A supposed Gondwanan oviraptorosaur from the Albian of Brazil represents the oldest South American megaraptoran

ARANCIAGA ROLANDO, ALEXIS M.; EGLI, FEDERICO BRISSÓN; SALES, MARCOS A.F.; MARTINELLI, AGUSTÍN G.; CANALE JUAN IGNACIO; EZCURRA, MARTÍN D.

CRETACEOUS RESEARCH (PRINT)

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2017

0195-6671

A specimen composed of a partial sacrum articulated to two anterior caudal vertebrae and an ilium(SMNS 58023) from the Lower Cretaceous (Albian) Santana Formation of Brazil was originally describedas an oviraptorosaur, but it is here re-interpreted as the oldest megaraptoran of South America. Thephylogenetic relationships of SMNS 58023 were tested quantitatively for the first time including it in thetwo most comprehensive phylogenetic data sets focused on non-maniraptoran theropods eincludingmegaraptorans. The Brazilian specimen was consistently found as a megaraptoran in both analysesbecause of the presence of sacral centra longer than tall, absence of a median transverse constriction ofsacral centra, and the morphology and position of sacral pleurocoels. SMNS 58023 sheds light on a regionof the body that is poorly known in megaraptorans and pulls back the temporal range of the clade inSouth America. This re-interpretation reinforces the absence of oviraptorosaurs in Gondwana.