Cranial variation in Bairdemys turtles (podocnemididae: Miocene of the Caribbean region) and description of new material from Urumaco, Venezuela

摘要: Synopsis Four new skulls referable to Bairdemys, from the Late Miocene Urumaco Formation in Venezuela, are described and compared with other specimens allocated this genus. Several characters previously used distinguish B. hartsteini (Cibao Formation, middle of Bayamon, Puerto Rico) venezuelensis (Urumaco Formation) present specimens, which show a mosaic features both species as originally diagnosed. Features another Bairdemys skull Castillo early Lara State, Venezuela unique, suggesting is species, but poor preservation known prevents formal diagnosis. In ventral surface secondary palate proportionally larger size, correlated smaller width internal nares distance between foramina palatinae relatively shorter. The position quadrate relation basisphenoid far more posterior ...