth were counted and analyzed as a single group Similarlyall teeth with cladodont crowns together with Stethacanthusand lsquolsquoSymmoriumrsquorsquo were considered jointly Such grouping notonly made possible the comparison between the assemblagescharacteristic of the shallower and deeper zones but also helpedin comparison and correlation of the regional results with thosefrom elsewhere

Comparison of the two bathymetric zones revealed substan-tial differences in taxonomic compositions of chondrichthyanassemblages (Table 1 Fig 8) Phoebodus (in fact Ph limpidusonly) predominates in the deeper zone (64) protacro-donts1orodonts reach no more than 8 (one protacrodont-looking form which could also be a worn cladodont one Pro-tacrodus sp A and a single orodont tooth) whereas Thrina-codus is totally absent On the other hand Thrinacodus is quiteabundant in the shallower zone (20) and the frequency ofprotacrodonts1orodonts is reasonably high (44 with 20 oforodonts) in contrast to the poor representation of Phoebodus(8 actually only four specimens) Relative abundances of cla-dodonts are almost equal in the deeper and shallower zones(28 and 26 respectively) Only one specimen of Branso-nella was found from Utah and Nevada

Differences between the ichthyofauna from the shallower andthe deeper zones are emphasized by the distribution of sarcop-terygian remains Characteristic teeth of the onychodont Strun-ius rolandi are present and very common only in the samplesfrom the shallower zone and totally absent from the deeperzone Judging from the taxonomic composition of the sampleEGL-10 (12 S rolandi teeth three toothplates of a dipnoanAndreyevichthys sp no chondrichthyans) representing shallowsubtidal to peritidal environment of the slightly older Late pos-tera Zone sarcopterygians were even more abundant and di-versified closer to the shore

DISCUSSION

Correlation with the Other Regions

In the light of recent reports from the late Famennian ofEurope it is particularly surprising that the paleogeographic andpaleobathymetric ranges of Phoebodus and Thrinacodus are vir-tually separate in the western USA While in the seas of south-eastern Euramerica representatives of these two genera pre-ferred moderately deep shelf conditions which led to erectionof the Phoebodus-Thrinacodus biofacies (Ginter 2000) here inthe west Thrinacodus clearly appears to be a shallow water


FIGURE 8 Comparison of late Famennian chondrichthyan assemblages from the deeper and shallower zones of western USA The singlespecimen of Bransonella sp omitted

shark Explanation of this seems to be easy when we changethe observation level from genera to species While on theshelves between Euramerica and Gondwana the older speciesof Thrinacodus Th tranquillus was the dominant (if not theonly) representative of the genus in Nevada and Utah only theyounger species Th ferox was found Thus in spite of a ratherminor difference in tooth morphology (advanced crown asym-metry in Th ferox) there must have been substantial differencesin biogeographic ranges of these two species and probably alsoin their environmental preferences If these data are confirmedfrom elsewhere it would be the first evidence of intragenericenvironmental differentiation among Devonian sharks Thrina-codus ferox was very common in Early Carboniferous seas allover the world whereas it seems certain with some reserva-tions that Th tranquillus did not persist into the TournaisianMost of the Tournaisian through Serpukhovian records of Thferox come from shallow epicratonic facies such as the Kilbri-de Formation in Ireland (Duncan 1999) the oolitic facies ofLa Serre Montagne Noire (Derycke et al 1995) or limestonesfrom Kalinovskiye Vyselki in the Moscow region (Ginter andIvanov 1996) similar to that of the shallower zone of Nevadaand Utah and certainly different from open shelves of the lateFamennian of Europe and North Africa This partly explainswhy Th ferox is absent from the latter regions However the

question why it is absent even from shallow water facies of theTafilalt Platform (Morocco) and why Th tranquillus is absentfrom Nevada and Utah even from the deeper zone requiresfurther study Perhaps there are still too few samples from thedeeper zone to positively answer the question

