Evolution of the Side-Necked Turtles: The Family Podocnemididae

2011·84.8 MB·English

by  Eugene S. Gaffney

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On the cover: Stages in drawing the palate of the ex- 0

tinct side-necked turtle, Stereogenys cromeri Andrews,
1901 (tribe Stereogenyini, family Podocnemididae) from
the Qasr el-Sagha Fm., late Eocene, Fayum Depression, 2
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1 BULLETIN OF THE AMERICAN MUSEUM OF NATURAL HISTORY
Egypt, by Frank Ippolito. 1
EVOLUTION OF THE SIDE-NECKED TURTLES:
THE FAMILY PODOCNEMIDIDAE
EUGENE S. GAFFNEY
Division of Paleontology
American Museum of Natural History
New York, New York
PETER A. MEYLAN
Richard R. Hallin Professor of Natural Sciences
Collegium of Natural Science
Eckerd College, St Petersburg FL 33711
ROGER C. WOOD
Faculty of Sciences and Mathematics
Richard Stockton College of New Jersey
Pomona, NJ 08240
ELWYN SIMONS
James B. Duke Professor of Anthropology
Department of Biological Anthropology and
Anatomy, and Primate Center
Duke University, Durham, NC 27705
DIOGENES DE ALMEIDA CAMPOS
Departmento Nacional da Produc¸ao Mineral
Rio de Janeiro, Brasil
BULLETINOFTHEAMERICANMUSEUMOFNATURALHISTORY
Number350, 237 pp., 98figures, 4tables
IssuedApril29,2011
CopyrightEAmericanMuseumofNaturalHistory2011 ISSN0003-0090
CONTENTS
Abstract . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Institutional Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Anatomical Abbreviations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Summary Classification. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Systematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Hyperfamily Pelomedusoides Cope, 1868 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Epifamily Podocnemidinura Cope, 1868 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Family Podocnemididae Cope, 1868 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Subfamily Bauruemydinae, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Bauruemys Kischlat, 1994. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Bauruemys elegans (Sua´rez, 1969a). . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Subfamily Podocnemidinae Cope, 1868 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Infrafamily Peiropemydodda, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Peiropemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Peiropemys mezzalirai, n. gen. et sp. . . . . . . . . . . . . . . . . . . . . . . . . . 23
Lapparentemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Lapparentemys vilavilensis (Broin, 1971) n. comb. . . . . . . . . . . . . . . . . 25
Pricemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Pricemys caiera, n. gen. et sp. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Infrafamily Podocnemidodda Cope, 1868, new rank . . . . . . . . . . . . . . . . . . . 27
Magnatribe Podocnemidand Cope, 1868, new rank . . . . . . . . . . . . . . . . . . 27
Podocnemis Wagler, 1830. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Podocnemis expansa (Schweigger, 1812) . . . . . . . . . . . . . . . . . . . . . . . 29
Podocnemis vogli Mu¨ller, 1935. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
Podocnemis lewyana Dume´ril, 1852 . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Podocnemis sextuberculata Cornalia, 1849. . . . . . . . . . . . . . . . . . . . . . 30
Podocnemis unifilis Troschel, 1848 . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
Podocnemis erythrocephala (Spix, 1824) . . . . . . . . . . . . . . . . . . . . . . . 30
Podocnemis bassleri Williams, 1956 . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Magnatribe Erymnochelydand Broin, 1988, new rank . . . . . . . . . . . . . . . . 31
Caninemys Meylan, Gaffney, and Campos, 2009 . . . . . . . . . . . . . . . . . . 31
Caninemys tridentata Meylan, Gaffney, and Campos, 2009 . . . . . . . . . 33
Dacquemys Williams, 1954b . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Dacquemys paleomorpha Williams, 1954b . . . . . . . . . . . . . . . . . . . . . . 34
Albertwoodemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Albertwoodemys testudinum, n. gen et sp. . . . . . . . . . . . . . . . . . . . . . . 35
UCMP 42008, unnamed new genus and species . . . . . . . . . . . . . . . . . . . 37
Turkanemys Wood, 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Turkanemys pattersoni Wood, 2003 . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Erymnochelys Baur, 1888 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Erymnochelys madagascariensis (Grandidier, 1867) . . . . . . . . . . . . . . . 40
