New carnivorous dinosaur from the Late Cretaceous of NW Patagonia and the evolution of abelisaurid theropods

CANALE, JUAN IGNACIO; SCANFERLA, CARLOS AGUSTÍN; AGNOLÍN, FEDERICO LISANDRO; NOVAS, FERNANDO EMILIO

NATURWISSENSCHAFTEN

Springer

Año: 2009 vol. 96 p. 409 - 414

0028-1042

Abstract A nearly complete skeleton of the new abelisaurid Skorpiovenator bustingorryi is here reported. The holotype was found in Late Cenomanian-Early Turonian outcrops of NW Patagonia, Argentina. This new taxon is deeply nested within a new clade of South American abelisaurids, named Brachyrostra. Within brachyrostrans, the skull shortening and hyperossification of the skull roof appear to be correlated with a progressive enclosure of the orbit, a set of features possibly related to shock-absorbing capabilities. Moreover, the development of horn-like structures and differential cranial thickening appear to be convergently acquired within Abelisauridae. Based on the similarities between Skorpiovenator and carcharodontosaurid tooth morphology, we suggest that isolated teeth originally referred as post-Cenomanian Carcharodontosauridae most probably belong to abelisaurids.