Different environmental preferences of the two Thrinacodusspecies present difficulties in direct correlation of chondri-chthyan assemblages from Nevada and Utah with Europeanchondrichthyan biofacies In the shallower zone of Utah thefrequency of phoebodontids (Phoebodus1Thrinacodus) is high(above 25) which according to the definition given by Ginter(2000 see also Introduction herein) should indicate the Phoe-bodus-Thrinacodus biofacies corresponding to moderatelydeep shelf conditions However this would contradict the otherevidence such as lithology and conodont biofacies Of courseas discussed above Th ferox cannot be treated as a deep waterindicator as was Th tranquillus in Europe Thus the assem-blage from the shallower zone seems to be rather the equivalentof the Protacrodus biofacies especially when we consider thehigh frequency of protacrodonts1orodonts This being the caseit seems that the names and definitions of biofacies establishedby Ginter (2000) should be revised

Correlation of the deeper zone chondrichthyan assemblagefrom the western USA is much easier Thanks to high frequency


FIGURE 9 Comparison of late Famennian chondrichthyan assemblages from selected European and North African comparative sections Busch-teich East Thuringian Slate Mountains Germany Ostrowka Holy Cross Mountains Poland Soureille drsquoIzarne Montagne Noire France TiziNersas Tafilalt Platform Morocco Rare taxa omitted

of Ph limpidus this assemblage clearly corresponds to thePhoebodus-Thrinacodus biofacies as originally defined How-ever this assemblage differs from typical assemblages from theMontagne Noire or the Holy Cross Mountains by the lack ofsuch widespread taxa as Ph gothicus Jalodus and as alreadynoted Th tranquillus The lack of Jalodus can be explained byits inclination to an open marine lifestyle for it was very com-mon in the oceanic realm of Thuringia (Ginter 1999) and theconditions in the epicratonic seas of western USA were cer-tainly different Presence of barriers composed of land and shal-low water areas such as the Transcontinental arch could also beresponsible for some differences between shark paleocommun-ities from Europe and western USA However the almost totalabsence of Ph gothicus (two strongly abraded specimens werefound from the shallower zone) in the late Famennian (and alsobefore) seems rather unusual since that species occurs not onlyon the eastern side of the Transcontinental arch in the MapleMill Shale of Iowa (Gross 1973) but also in New Mexico(Kietzke and Lucas 1992) The absence of Ph gothicus is prob-ably the reason for the abundance of small Ph limpidus oth-erwise dominated by its bigger relative

The equal distribution of cladodonts in the two zones is aninteresting but already well known situation In all previously

investigated European to African regions cladodont frequencieswere confined to the interval of 22ndash42 (Fig 9) This distri-bution conforming with that from the western USA was to beexpected of facies-independent predatory hunters to whichmost cladodonts apparently belonged (Williams 1990)

Redefinition of Chondrichthyan Biofacies

The original definitions of late Famennian chondrichthyan bio-facies (Ginter 2000) were based on the assumption that the speciesof Phoebodus and Thrinacodus behaved similarly and occupiedgenerally similar niches Now there is evidence that two taxa ofThrinacodus viz Th tranquillus and Th ferox are characteristicof different environments moderately deep shelf and shallow car-bonate platform respectively The former species where foundindeed coexisted with phoebodonts but the latter did not or onlyto a limited extent To avoid confusion it is necessary to changethe name and description of the original Phoebodus-Thrinacodusbiofacies The other two biofacies also require some correctionsHere the following new definitions are proposed

1 Jalodus biofacies more than 25 of Jalodus less than25 of Phoebodus and Thrinacodus tranquillus and less than10 of protacrodonts and orodonts This biofacies representing


deep water open marine areas has not been noted from thewestern USA thus far

2 Phoebodus biofacies more than 25 of Phoebodus andThrinacodus tranquillus It was recorded from the deep andmoderately deep subtidal zones of western USA in this regionTh tranquillus is absent

3 Protacrodus biofacies more than 25 of protacrodontsand orodonts less than 25 of Phoebodus and Th tranquillusThis biofacies is characteristic of the shallow subtidal zone ofwestern USA here Th ferox plays an important role

CONCLUSIONS

It is proposed that the late Famennian chondrichthyan bio-facies model constructed for the areas between South-East Eu-ramerica and Gondwana can be generally applied to the epicra-tonic seas of western Euramerica The pelagic preferences ofphoebodonts (similar to those of palmatolepid conodonts) theshallow water preferences of protacrodonts and orodonts andthe environmental indifference of cladodonts are confirmedThe new finding of the presence of Th ferox in the shallowerareas of Utah is not unexpected However the presence of thistaxon made it necessary partly to redefine the biofacies pro-posed by Ginter (2000) There are apparently only small mor-phological differences between Th ferox and Th tranquilluswhich may cause certain problems Because the two differentspecies of Thrinacodus are now seen to be indicators of differ-ent biofacies it has become indispensable to distinguish onefrom another Identification of the genus even from an incom-plete tooth is usually quite easy However identification to spe-cies level especially when the tooth crown is imperfectly pre-served will require competent and keen observation

