Porfiri, J. & Calvo, J. (2006) A new record of Carnotaurine (Theropoda: Abelisauridae) from the Upper Cretaceous of Neuquén, Patagonia JVP 26(3) Abstracts pp.111-112

We report a new pelvis of a Carnotaurinae abelisaur from the “La Invernada” locality, placed 35 km Southwest of Rincón de los Sauces city, Neuquén, Argentina. The pelvis (MUCPv 1125) was unearthed from the Bajo de la Carpa Formation (Santonian) of the Neuquén Group. This pelvis is composed of both ilia, ischia and pubis, and 6 sacral vertebrae.

As in adult ceratosaurs, all pelvic elements are fused. In MUCPv 1125 the ilium presents the ventral margin of the preacetabular blade projected downward, which is more
expanded dorsoventrally than the postacetabular blade. The pubis has the obturator foramen placed proximally and shows a small pubic foot that is expanded anteroposterioly. The pubis apron expands until the mid-half of the shaft. The opposing ischia contact on the proximal end and show a slight foot-like expansion. Carnotaurinae (middle Aptian to Maastrichtian) includes: Genusaurus, Majungatholus, Rajasaurus, Pycnonemosaurus and the Carnotaurini (Aucasaurus + Carnotaurus + unnamed specimen from Bajo Barreal Formation).

The pelvis of “La Invernada” shows morphological features observed only in the Carnotaurinae clade such as the elongated and low ilium with straight dorsal border, acute ventral notch on the preacetabular blade and posterior border of the postacetabular blade of the ilium with a marked concavity forming a dorsal and a ventral projection, and JVP 26(3) September 2006—Abstracts 111A therefore is here regarded as a member of the Carnotaurinae. MUCPv 1125 resembles Genusaurus, confirming that the latter is also a member of that clade. The discovery of this pelvis of a Carnotaurinae increases the knowledge of this group and suggests that those theropods played a major as predators during the Upper Cretaceous of Patagonia.