Defense title: "A new crocodylian from the Eocene (Ypresian) of Wyoming (Greater Green River Basin, USA) and the origins of Longirostres"

The Eocene rocks of western North America have produced a diverse assortment of fossil crocodylians and their extinct close relatives, with a number of distinct species currently recognized. Examination of fossil material from the Bridger Formation of Wyoming has revealed a new, previously unrecognized species of crocodylian that further expands the biodiversity of this group in western North America approximately 49-million-years-ago. This new species is distinguishable from other similar fossil crocodylians on the basis of various morphological features, including the sutural relationships of the skull bones and the presence of prominent ridges on the snout. Analyses of a new phylogenetic dataset looking at the evolutionary relationships of the new species recover it in a relatively derived position compared to other Eocene North American crocodylians and close to the origins of some major modern crocodylian lineages (e.g., Gavialoidea, Crocodylidae). This new species and the results of the phylogenetic analyses highlight the importance of North American Cretaceous-Paleogene fossils in understanding the early evolution of Crocodylia and suggests the potential for additional undescribed fossil species.