ACKNOWLEDGMENTS

My greatest thanks are due to Dr Charles A Sandberg (USGeological Survey Denver) who donated his ichthyolith col-lection to me and provided all the necessary stratigraphic in-formation I am also grateful to my colleagues Dr AlexanderIvanov (St Petersburg University) Dr John Maisey (AmericanMuseum of Natural History New York) Dr Oliver Hampe(Humboldt-Universitat Berlin) Dr Susan Turner (QueenslandMuseum Brisbane) and Dr Margaret Duncan (Trinity CollegeDublin) for the useful discussion on taxonomic problems Myfirst scientific trip to USA in 1997 was partly financed by theBatory Foundation (Fundacja Stefana Batorego Warszawa) andmy parents The costs of my second visit in 2000 and the pro-cessing of the material were covered from the funds of thePolish Committee for Scientific Research (KBN) grant 6 P04D053 18

LITERATURE CITED

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Campbell K S W and R E Barwick 1990 Paleozoic dipnoan phy-logeny functional complexes and evolution without parsimony Pa-leobiology 16143ndash167

Cope E D 1893 On Symmorium and the position of the cladodontsharks American Naturalist 27999ndash1001

Dean B 1909 Studies on fossil fishes (sharks chimaeroids and ar-throdires) American Museum of Natural History Memoir 9211ndash287

De Koninck L 1878 Faune du calcaire carbonifere de la Belgiquepremiere partie Annales du Museum royale drsquoHistoire naturelle deBelgique 21ndash152

Derycke C 1992 Microrestes de selaciens et autres Vertebres du De-vonien superieur du Maroc Bulletin du Museum nationaldrsquoHistoire naturelle 1415ndash61

mdashmdashmdash A Blieck and S Turner 1995 Vertebrate microfauna from theDevonianCarboniferous boundary stratotype at La Serre Montag-

ne Noire (Herault France) Bulletin du Museum national drsquoHistoirenaturelle 17461ndash485

Duffin C 1993 New record of the phoebodontid chondrichthyan Thri-nacodus ferox (Turner 1982) from the Carboniferous of Englandpp 1ndash6 in J Herman and H Van Waes (eds) Elasmobranches etStratigraphie Belgian Geological Survey Professional Paper 264

Duncan M 1999 A study of some Irish Lower Carboniferous fishmicrovertebrates PhD dissertation University of Dublin TrinityCollege Dublin 225 pp

Fournier G and P Pruvost 1922 Decouverte drsquoun Poisson nouveaudans le Marbre noir de Denee Bulletin de la Classe des Sciencesde lrsquoAcademie royale de Belgique 5210ndash218

Garman S 1884 An extraordinary shark (Chlamydoselachus angui-neus) Bulletin of the Essex Institute 1647ndash55

Ginter M 1990 Late Famennian shark teeth from the Holy Cross MtsCentral Poland Acta Geologica Polonica 4069ndash81

mdashmdashmdash 1991 Ichthyofauna pp 74ndash76 in J Hladil Z Krejci J Kal-voda M Ginter A Galle and P Berousek (eds) Carbonate RampEnvironment of Kellwasser Time-interval (Lesni Lom MoraviaCzechoslovakia) Bulletin de la Societe belge de Geologie 100

mdashmdashmdash 1995 Ichthyoliths and Late Devonian events in Poland andGermany pp 23ndash30 in S Turner (ed) Ichthyolith Issues SpecialPublication 1

mdashmdashmdash 1999 FamennianndashTournaisian chondrichthyan microremainsfrom the eastern Thuringian Slate Mountains Abhandlungen undBerichte fur Naturkunde 2125ndash47

mdashmdashmdash 2000 Late Famennian pelagic shark assemblages Acta Geo-logica Polonica 50369ndash386

mdashmdashmdash and A Ivanov 1992 Devonian phoebodont shark teeth ActaPalaeontologica Polonica 3755ndash75

mdashmdashmdash and mdashmdashmdash 1995 MiddleLate Devonian phoebodont-basedichthyolith zonation Geobios Memoire Special 19351ndash355

mdashmdashmdash and mdashmdashmdash 1996 Relationships of Phoebodus Modern Ge-ology 20263ndash274

mdashmdashmdash and mdashmdashmdash 2000 Stratigraphic distribution of chondrichthyansin the Devonian on the East European Platform margin pp 325ndash339 in A Blieck and S Turner (eds) Palaeozoic Vertebrate Bioch-ronology and Global MarineNon-marine Correlation Final Reportof IGCP 328 Courier Forschungsinstitut Senckenberg 223

