Katepensaurus goicocheai gen. et sp. nov., a Late Cretaceous rebbachisaurid (Sauropoda, Diplodocoidea) from central Patagonia, Argentina

LUCIO M. IBIRICU; GABRIEL A. CASAL; RUBÉN D. MARTÍNEZ; MATTHEW C. LAMANNA; MARCELO LUNA; LEONARDO SALGADO

JOURNAL OF VERTEBRATE PALEONTOLOGY

SOC VERTEBRATE PALEONTOLOGY

Lugar: Lawrence; Año: 2013 vol. 33 p. 1351 - 1366

0272-4634

We describe Katepensaurus goicocheai gen. et sp. nov., a diplodocoid sauropod dinosaur from the Bajo Barreal Formation (Upper Cretaceous: Cenomanian?Turonian) of south-central Chubut Province, central Patagonia, Argentina. The holotypic specimen is a closely associated partial axial skeleton that includes cervical, dorsal, and caudal vertebrae. The dorsal vertebrae of Katepensaurus exhibit the following distinctive characters that we interpret as autapomorphies: (1) internal lamina divides lateral pneumatic fossa of centrum; (2) vertical ridges or crests present on lateral surface of vertebra, overlying neurocentral junction; (3) pair of laminae in parapophyseal centrodiapophyseal fossa; (4) transverse processes perforated by elliptical fenestrae; and (5) well-defined, rounded fossae on lateral aspect of postzygapophyses. Based on the results of previous phylogenetic analyses, we regard the new taxon as a member of Rebbachisauridae; more specifically, it probably pertains to Limaysaurinae, a rebbachisaurid subclade that, to date, is definitively known only from southern South America. As currently understood, the rebbachisaurid fossil record suggests that the clade achieved its greatest taxonomic diversity within a few million years of its extinction during the early Late Cretaceous.