Kimmeridgian pliosaurids (Sauropterygia, Plesiosauria) from Tlaxiaco, Oaxaca, southern Mexico

BARRIENTOS LARA,JAIR; FERNÁNDEZ, MARTA S; ALVARADO ORTEGA, JESUS

REVISTA MEXICANA DE CIENCIAS GEOLóGICAS

CENTRO GEOCIENCIAS UNAM

Lugar: México; Año: 2015

1026-8774

Fossil remains of two specimens of the family Pliosauridae aredescribed in the present manuscript. These fossils are from theKimmeridgian shallow marine strata belonging to the informallyknown Sabinal formation deposited in the Tlaxiaco Basin, which areexposed in Yosobé, near Tlaxiaco town, Oaxaca State, southern Mexico.The first of these specimens consists of a fragment of premaxilla withteeth, which show diagnostic characters that allow its taxonomicalidentification as member of the genus Liopleurodon. The second specimenis preserved by a significantly higher number of bone elements;however, this is only identified as a member of the family Pliosauridae.Despite the shortage of the pliosaurs fossil record so far recovered inYosobé, the specimens described here significantly contribute to theknowledge of this extinct group. On the one hand, these Kimmeridgianfossils are the southernmost representatives of these reptiles discoveredin North America and the first collected in deposits of the HispanicCorridor. On the other hand, the presence of the genus Liopleurodonin this fossil locality confirms its biogeographical distribution into thewestern domain of the Tethys Sea, beyond Europe