Glikman L S 1964 Podklas Elasmobranchii Akulovye [SubclassElasmobranchii Sharks] pp 196ndash237 in D V Obruchev (ed)Osnovy paleontologii Beschelustnye ryby Nauka Moscow [Rus-sian]

Gross W 1936 Neue Crossopterygier aus dem baltischen OberdevonZentralblatt fur Mineralogie Geologie und Palaeontologie Abtei-lung B 269ndash78

mdashmdashmdash 1938 Das Kopfskelett von Cladodus wildungensis Jaekel 2Teil Der Kieferbogen Anhang Protacrodus vetustus JaekelSenckenbergiana 20123ndash145

mdashmdashmdash 1956 Uber Crossopterygier und Dipnoer aus dem baltischenOberdevon im Zusammenhang einer vergleichenden Untersuchungdes Porenkanalsystems palaozoischer Agnathen und Fische Kun-gliga Svenska Vetensapsakademiens Handlingar 51ndash140

mdashmdashmdash 1973 Kleinschuppen Flossenstacheln und Zahne von Fischenaus europaischen und nordamerikanischen Bonebeds des DevonsPalaeontographica A 14251ndash155

Harlton B H 1933 Micropaleontology of the Pennsylvanian JohnsValley Shale of the Ouachita Mountains Oklahoma and its rela-tionship to the Mississippian Caney Shale Journal of Paleontology73ndash29

Ivanov A 1996 The Early Carboniferous chondrichthyans of the SouthUrals Russia Geological Society Special Publication 107417ndash425

mdashmdashmdash 1999 Late DevonianndashEarly Permian chondrichthyans of theRussian Arctic Acta Geologica Polonica 49267ndash285

mdashmdashmdash and M Ginter 1996 Early Carboniferous xenacanthids (chon-drichthyes) from eastern Europe Bulletin de la Societe geologiquede France 167651ndash656

mdashmdashmdash and E Luksevics 1994 Famennian chondrichthyans from theMain and Central Devonian Fields Daba un muzejs 524ndash29

Jaekel O 1921 Die Stellung der Palaontologie zur einigen Problemender Biologie und Phylogenie Schadelprobleme PalaontologischeZeitschrift 3213ndash239

Jessen H 1966 Die Crossopterygier des Oberen Plattenkalkes (Devon)der Bergisch-Gladbach-Paffrather Mulde (Rheinisches Schieferge-


birge) unter Berucksichtigung von amerikanischem und europais-chem Onychodus-Material Arkiv for Zoologi 181ndash389

Jones R K and S Turner 2000 Late Devonian fauna from the Col-umbine Sandstone (Coffee Hill Member) Gap Creek central NewSouth Wales pp 523ndash541 in A Blieck and S Turner (eds) Pa-laeozoic Vertebrate Biochronology and Global MarineNon-marineCorrelation Final Report of IGCP 328 Courier ForschungsinstitutSenckenberg 223

Kemp A 1998 On the generic status of Palaeophichthys parvulusEastman 1908 and Monongahela stenodonta Lund 1970 (Ostei-chthyes Dipnoi) Annals of Carnegie Museum 67225ndash243

mdashmdashmdash 2000 Chirodipterus potteri a new Devonian lungfish fromNew South Wales Australia and the ontogeny of chirodipteridtooth plates Journal of Vertebrate Paleontology 20665ndash674

Kietzke K K and S G Lucas 1992 Ichthyoliths from the Devonian-Carboniferous boundary in Sacramento Mountains south-centralNew Mexico USA Ichthyolith Issues 817ndash21

