A SUPPOSED GONDWANAN OVIRAPTOROSAUR FROM THE ALBIAN OF BRAZIL REPRESENTS THE OLDEST SOUTH AMERICAN MEGARAPTORAN

ALEXIS M. ARANCIAGA ROLANDO; BRISSÓN EGLI F.; MARCOS SALES; AGUSTÍN MARTINELLI; MARTIN EZCURRA; JUAN CANALE

CRETACEOUS RESEARCH (PRINT)

ACADEMIC PRESS LTD-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2017 vol. 84 p. 107 - 119

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 described as an oviraptorosaur, but it is here re-interpreted as the oldest megaraptoran of South America. The phylogenetic relationships of SMNS 58023 were tested quantitatively for the first time including it the two most comprehensive phylogenetic data sets focused on non-maniraptoran theropods ?including megaraptorans. The Brazilian specimen was consistently found as a megaraptoran in both analyses because of the presence of sacral centra longer than tall, absence of a median transverse constriction of sacral centra, and the morphology and position of sacral pleurocoels. SMNS 58023sheds light on a region of the body that is poorly known in megaraptorans and pulls back the temporal range of the clade in South America. This re-interpretation reinforces the absence oviraptorosaurs in Gondwana.