Peltocephalus Dumeril and Bibron, 1835 . . . . . . . . . . . . . . . . . . . . . . . . 41
Peltocephalus dumerilianus (Schweigger 1812) . . . . . . . . . . . . . . . . . . . 41
Neochelys Bergounioux, 1954 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Neochelys arenarum Broin, 1977 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Neochelys fajumensis (Andrews, 1903) n. comb. . . . . . . . . . . . . . . . . . 43
Papoulemys Tong, 1998 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Papoulemys laurenti Tong, 1998. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Tribe Stereogenyini, new. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Subtribe Mogharemydina, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
2
Mogharemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Mogharemys blanckenhorni Dacque´ (1912), n. comb.. . . . . . . . . . . . . 47
Subtribe Stereogenyina, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Infratribe Bairdemydita, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Cordichelys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Cordichelys antiqua (Andrews, 1903), n. comb. . . . . . . . . . . . . . . . . . 49
Latenemys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Latenemys plowdeni, n. gen. et sp. . . . . . . . . . . . . . . . . . . . . . . . . . 51
Bairdemys Gaffney and Wood, 2002 . . . . . . . . . . . . . . . . . . . . . . . . . . 51
Bairdemys hartsteini Gaffney and Wood, 2002 . . . . . . . . . . . . . . . . . 52
Bairdemys venezuelensis (Wood and D´ıaz de Gamero, 1971). . . . . . . . 52
Bairdemys winklerae Gaffney et al., 2008 . . . . . . . . . . . . . . . . . . . . . 53
Bairdemys sanchezi Gaffney et al., 2008 . . . . . . . . . . . . . . . . . . . . . . 53
Infratribe Stereogenyita, new . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Brontochelys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Brontochelys gaffneyi (Wood, 1970), n. comb. . . . . . . . . . . . . . . . . . 54
Lemurchelys, n. gen. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Lemurchelys diasphax, n. gen. et sp. . . . . . . . . . . . . . . . . . . . . . . . . 55
Shweboemys Swinton, 1939. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Shweboemys pilgrimi Swinton, 1939 . . . . . . . . . . . . . . . . . . . . . . . . . 56
Stereogenys Andrews, 1901. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Stereogenys cromeri Andrews, 1901 . . . . . . . . . . . . . . . . . . . . . . . . . 57
Dubious Taxa . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Podocnemididae Incertae Sedis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Cambaremys langertoni Franc¸a and Langer, 2005. . . . . . . . . . . . . . . . . . . . . . . . 58
Cerrejonemys wayuunaiki Cadena, Bloch, and Jaramillo, 2010. . . . . . . . . . . . . . . 59
Kenyemys williamsi Wood, 1983 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Peiro´polis A, unnamed shell taxon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Peiro´polis B, unnamed shell taxon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62
‘‘Podocnemis’’ argentinensis Cattoi and Freiburg, 1958 . . . . . . . . . . . . . . . . . . . . 63
‘‘Podocnemis’’ geologorum Simpson, 1943 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
‘‘Podocnemis’’ medemi Wood, 1997. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
‘‘Podocnemis’’ negrii Carvalho, Bocquentin, and Lapparent de Broin, 2002. . . . . . 64
‘‘Podocnemis’’ pritchardi Wood, 1997 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Roxochelys wanderleyi Price, 1953. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
‘‘Stereogenys’’ libyca Andrews, 1903 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Stupendemys geographicus Wood, 1976 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
Taxa Nomina Dubia. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Duerochelys arribasi Jime´nez, 1975 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Latisternon microsulcae Auffenberg, 1981 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
‘‘Podocnemis’’ aegyptiaca Andrews, 1900. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
‘‘Podocnemis’’ bramlyi Fourteau, 1920. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
‘‘Podocnemis’’ brasiliensis Staesche, 1937 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
‘‘Podocnemis’’ freibergi Agnolin, 2004 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
