Feeding traces on postcranial sauropod remains from Bajo de la Carpa Formation (Upper Cretaceous, Santonian), northern Neuquén Basin, Patagonia, Argentina

Abstract

Bite marks in non-avian dinosaur fossil records can constitute the best evidence of predator-prey interactions even if they are uncommon, ambiguous, or of uncertain origin. In this contribution, we present new evidence of feeding traces on an isolated sauropod element from Bajo de la Carpa Formation outcrops (Upper Cretaceous, Santonian), northern Neuquén province, Patagonia, Argentina. The specimen is composed of a partial dorsal vertebral centrum (MAU-Pv–CO–651; deposited at the Museo Municipal Argentino Urquiza, Rincón de los Sauces, Neuquén, Argentina). We tentatively refer it to an indeterminate titanosaur sauropod due to the presence of an opisthocoelic articulation and an internal pneumatic camellate condition. Three kinds of marks are preserved on the lateroventral face of the centrum: large and deep parallel marks, small and shallow longitudinal marks, and deep oval holes that we tentatively consider as punctures. These fossil marks can be considered to be feeding traces produced by a large-bodied carnivore to deflesh the bone and/or to obtain bone nutrients, probably during a single scavenging event. The marks and the punctures on the vertebral centrum can be referred to a theropod dinosaur due to their pattern and distribution. Viavenator exxoni (Filippi et al., 2016) represents the most likely trace-maker candidate among the several theropod and crocodile taxa present in the Bajo de la Carpa Formation fossil record. The fossil feeding traces reported here improve our knowledge about the feeding behaviour of large scavengers in the north of the Neuquén Basin, at least during the Santonian.