NEW RECORDS OF MARINE TURTLES (TESTUDINES:CHELONIOIDEA} FROM THE MIOCENE OF CHUBUT,ARGENTINA

JULIANA STERLI; EVANGELOS VLACHOS; CUITIÑO, JOSÉ; VIGLINO, MARIANA; BESSONE, SANTIAGO; PUERTA,PABLO FERNANDO

Puerto Madryn

Jornada; Reunion de comunicaciones de la asociación paleotnologica argentina RCAPA 2018; 2018

CCT CONICET-CENPAT IPGP

Miocene. These turtles adapted to marine environments belong to different clades: the extinct Platychelyidae (Pan-Pleurodira) and Thalassochelyidia (Pan-Cryptodira), and the extant Chelonioidea (formed by two clades: Dermochelyidae andCheloniidae). The study of fossil marine turtles has its own challenges, as the cosmopolitan distribution of the extant taxa,and probably the extinct as well, makes any fossil of marine turtles relevant beyond its regional context. Up to now, onlyfragmentary and undetermined specimens of dermochelyids were known for the Miocene marine deposits of Chubut. Re-cent fieldworks leaded by researchers from CENPAT have brought to light an almost complete shell with some postcranialelements of a dermochelyid turtle from Estancia La Redonda Chica (near Trelew). Also, some fragmentary remains werecollected in Bryn Gwyn Geopark (near Gaiman). A partial shell and postcranial remains from Punta Buenos Aires and a par-tial skull (Península Valdés), and a beak (Bryn Gwyn Geopark) are the first records of pan-cheloniids in Chubut.) and PuertoMadryn Formation (Late Miocene). These findings are promising, as they will provide valuable information on the anataxonomy and diversity of the marine turtles that once populated the seas and coasts of Chubut.