Krupina N I 1987 A new dipnoan fish from the Upper Devonian ofthe Tula Region Paleontological Journal 340ndash47

mdashmdashmdash 1995 Comparison of larval dentition developmental patterns inDevonian and recent dipnoans pp 35ndash38 in S Turner (ed) Ichth-yolith Issues Special Publication 1

mdashmdashmdash and R R Reisz 1999 Reconstruction of dentition in hatch-lings of Andreyevichthys epitomus a late Famennian dipnoan fromRussia Modern Geology 2499ndash108

Lebedev O 1995 Middle Famennian (Upper Devonian) chondri-chthyans and sarcopterygians from Oryol Region Central RussiaGeobios Memoire Special 19361ndash368

mdashmdashmdash and L Vrsquoyushkova 1993 Protacrodontidsmdashthe ancestors ofthe Orodontids pp 51ndash52 in S Turner (ed) The Gross Sympo-sium Scientific sessions abstracts

Leidy J 1873 Contributions to the extinct vertebrate fauna of the west-ern territories Government Printing Office Washington 358 pp

Lelievre H and C Derycke 1998 Microremains of vertebrates nearthe DevonianndashCarboniferous boundary of southern China (HunanProvince) and their biostratigraphical significance Revue de Mi-cropaleontologie 41297ndash320

Long J A 1990 Late Devonian chondrichthyans and other microver-tebrate remains from northern Thailand Journal of Vertebrate Pa-leontology 1059ndash71

Lund R 1974 Stethacanthus altonensis (Elasmobranchii) from theBear Gulch Limestone of Montana Annals of the Carnegie Mu-seum 45161ndash178

Maisey J G 1989 Hamiltonichthys mapesi g amp sp nov (Chondrich-thyes Elasmobranchii) from the Upper Pennsylvanian of KansasAmerican Museum Novitates 29311ndash42

Newberry J S 1889 The Paleozoic fishes of North America USGeological Survey Monograph 161ndash340

Newberry J S and A H Worthen 1866 Descriptions of vertebratesGeological Survey of Illinois 29ndash134

Sandberg C A and R Dreesen 1984 Late Devonian icriodontid bio-facies models and alternate shallow-water conodont zonation Geo-logical Society of America Special Paper 196143ndash178

mdashmdashmdash F G Poole and J G Johnson 1988 Upper Devonian of West-ern United States pp 183ndash202 in N J McMillan A F Embryand D J Glass (eds) Devonian of the World Vol I RegionalSyntheses Canadian Society of Petroleum Geologists Calgary

Scotese C R and W S McKerrow 1990 Revised world maps andintroduction pp 1ndash21 in W S McKerrow and C R Scotese (eds)

Palaeozoic Palaeogeography and Biogeography Geological Soci-ety Memoirs 12

Stevens C H D S Klingman C A Sandberg P Stone P BelaskyF G Poole and J K Snow 1996 Mississippian stratigraphicframework of east-central California and southern Nevada with re-vision of Upper Devonian and Mississippian stratigraphic units inInyo County California US Geological Survey Bulletin 1988-J1ndash39

St John O and A H Worthen 1875 Descriptions of fossil fishesGeological Survey of Illinois 6245ndash488

Turner S 1982 Middle Palaeozoic elasmobranch remains from Austra-lia Journal of Vertebrate Paleontology 2117ndash131

mdashmdashmdash 1983 Taxonomic note on Harpago Journal of Vertebrate Pa-leontology 338

mdashmdashmdash 1991 Palaeozoic vertebrate microfossils in Australasia pp429ndash464 in P Vickers-Rich J M Monaghan R F Baird and TH Rich (eds) Vertebrate Palaeontology of Australasia MonashUniversity Publications Committee Melbourne

mdashmdashmdash 1993 Palaeozoic microvertebrate biostratigraphy of EasternGondwana pp 174ndash207 in J Long (ed) Palaeozoic VertebrateBiostratigraphy and Biogeography Belhaven Press London

Tway L E 1982 Geologic applications of late Pennsylvanian ichth-yoliths from the Midcontinent Region Unpublished PhD disser-tation University of Oklahoma 316 pp

Wang S-T 1989 Biostratigraphy of vertebrate microfossilsVertebratemicrofossils pp 36ndash38 103ndash108 in Q Ji (ed) The DapoushangSection Science Press Beijing

mdashmdashmdash and S Turner 1985 Vertebrate microfossils of the DevonianndashCarboniferous boundary Muhua Section Guizhou Province Ver-tebrata Palasiatica 23224ndash234

mdashmdashmdash and mdashmdashmdash 1995 A re-appraisal of Upper DevonianndashLowerCarboniferous vertebrate microfossils in South China ProfessionalPapers of Stratigraphy and Palaeontology 2659ndash69

