Remains of a sea turtle from the Austin Formation (Upper Cretaceous, Campanian), Coahuila, Mexico

Abstract

New remains of a sea turtle from the San Carlos quarry (Upper Cretaceous, Campanian), Austin Formation in the north of Coahuila state, Mexico, are reported. San Carlos quarry is composed of limestones and its Campanian age is based on the presence of the ammonites Scaphites hippocrepis and Delawarella delawarensis. In addition to the presence of turtles, this quarry also contained ammonites, bivalves, crabs, sea urchins, bony fish remains, and shark teeth. The study material is housed at Museo Paleontológico de Múzquiz. The preserved fossil elements correspond to postcranial elements, which present morphological characteristics that allowed them to be identified as belonging to a small-sized turtle related to Protostegidae. These new sea turtle remains expand the knowledge and distribution of Protostegidae along the Western Interior Seaway, where large and medium-sized sea turtles were distributed.