‘‘Podocnemis’’ harrisi Pacheco, 1913 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
‘‘Stereogenys’’ podocnemoides Reinach, 1903b . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Cranial Morphology of Lapparentemys, Pricemys, Peiropemys, and Bauruemys . . . . . . 71
Cranial Morphology of the Tribe Stereogenyini . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Mogharemys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
Cordichelys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Latentemys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Brontochelys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Lemurchelys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
3
Shweboemys. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
Stereogenys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 171
Shell morphology of South American Late Cretaceous and Early Tertiary
Podocnemidids . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
Phylogenetic Analysis. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Previous Work. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Character Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 208
Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 224
References. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225
Appendix 1. Character Matrix. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Appendix 2. Character List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 235
Appendix 3. Measurements of Podocnemidid Skulls . . . . . . . . . . . . . . . . . . . . . . . . . 237
4
ABSTRACT
ThefamilyPodocnemididaeconsistsof20generaand30speciesconsideredhereasvalidand
diagnosablebycranialcharacters.ThreeofthesegeneraandeightspeciespersistintotheRecent
fauna, barely reflecting the evolutionary diversity and distribution of the group. The family
extends from the Late Cretaceous to the Recent and occurs in North and South America,
Europe,Asia,andAfrica.Aphylogeneticanalysisutilizes31podocnemididtaxa(30namedand
oneunnamed;a totalof37taxa analyzedincludesoutgroups)inthe Podocnemididaethatare
analyzedusingPAUP.Theresultingconsensusofnineequallyparsimoniouscladogramsisthe
basis for a new classification of the family. The family Podocnemididae is reconfirmed as
monophyletic,usingtheuniquepossessionofacavumpterygoideiformedbythebasisphenoid,
pterygoid, prootic, and quadrate, underlain by the pterygoid and basisphenoid, among other
characters.MuchofourresolutionagreeswiththatofFranc¸aandLanger(2006),whichcanbe
modified and restated as follows: (Bauruemys (vilavilensis (Podocnemis (Peltocephalus,
Erymnochelys)))). The two clades proposed by Broin (1991) and Lapparent de Broin (2000b,
2001,2003a,2003b),designatedbyherasthe‘‘subfamilyPodocnemidinae’’andthe‘‘subfamily
Erymnochelinae,’’ are inconsistent with our analysis. In our analysis the ‘‘Podocnemidinae’’
(sensu Broin, 1991) is paraphyletic, and the ‘‘Erymnochelinae’’ (sensu Broin, 1991) could be
made monophyletic, with the important addition of Peltocephalus (placed in the ‘‘Podocnemi-
dinae’’ byBroin).
WeaddanumberofnewtaxatothebasalPodocnemididaeandtothebroad-jawedsubtribe
Stereogenyina. Within the family Podocnemididae Cope, 1868, the sister taxon to all other
podocnemidids and recognized as the subfamily Bauruemydinae, new, is Bauruemys elegans
(Sua´rez, 1969a), known from associated skulls and shells. All other podocnemidids, the
redefined subfamily Podocnemidinae Cope, 1868, are united by a slight to absent temporal
emargination,acompletelyclosedforamenjugulareposterius,andsaddle-shapedcervicalcentra
(modified as a separate state in Erymnochelys). A basal group of Cretaceous-Paleocene
podocnemidids that are the sister group to all remaining podocnemidids, here termed the
infrafamily Peiropemydodda, consisting of two taxa from the late Cretaceous of Brazil,
Peiropemys mezzalirai, n. gen. et sp., and Pricemys caiera, n. gen. et sp., and Lapparentemys
vilavilensis (Broin, 1971), n. gen., from the Paleocene of Bolivia. The resolution of the basal
members of the family is: (Bauruemys (Pricemys (Lapparentemys, Peiropemys)) (Infrafamily
Podocnemidodda)).
TheremainingpodocnemididsformtheinfrafamilyPodocnemidoddaCope,1868,newrank,
and is characterized by the possession of a cheek emargination that does not reach above the
leveloftheorbit,themedialexpansionofthetrituratingsurfaceswithamedianmaxillaryridge
present,andthepresenceofaccessoryridgesonthetrituratingsurfaces.Thisgroupcontainsthe
living podocnemidids and a series of extinctforms, includingthe marine broad-jawedtaxa.
