HALLAZGO DE VERTEBRADOS FÓSILES EN LA FORMACIÓN LONCOCHE, CRETÁCICO SUPERIOR DE LA PROVINCIA DE MENDOZA, ARGENTINA

GONZÁLEZ RIGA, BERNARDO J.

AMEGHINIANA

Asociación Paleontológica Argentina

Lugar: Buenos Aires; Año: 1999 p. 401 - 410

0002-7014

DISCOVERY of fossil vertebrates in the LoncocHe Formation, Upper Cretaceous OF Mendoza province, Argentina.  The discovery of a rich assemblage of fossil vertebrates from the lower section of the Loncoche Formation in Ranquil-Có, southern Mendoza province, Argentina, is repported here. This assemblage is composed of fishes, amphibians and reptiles. The fishes include Rajiformes indet., cf. Atractosteus sp (Lepisosteidae, Semionotiformes), Percodei indet. (Perciformes) and Ceratodus sp (Ceratodontidae, Dipnoi). The amphibians include ?Leptodactylidae indet. (Anura). The reptiles include Chelidae indet. (Chelonii), Boidae indet. (Serpentes), Theropoda indet. and Titanosauria indet. (Saurischia), and Plesiosauria indet. The remains were found in a tidal paleoenvironment; this account for transportation, mixing and deposition of continental animal remains mixed with those from near coastal environments. This agrees with our sedimentological interpretation of the Loncoche Formation. Similar stratigraphic units from northern Patagonia (e.g. Allen and Los Alamitos Formations) record a progressive marine transgression up to the end of the Cretaceous Period and show similar paleovertebrate assemblages. In particular, the Loncoche fauna is related to that recorded in the Los Alamitos Formation (Río Negro Province), allowing us to assign to it a tentative age of late Campanian to early Maastrichtian. This age is agrees with micropaleontological data recorded in both units. Key words: Argentina. Mendoza. Loncoche Formation. Upper Cretaceous. Vertebrates. Stratigraphy. Palabras clave: Argentina. Mendoza. Formación Loncoche. Cretácico Superior. Vertebrados. Estratigrafía.