Assignable material to Epachthosaurus Powell, 1990 (Sauropoda: Titanosauria), from the Bajo Barreal Formation, Upper Cretaceous, Chubut, Argentina

This paper describes materials recovered from levels of the Bajo Barreal Formation (Upper Cretaceous) of Ranch Ocho Hermanos outcrops, Patagonia, Argentina.The materials include an anterior dorsal vertebra and pelvic elements.The large sized dorsal vertebra is assigned to the taxon Epachthosaurus based on the following diagnostic characters which are autapomorphic for the above mentioned taxon: strongly developed intraprezygapophyseal lamina, accessory articular processes extending ventrolaterally from the hyposphene, and aliform processes which project laterally from the dorsal margin of the spinodiapophyseal lamina.The incomplete sacrum has five sacral vertebrae and a portion of the right ilium and pubis.These materials are included within Titanosauria and tentatively pertain to Epachthosaurus.The study of the above mentioned materials is important because it increases our knowledge of the relative abundance of the taxon Epachthosaurus in Ocho Hermanos ranch outcrops.Furthermore, we propose a set of characters which allow the expansion of the generic diagnosis of Epachthosaurus.