Within the Podocnemidodda, the genus Podocnemis is the sister group to all the remaining
taxa,whichisthemagnatribeErymnochelydand.Whenonlythelivingfaunaisconsideredour
resultsshowPodocnemisasthesistertaxontoErymnochelysplusPeltocephalus,incommonwith
Williams (1954c), Franc¸a and Langer (2006), Meylan et al. (2009), and Cadena et al. (2010).
Withthefossil taxapresent,theErymnochelydand isunitedonlybythesmalltoabsentcheek
emargination.However,someofthefossiltaxa(i.e.,Caninemys,Dacquemys),arenotknownfor
a number of characters, and, if the analysis is reduced to include only the living species,
Erymnochelys and Peltocephalus are united by a greater number of characters: cavum
pterygoidei with enlarged anterior opening, so that the foramen cavernosum enters the roof
of the cavum pterygoidei, orbits facing anterolaterally, jugal-quadrate contact present, cheek
emargination slight to absent, horizontal occipital shelf absent, premaxillae reach apertura
nariuminterna(alsoinsomePodocnemis),supraoccipitalroofexposureslightorabsent,chorda
tympani enclosed in processus retroarticularis, neural series extends to costal six, and axillary
musk ductnotinbridge.
WhenoneconsidersjusttheRecentgenera,noneofthepublishedmolecularresultsreproduce
the Gaffney and Meylan (1988) and Lapparent de Broin (2000b) resolution of (Erymnochelys
(Podocnemis,Peltocephalus));ratherthesepublicationsshowapreferenceforthe(Peltocephalus
(Podocnemis, Erymnochelys)) arrangement, while we, in agreement with Franc¸a and Langer
(2006)andtheearlierversionofthepresentdataset,Meylanetal.(2009),placeourmarbleswith
the third alternative, (Podocnemis (Peltocephalus, Erymnochelys)). This latter hypothesis has a
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6 BULLETIN AMERICAN MUSEUM OFNATURALHISTORY NO.350
number of characters favoring its resolution, even when fossils are excluded. One of the more
compelling ones is the large cavum pterygoidei with an enlarged anterior opening and the
foramen cavernosum containing the lateral head vein, entering the roof of the cavum
pterygoidei.
Within the magnatribe Erymnochelydand are the following taxa: Caninemys, Dacquemys,
unnamed genus UCMP 42008, Albertwoodemys, Turkanemys, Peltocephalus, Erymnochelys,
Neochelys,Papoulemys,andthemembersofthetribeStereogenyini(seebelow).Theresolution
of Caninemys within the Erymnochelydand is not strongly supported; in only one step it
becomes a multichotomy with Podocnemis and the infrafamily Peiropemydodda. Neochelys,
Papoulemys (possibly a synonym of Neochelys), and Dacquemys, however, are strongly
supported as part of the magnatribe Erymnochelydand, as proposed earlier (Broin, 1991;
Lapparentde Broin, 2000b,2001, 2003a,2003b).
A new shell-based taxon, Albertwoodemys testudinum, n. gen. et sp., and an unnamed skull
and shell, UCMP 42008, are united by a high-domed shell with thick lateral ridges along the
plastron and the absence/fusion of the pectoral scales. The skull of UCMP 42008 agrees with
thatinDacquemysinhavinglargeparietalsandasupraoccipitalcoveringtheposteriormargin.
Lackingaskull,Albertwoodemysisnotenteredintothedataset,buttheskull-shellspecimenof
theclosely related UCMP42008 isintheanalysis.
New skull material identifiable as Neochelys has been discovered associated with shells of
‘‘Podocnemis’’fajumensisAndrews,1903,resultinginthenewcombinationNeochelysfajumensis
(Andrews, 1903). Neochelys has the Erymnochelydand synapomorphy of a large cavum
pterygoideiwithanenlargedanterioropeningandtheforamencavernosumenteringtheroofof
thecavumpterygoidei,asinPeltocephalusandErymnochelys.TheEuropeanNeochelysspecies
are Eocene and the African Fayum species is Early Oligocene, extending both spatial and
temporal rangesof the genus.
