THE ORNITHOPOD DINOSAURS FROM THE UPPER CRETACEOUS (BAJO DE LA CARPA FORMATION, SANTONIAN) OF RINCÓN DE LOS SAUCES (NEUQUÉN PROVINCE, ARGENTINA)

PENÉLOPE CRUZADO-CABALLERO; LEONARDO FILIPI; FRANCISCO BARRIOS; ARIEL MÉNDEZ; ARIANA PAULINA-CARABAJAL; ELENA PREVITERA; ALBERTO GARRIDO; LAURA PIPO

Valencia

Congreso; 2nd Palaeontological Virtual Congress 2020; 2020

Universidad de Valencia

The Ornithopoda clade has been traditionally poorly known in the fossil record of the Upper Cretaceous in Argentina. In recent years, the continental sediments outcropping near the Rincón de los Sauces (Neuquén Province, Argentina) have showed a rich record with numerous remains of indeterminate ornithopod, as well as the description of a new specie, Mahuidacursor lipanglef. A recent field work carried out in the outcrops of Bajo de la Carpa Formation (Santonian, Upper Cretaceous), in the area of La Invernada-Cerro Overo, has been fruitful in the discovery of postcranial ornithopod remains from two new sites. The remains present at least two ontogenetic stages, corresponding to an adult and a subadult specimens. Adult individuals would have a medium-size (6 m), similar to other ornithopod remains found in the same area. Almost all postcranial bones collected are poorly diagnosed, except for the ilium MAU-Pv-CO-663. It is a right almost complete ilium (the preacetabular is broken), with a length similar to that of Macrogryphosaurus. Also, MAU-Pv-CO-663 shows a profile more similar to Macrogryphosaurus than Talenkauen, with a rectangular and robust blade and a slender pubic peduncle. Unfortunately, the pelvic girdle of Mahuidacursor is not preserved, preventing further comparison.However, the assignation to this species cannot be discarded. These new fossils increase the knowledge of the Santonian ornithopod fauna from Rincón de los Sauces.