First record of Crocodyliformes Osteoderm from the Upper Cretaceous Bauru Group, State of Goiás, Brazil

Abstract

The Crocodyliformes from the Late Cretaceous of South America were one of the main components of the tetrapod faunas found in rocks of the Bauru Group at Goiás, Minas Gerais and São Paulo states, Brazil. The presence of osteoderms has been reported in articulated specimens or found isolated in the palaeontological record. In the present work, we describe the first osteoderm of Mesoeucrocodylia from the Campanian-Maastrichtian of the Marília Formation (Bauru Group) of the state of Goiás. Paleo-UFG-114 has a quadrilateral shape, a rough external texture with radially oriented corrosion, an internal facet with the presence of intersecting grooves, foramina in the internal and external region and the presence of a poorly developed keel. These features differentiate them from the osteoderms of titanosaur dinosaurs found in the rocks of this geological unit. The presence of Paleo-UFG-114 in the state of Goiás reaffirms that mesoeucrocodylians were important components of the reptile fauna, and contributes to increasing knowledge about the group’s geographic distribution in this poorly-explored region of Central Brazil.