The tribe Stereogenyini has a dorsal process of the palatine that reaches the frontal in the
septumorbitotemporale,thefossaprecolumellarisisabsent,andbothforaminanervihypoglossi
arecombinedandrecessedinashortcanalthatopensontheoccipitalsurface.Withinthetribe
Stereogenyini,MogharemysblanckenhorniDacque´(1912),n.gen.,isthesistertaxontothewell-
defined subtribeStereogenyina.
Two groups are recognized within the subtribe Stereogenyina. The infratribe Bairdemydita
containsBairdemysGaffneyandWood,Latentemysplowdeni,n.gen.etsp.,Cordichelysantiqua
(Andrews, 1903), n. gen. The infratribe Stereogenyita contains Brontochelys gaffneyi (Wood,
1970),n.gen.,Lemurchelysdiasphax,n.gen.etsp.,ShweboemysSwinton,1939,andStereogenys
Andrews,1901.ThesubtribeStereogenyinaisstronglysupportedbyasecondarypalatewitha
mediancleft,uniqueamongturtles,aswellasothercharacters.WhiletheotherPodocnemididae
were apparently freshwater species, there is evidence that many or all of the subtribe
Stereogenyinaweremarineornear-shore marine.
Compared with a group such as the Bothremydidae, we see in the evolution of the
Podocnemididae, a relatively conservative series of South American paraphyletic taxa with an
unusuallypersistentcranialaswellasshellmorphology,beginningintheLateCretaceouswith
Bauruemys, Peiropemys, and Pricemys, and continuing with the Paleocene Lapparentemys,
culminating in the Recent Podocnemis. A monophyletic Tertiary group with more geographic,
taxonomic, and morphologic diversity, the magnatribe Erymnochelydand, contains African,
European, Asian, and South American taxa, as well as a radiation of marine, broad-jawed
species in the mid-Tertiary. The living remnants of the Erymnochelydand are the South
American Peltocephalus and the African Erymnochelys, close relatives despite their current
geographicseparation.
INTRODUCTION record shows that the wider group, the
epifamily Podocnemidinura, containing po-
The Cretaceous to Recent pleurodire fam- docnemididsplustheirnearrelatives,extends
ily Podocnemididae occurs in North and back to the early Cretaceous in South
South America, Europe, Asia, and Africa, America. The living species are freshwater,
althoughthesurvivingspeciesarerestrictedto but the fossil record shows that a predomi-
South America and Madagascar. The fossil nantly marine/near-shore marine clade, the
2011 GAFFNEYETAL.: THE FAMILY PODOCNEMIDIDAE 7
subtribe Stereogenyina, was present in the cent species of Podocnemididae; rather, we
Tertiary of northern South America, the emphasize documentation of the previously
NorthAmericancoastalplain,theCaribbean, undescribedorpoorlyknownfossil taxa that
northernAfrica, andwesternAsia (Burma). arerepresentedbynewlydiscoveredskullsor
The present paper is a documentation and skull-shell associations.