Williams M E 1985 The lsquolsquocladodont levelrsquorsquo sharks of the Pennsyl-vanian black shales of central North America PalaeontographicaA 19083ndash158

mdashmdashmdash 1990 Feeding behavior in Cleveland Shale fishes pp 273ndash287in A J Boucot (ed) Evolutionary Paleobiology of Behavior andCoevolution Elsevier Amsterdam

Woodward A S 1891 Catalogue of the Fossil Fishes in the BritishMuseum (Natural History) Part II Containing the Elasmobranchii(Acanthodii) Holocephali Ichthyodorulites Ostracodermi Dipnoiand Teleostomi British Museum of Natural History London 576pp

Xia F-S 1997 Marine microfaunas (bryozoans conodonts and mi-crovertebrate remains) from the FrasnianndashFamennian interval inNorthwestern Junggar Basin of Xinjiang in China Beitrage zurPalaontologie 2291ndash207

Zangerl R 1981 Chondrichthyes I Paleozoic Elasmobranchii pp 1ndash115 in H-P Schultze (ed) Handbook of Paleoichthyology Vol 3AGustav Fischer Stuttgart and New York

Zidek J 1992 Late Pennsylvanian Chondrichthyes Acanthodii anddeep-bodied Actinopterygii from the Kiney Quarry ManzanitaMountains New Mexico New Mexico Bureau of Mines and Min-eral Resources Bulletin 138145ndash182

Ziegler W and C A Sandberg 1984 Palmatolepis-based revision ofupper part of standard Late Devonian conodont zonation Geolog-ical Society of America Special Paper 196179ndash194

mdashmdashmdash and mdashmdashmdash 1990 The Late Devonian standard conodont zo-nation Courier Forschungsinstitut Senckenberg 1211ndash81

Received 20 January 2001 accepted 26 July 2001

714

Journal of Vertebrate Paleontology 21(4)714ndash729 December 2001q 2001 by the Society of Vertebrate Paleontology

CHONDRICHTHYAN BIOFACIES IN THE LATE FAMENNIAN OF UTAH AND NEVADA

MICHAŁ GINTERInstitute of Geology Warsaw University Zwirki i Wigury 93 02ndash089 Warszawa Poland

ABSTRACTmdashLate Famennian assemblages of chondrichthyan microremains especially teeth from Nevada and Utahrepresenting two zones of different water depth are analysed and compared to formerly described pelagic chondri-chthyan biofacies from the areas between S Euramerica and NW Gondwana The assemblage from the deeper (deepto moderately deep subtidal) zone is comparable to the Phoebodus-Thrinacodus biofacies but it lacks such typicalforms as Ph gothicus and Th tranquillus The assemblage from the shallower (shallow subtidal) zone might be anequivalent of the Protacrodus biofacies from which it differs in containing Th ferox and some other shallow watertaxa thus far unknown or very rarely found from the Famennian of central Europe and Africa New definitions ofchondrichthyan biofacies are proposed

