Balanoff AM

Introduction The bird-like theropod dinosaur Halszkaraptor escuilliei is a based on an almost complete skeleton from the Upper Cretaceous of Mongolia (Cau et al., 2017). Compared to other theropods, Halszkaraptor shows several unusual features, supporting the institution of a new lineage of Dromaeosauridae, the halszkaraptorines (Cau et al., 2017; Cau & Madzia, 2018; Agnolin et al., 2018), and suggesting a semiaquatic bauplan able to exploit both terrestrial and aquatic resources.

Introduction The theropod dinosaur Allosaurus is certainly one of the best-known dinosaur taxa for scientists and the general public alike. It was first described on the basis of a fragmentary specimen from the Late Jurassic Morrison Formation by Marsh (1877).

We use Romerian orientational descriptors (i.e., anterior, posterior) rather than standardized terms (i.e., cranial, caudal). Given the lack of a standardized terminology for sauropod skull bones and their various processes, we follow Wilson et al. (2016) in employing morphological and orientational descriptors for cranial element processes, favoring morphological descriptors where it is convenient to do so.