phylogenetic analysis of the family Podocne- One of the serious problems in analyzing
mididae, and is a direct continuation of these podocnemidid taxa (and others among
Gaffney et al. (2006). It is very similar in thePleurodira)isthepersistentreferralinthe
purpose, scope, and treatment. We rely on literature to taxa that are diagnosable as
the Introduction, Previous Work, Organiza- species or some level of alpha taxon, but
tion, and Systematics sections of Gaffney et possess too few characters to reasonably
al. (2006), which all contain explanatory resolve in a phylogenetic analysis that would
information pertaining to the present paper allow them to be confidently placed within a
that is not repeated here. Treatment of the genus or some other higher level taxon. This
higher categories above the family Podocne- problem is particularly apparent for a num-
mididae are also in Gaffney et al. (2006); berofshelltaxathatcanbediagnosedatthe
diagnoses, phylogenetic analyses, and litera- specieslevel,and insome casesarenamed as
tureforthesetaxaarenotrepeatedhere.This monospecific genera, but that cannot be
paperfocusesonthefamilyPodocnemididae. objectively related to groups within the
Wenameninenewgeneraanddescribethe family, except by arbitarily choosing one or
skulls of 11 genera. Additionally, the shell two characters. A significant factor in this
morphology of some South American Creta- problem, repeatedly emphasized in the study
ceous and Paleocene taxa is described, of Pelomedusoides (Gaffney et al., 2006), is
including some with skull-shell associations. theconservativenature of theshell morphol-
All of the named podocnemidids that are ogyofPelomedusoidesturtles.Itisthebroad
represented by diagnosable material are phylogenetic distribution of this highly con-
treated and diagnosed. We discuss a series served shell morphotype that has led to the
of diagnosable taxa that are not phylogenet- liberal use of the generic epithet ‘‘Podocne-
ically resolvable in our analysis and are mis’’ for fossil shells, which may belong to
referredtoasPodocnemididae,incertaesedis. either the Podocnemididae or the Bothremy-
A further eight taxa, often referred to the didae. A modification of this tendency is to
Podocnemididae, are undiagnosable and usesomeautapomorphiestoraiseaspeciesto
considered nomina dubia. The analysis relies genericlevel.However,ifthetaxonstilllacks
mostlyoncranialcharactersandtaxaknown enough comparative characters to use in a
onlyfromtheshellarepoorlyresolvedinour phylogeny, it seriously hampers analysis of
analysis. the diversity that is known. Gaffney et al.
Although we present our conclusions as a (2006) dealt with this problem by placing
phylogenetic analysis, the description and these taxa at various levels of incertae sedis,
documentation of the morphology of these and that is what we do here.
taxa is our primary purpose, as it was in As part of our Podocnemididae project,
Gaffney et al. (2006). The newly described the reader is directed to earlier papers on
material is mostly from two groups, the so- podocnemidids in this series: Gaffney et al.
called ‘‘basal’’ South American Cretaceous- (1998), Gaffney et al. (2002), Gaffney and
Paleocene Podocnemididae, here termed the Wood (2002), Gaffney and Forster (2003),
infrafamily Peiropemydodda, lying outside Gaffney et al. (2006), Gaffney et al. (2008),
the common ancestor of the living species, and Meylan et al. (2009). The cranial
and the mid-Tertiary, broad-jawed, presum- morphology of turtles and an illustrated
ably brackish to marine, tribe Stereogenyini. compilation of morphologic terminology
Wealsoincludenewfiguresandcomparative can be found in Gaffney (1972, 1979). An
information about other Podocnemidinura introduction to the cranial morphology of
(i.e., Neochelys, Hamadachelys, and some of pleurodires can be found in Gaffney et al.
therecentspeciesofPodocnemis).Wedonot (2006). Previous work on the Podocnemidi-
review alpha-level problems within the Re- dae is treated below under the relevant taxa
8 BULLETIN AMERICAN MUSEUM OFNATURALHISTORY NO.350
and previous systematic work is in Phyloge- de Produc¸a˜o Mineral, Rio de
netic Analysis. We restrict ourselves to Janeiro, Brazil
studies pertaining to systematics and mor- MCZ Museumof ComparativeZoolo-
