Bairdemys venezuelensis

Gaffney, Eugene S., Meylan, Peter A., Wood, Roger C., Simons, Elwyn & De Almeida Campos, Diogenes, 2011, Evolution Of The Side-Necked Turtles: The Family Podocnemididae, Bulletin of the American Museum of Natural History 2011 (350), pp. 1-237 : 52-53

Bairdemys venezuelensis

( Wood and Díaz de Gamero, 1971)

TYPE SPECIMEN: Laboratorio de Paleontología, Universidad Central de Venezuela (Caracas), VF 1176, a complete carapace figured by Wood and Díaz de Gamero (1971: pls. 1, 2, 4).

TYPE LOCALITY: ‘‘North of Campo El Mamón, state of Falcón, Venezuela’’ ( Wood and Díaz de Gamero, 1971).

HORIZON: Late Miocene, Urumaco Formation.

DIAGNOSIS: A species of Bairdemys differing from all other species in having a higher anterior triturating surface convexity, a deeper posterior triturating surface concavity, and a short midline contact of the pterygoids; also differs from B. hartsteini in having a larger skull, a convex labial ridge in ventral view, no premaxillary notch, and a wider posterior triturating surface; also differs from B. sanchezi in having a wider skull, a wider posterior triturating surface, a larger basisphenoid, no premaxillary notch, and a less extensive cheek and temporal emargination; also differs from B. winklerae in having a broad, convex, and short snout, a slightly wider skull, a wider posterior triturating surface, and a narrower basisphenoid-quadrate contact.

ETYMOLOGY: For the country of Venezuela.

REFERRED MATERIAL: See list in Gaffney and Wood (2002).

PREVIOUS WORK: Wood and Díaz de Gamero (1971), Gaffney and Wood (2002), Sánchez-Villagra and Winkler (2006), Gaffney et al. (2008), Sánchez-Villagra and Scheyer (2010). Winkler and Sánchez-Villagra (2006) describe eggs from a likely Bairdemys venezuelensis nesting site, indicating that it was a colonial nester laying its eggs in beaches and living in a marine or near shore marine environment. Sánchez-Villagra and Scheyer (2010) provide a useful overview of the Venezuelan fossil turtles.

DISCUSSION: Although this is the oldest named species in the currently construed genus Bairdemys , the type species is hartsteini , named by Gaffney and Wood (2002) so that the genus had a skull as its type species, in case some or all of the shell features of B. venezuelensis prove to be taxonomically widespread, as is in fact the case according to Gaffney et al. (2006). Fortunately, the MCZcollected specimens consist of skulls and shells from the same quarry ( Gaffney and Wood, 2002). The large size, broad snout, and straight labial ridge (in anterior view) are characteristic of this species.