Evolution Of The Side-Necked Turtles: The Family Podocnemididae Author Gaffney, Eugene S. Author Meylan, Peter A. Author Wood, Roger C. Author Simons, Elwyn Author De Almeida Campos, Diogenes text Bulletin of the American Museum of Natural History 2011 2011-04-29 2011 350 1 237 http://www.bioone.org/doi/abs/10.1206/350.1 journal article 10.1206/350.1 0003-0090 Peltocephalus Dumeril and Bibron, 1835 TYPE SPECIES : Emys tracaxa Spix (1824) 5 Emys dumeriliana Schweigger (1812) , by monotypy fide Iverson (1992) . INCLUDED SPECIES : Peltocephalus dumerilianus . DISTRIBUTION : Northern South America. DIAGNOSIS : A podocnemidid known from the skull and postcrania; skull relatively high and narrow in contrast to Bauruemys ; elongate, pinched snout in contrast to all podocnemidids except tribe Stereogenyini ; orbits facing laterally in contrast to Podocnemis ; interorbital groove such as found in Podocnemis absent; temporal emargination less than in Podocnemis ; parietal-quadratojugal contact long; cheek emargination absent; postorbital large in contrast to Podocnemis ; medial expansion of triturating surface, median maxillary ridge, present; accessory ridge or ridges present in triturating surface; vomer absent; fossa precolumellaris shallow as in Podocnemis expansa and in contrast to deep as in Erymnochelys ; foramen jugulare posterius closed; jugal-quadrate contact present in contrast to all other podocnemidids except Erymnochelys and UCMP 42008; cavum pterygoidei with large anterior opening and foramen cavernosum in roof; horizontal occipital shelf absent; chorda tympani enclosed in processus retroarticularis. Postcrania with cervical centra saddle shaped; nuchal bone width greater than length; six neurals extending to costal six; first neural four sided; axillary buttress reaches peripheral three in contrast to Erymnochelys ; axillary musk duct in buttress not in bridge; pectoral scales do not contact mesoplastra, but do contact entoplastron and epiplastra. DISCUSSION : Previous literature on this species can be found in Iverson (1992) . See Erymnochelys discussion for original Baur (1890) diagnoses of Recent genera.