phology and do not include conservation, gy, Harvard University, Cam-
ecology, or other biologic features of the bridge, Massachusetts
family except where they relate to systematic MCNC Museo de Ciencias Naturales,
problems. Caracas, Venezuela
MDE Muse´e de Dinosaures, Espe´raza,
INSTITUTIONAL ABBREVIATIONS France
MHNC Museo de Historia Natural de
Cochabamba,Cochabamba,Bo-
AMNH American Museum of Natural
livia
History, New York, New York
MNHN Muse´umnationald’Histoirenat-
AMU- Alcald´ıa del Municipio Uru-
urelle, Paris, France
CURS maco, Coleccio´n Rodolfo Sa´n-
MNHNP Paleontology, Muse´um national
chez, Venezuela
d’Histoire naturelle, Paris,
BMNH Natural History Museum, Lon-
France
don, Great Britain
MN-V Setor de Paleovertebrados, De-
CGM Cairo Geological Museum,
partmentodeGeologiaePaleon-
Egypt
tologia, Museu Nacional, Uni-
CPP Centro de Pesquisas Paleontolo´-
versidade Federal do Rio de
gicas ‘‘Llewellyn Ivor Price,’’
Janeiro, Brazil
Uberaba, Brazil
MNRJ Museu Nacional, Universidade
MAC Musee Royale d’Afrique Cen-
FederaldoRiodeJaneiro,Brazil
trale, Tervuren, Belgium
NFWFL National Fish and Wildlife Fo-
DGM Divisa˜o de Geologia e Minera-
rensics Laboratory, Oregon
logia, Departamento Nacional
NMV Naturhistorisches Museum,
de Produc¸a˜o Mineral, Rio de
Vienna, Austria
Janeiro, Brazil
UCMP University of California, Muse-
DNPM Departamento Nacional de Pro-
um of Paleontology, Berkeley,
duc¸a˜o Mineral, Rio de Janeiro,
California
Brazil
UFAC-PV Laboratorio de Paleontologia,
DPC Duke Primate Center, Duke
Universidade Federal do Acre,
University, Durham, North
Rio Branco, Brazil
Carolina
UFRGS Universidade Federal do Rio
FCUS Faculty of Sciences of the Uni-
Grande do Sul, Porto Alegre,
versity of Salamanca, Spain
Brazil
FMNH Field Museum of Natural
USNM UnitedStatesNationalMuseum,
History, Chicago, Illinois
Washington, DC
IGM Instituto de Investigaciones en
UF Florida Museum of Natural
Geosciencias, Miner´ıa y Qu´ı-
History, University of Florida,
mica, Museo Geolo´gico Bogota´,
Gainesville, Florida
Bogota´, Colombia
WUS School of International Liberal
LACM NaturalHistory MuseumofLos
Studies, Waseda University,
Angeles County, California
Tokyo, Japan
MACN Museo Argentino de Ciencias
Naturales, Buenos Aires, Argen-
tina ANATOMICAL ABBREVIATIONS
MB Museum fur Naturkunde, Ber-
lin, Germany ab abdominal scale
MCT Divisa˜o de Geologia e Minera- acst aditus canalis stapedio-tempo-
logia, Departamento Nacional ralis
2011 GAFFNEYETAL.: THE FAMILY PODOCNEMIDIDAE 9
ana anal scale hypo hypoplastron
ani apertura narium interna ib inguinal buttress
ap antrum postoticum ica incisura columellae auris
ax axillary buttress ils iliac scar
bo basioccipital in intergular scale
bs basisphenoid ju jugal
ca columella auris ma marginal scale
cc canalis cavernosus me mesoplastron
ccr cavum cranii mx maxilla
cl cavum labyrinthicum ne neural bone
cos costal bone nu nuchal bone
cpt cavum pterygoidei op opisthotic
ct cavum tympani
pa parietal
ds dorsum sellae
pal palatine
ent entoplastron
pec pectoral scale
epi epiplastron
per peripheral bone
ex exoccipital
pf prefrontal
facci foramen anterius canalis carotici
pg pygal bone
interni
pip processus inferior parietalis
faf fossa acustico-facialis
pl processus clinoideus
fc foramen cavernosum
pm premaxilla
fcti foramenchordatympaniinferius
po postorbital
fem femoral scale
pr prootic
fio foramen interorbitale
pt pterygoid
fja foramen jugulare anterius
ptf pterygoid flange
fjp foramen jugulare posterius
ptp processus trochlearis pterygoidei
fn fossa nasalis
qj quadratojugal
fnf foramen nervi facialis
qu quadrate
fnt foramen nervi trigemini
rb rostrum basisphenoidale
fo fenestra ovalis
se sulcus eustachii
fon foramen orbito-nasale
sf sulcus olfactorius
fp foramen praepalatinum
fpc fossa precolumellaris so supraoccipital
fpcci foramen posterius canalis caro- sot septum orbitotemporale
tici interni spg suprapygal
fpo fenestra postotica spt sulcus palatinopterygoideus
fpp foramen palatinum posterius sq squamosal
fr frontal st sella turcica
fst foramen stapedio-temporale VII foramen nervi facialis
gu gular scale VIII foramen nervi acustici
ha hiatus acusticus vo vomer
hu humeral scale XII foramen nervi hypoglossi
hyo hyoplastron xip xiphiplastron