INTRODUCTION

Four informal categories of the most common late Famen-nian chondrichthyans based on the gross morphology of teethcan be distinguished in the hitherto described collections ofshark microremains These are cladodonts ie sharks such assymmoriids stethacanthids or Cladoselache (Williams 1985)with teeth characterized by the largest relatively slender centralcusp sharks with tooth-crowns composed of thick and lowpartially or completely fused cusps such as Protacrodus(Gross 1973) phoebodontids (Phoebodus and Thrinacodus)with three delicate sigmoidal main cusps almost equal to eachother (Ginter and Ivanov 1992 Ginter 2000 Turner 1982)and Jalodus (5Phoebodus australiensis Long 1990) with thetooth-crown similar to that of the phoebodontids but with non-sigmoidal cusps ornamented on the labial side with coarseanastomosing cristae It seems that sharks belonging to theabove categories differ in their mode of life and feeding habits(see discussion in Ginter 2000) Cladodonts apparently used tohunt close to the water surface and therefore they could entermany different environments including shallow restricted ep-icratonic gulfs of the Main Devonian Field (Latvia and NWRussia Ivanov and Luksevics 1994) or the late FamennianCleveland Shale Basin an environment characterized by an an-oxic bottom water layer (Williams 1990) Protacrodonts prob-ably lived close to the bottom searching for attached or slowlymoving shelly prey and therefore they needed rather shallowwell oxygenated waters By analogy with a modern shark Chla-mydoselachus anguineus Garman 1884 it is possible to assumethat Phoebodus and Thrinacodus preyed on small fish like pa-laeoniscoids and unarmoured cephalopods They did not enterthe shallow waters of the Main Devonian Field and were veryrare (only a single species Ph politus Newberry 1889) in theCleveland Shale Basin This might suggest that Phoebodus andThrinacodus preferred open shelf environments and were insome way affected by the conditions at the bottom and abovewhich suggests in turn that they lived like Chlamydoselachusrather low in the water column It is difficult to determine themode of life of Jalodus As in the case of the phoebodontidsit is known only from teeth but whereas the phoebodont teethcan be compared to those of Chlamydoselachus the teeth ofJalodus are unlike those of any modern shark or a chondri-chthyan known from articulated skeletons Thus it can only besaid that it apparently represents open marine fauna (Ginter1999)

Recent investigation (Ginter 1999 2000) of pelagic chon-

drichthyan microremains from the late Famennian (Early ex-pansa through EarlyMiddle praesulcata conodont Zones) ofthe regions between the SE Euramerica and NW Gondwana(Fig 1A) showed that the relative abundances of the abovelisted chondrichthyan tooth categories differ in relation to depthandor distance from the land As a result of the study on richcollections mainly from Thuringia (Germany) Montagne Noire(France) Holy Cross Mountains (Poland) and East Anti-Atlas(Morocco) three general chondrichthyan biofacies were pro-posed (Ginter 2000)

1 The deep water Jalodus biofacies in which more than 25is composed of Jalodus teeth and the frequency of PhoebodusThrinacodus or Protacrodus is lower than that

2 The intermediate Phoebodus-Thrinacodus biofacies char-acteristic of moderately deep shelves with more than 25 ofthese two genera counted together

3 The shallow water Protacrodus biofacies with high fre-quency (more than 25) of the latter genus and lower frequen-cy of the other chondrichthyans mentioned above

The term lsquolsquochondrichthyan biofaciesrsquorsquo is understood here asa natural assemblage of chondrichthyan remains (usually onlyteeth) characteristic of a certain type of paleoenvironment TheJalodus biofacies was recorded from the Buschteich section inThuringia representing probably a low submarine rise sur-rounded by deep basinal environments situated far from con-tinental margins This biofacies is also known from Thailand(Long 1990) The Phoebodus-Thrinacodus biofacies occurs inmany carbonate shelf localities like Ostrowka (Holy CrossMountains) Soureille drsquoIzarne (Montagne Noire) or the SouthUrals The assemblage corresponding to the Protacrodus bio-facies was found from shallow water facies of the Tafilalt Plat-form Morocco

Biofacies definitions proposed by Ginter (2000) needed ver-ifying by comparison with some other precisely dated materialfrom a different region of the world Such an opportunity camewith the collection of ichthyoliths from the localities in westernUSA kindly loaned to me by Dr C A Sandberg (USGS Den-ver) Conodonts from these localities were used to create theLate Devonian Standard Conodont Zonation (Ziegler and Sand-berg 1984 1990) and the alternate shallow-water conodont zo-nation (Sandberg and Dreesen 1984) The compound studieson the Devonian of western USA the results of which werepresented by Sandberg et al (1988) were also partly based onthe same localities The present paper concerns only the lateFamennian part of that diverse and rich collection from an arealimited to the states of Utah and Nevada and two further lo-










MATERIAL















2F














pl 2 figs 11ndash12








3 5 Th tranquillus





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MATERIAL















2F














pl 2 figs 11ndash12








3 5 Th tranquillus





5]





































































































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CONCLUSIONS


ACKNOWLEDGMENTS


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MATERIAL















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pl 2 figs 11ndash12








3 5 Th tranquillus





5]





































































































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CONCLUSIONS


ACKNOWLEDGMENTS


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3 5 Th tranquillus





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Documents

Chondrichthyan biofacies in the Late Famennian of Utah and Nevada