Abstract

The anatomy and phylogenetic relationships of the Upper Triassic theropod Zupaysaurus rougieri are reviewed. This taxon is represented by a nearly complete skull and fragmentary postcranial remains recovered from the Los Colorados Formation (Norian), NW Argentina. Originally, Zupaysaurus rougieri was considered a basal member of the Tetanurae, but its anatomy closely resembles that of the Coelophysoidea, supporting its nesting within this theropodan subclade. Thus reinterpreted, Zupaysaurus represents the first record of coelophysoids in South America. Phylogenetic analyses perfomed in this study depict Zupaysaurus as a non-coelophysid coelophysoid. Autopomorphic traits of Zupaysaurus include: maxillary-jugal ventral margin forming an obtuse angle in lateral view, tibia with a very deep and caudally open caudal fossa for the reception of an astragalar caudal process. Within the phylogenetic context outlined here, the derived features shared with Tetanurae (e.g. maxillary fenestra, caudally forked ascending ramus of the maxilla) are better interpreted as homoplasies rather than tetanuran derived features.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.