Appendicular osteology of Skorpiovenator bustingorryi (Theropoda, Abelisauridae) with comments on phylogenetic features of abelisaurids

Abstract

Skorpiovenator bustingorryi is a derived abelisaurid theropod represented by a fairly complete skeleton from the Late Cretaceous sedimentary beds of north-western Patagonia. Although some features were described in the original paper, mainly related to the skull, the appendicular anatomy remains undescribed. The aim of the present contribution is to provide a detailed description and analysis of the available appendicular bones, including comparisons with other ceratosaurian theropods close to Skorpiovenator. In this way, new autapomorphies emerged to further distinguish Skorpiovenator from its relatives. Furthermore, a comprehensive phylogenetic analysis was performed and several characteristics of the hind limb, in particular some of the autopodium, resulted in the identification of new apomorphic traits for Ceratosauria and Abelisauridae. These features might prove to be useful for future phylogenetic analyses and may help to resolve the still confusing and debated internal relationships of abelisaurid theropods.

Keywords:

• Ceratosauria
• hind limbs
• pelvic girdle
• phylogeny
• Cretaceous
• Patagonia

Acknowledgements

We are grateful to Jorge O. Calvo, Martín Ezcurra, Rodolfo Coria, Carlos Muñoz, Leonardo Filippi, Eduardo Ruigómez, Daniel Brinkman, Michael Brett Surman, Carl Mehling and Mike Getty for allowing access to specimens under their care. We thank M. Motta and M. Aranciaga-Rolando for their useful comments on an early draft of the manuscript. Special thanks to Oliver Rauhut, Diego Pol and Adam Marsh who shared photos of Elaphrosaurus, Eoabelisaurus and Dilophosaurus. Special thanks to Roberto Galeano who found the referred specimen of Skorpiovenator and to the Municipalidad de Villa El Chocón for logistical support. Also, we want to thank the Editor-in-Chief Paul Barrett, the Associate Editor Victoria Arbour, Thiago Marinho and an anonymous reviewer for their comments which improved this manuscript. The present contribution was funded by a CONICET doctoral scholarship granted to MAC.

Supplemental material

Supplemental material for this article can be accessed here: https://doi.org/10.1080/14772019.2022.2093661.

Associate Editor: Victoria Arbour