الفهرس 
ACKNOWLEDGEMENTS
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Abstract
The Campanian and Maastrichtian stages are very poorly documented time intervals in Africa’s record of terrestrial vertebrate evolution. Upper Cretaceous deposits exposed in southern Egypt, near the Dakhla and Kharga oases in the Western Desert, preserve abundant vertebrate fossils in nearshore marine environments, but have not yet been the focus of intensive collection and description. Our recent paleontological work in these areas has resulted in the discovery of numerous new vertebrate fossil bearing localities within the middle Campanian Quseir Formation and the upper Campanian-lower Maastrichtian Duwi Formation. Fossil remains recovered from the Campanian-aged Quseir Formation include sharks, rays, actinopterygian and sarcopterygian fishes, turtles, and rare terrestrial archosaurians, including crocodyliforms and some of the only dinosaurs known from this interval on continental Africa. The upper Campanian/ lower Maastrichtian Duwi Formation preserves sharks, sawfish, actinopterygians, and marine reptiles (mosasaurs and plesiosaurs). Notably absent from these collections are representatives of Mammalia and Avialae, both of Arabia. Non-marine vertebrates, including many crocodyliform clades, remain poorly documented from uppermost Cretaceous deposits of Africa. Recent exploratory fieldwork in the Upper Cretaceous (middle Campanian) Quseir Formation exposed around Dakhla Oasis (Western Desert of Egypt) has revealed new and abundant crocodyliform remains. In particular, materials of an enigmatic crocodyliform, represented by both cranial and postcranial remains, suggest the presence of a novel southern Tethyan crocodyliform fauna from northern Africa during the Late Cretaceous. Materials recovered of this taxon thus far include fragmentary portions of the skull and mandible, amphicoelous dorsal vertebrae, and fragmentary appendicular remains that referred to Wahasuchus egyptensis and isolated cranial and postcranial elements that referred to crocodyliforms. Wahasuchus egyptensis is distinguished by a number of unique features including a domed platyrostral skull; a strongly festooned lateral margin of the maxilla with two waves of tooth enlargement; a deep sculptured fossa at the base of the postorbital bar; a jugal with an anterior process that is at least three times broader than the posterior process; an orbital margin dorsally overlapping the lateral temporal fenestra; a supraoccipital with a distinct medial tuber and associated ventral fossa; and a robust straight dentary with contribution of the splenial to the symphysis. This new form suggests a potentially unique Late Cretaceous assemblage from northern Africa, markedly different from better-known Late Cretaceous crocodyliform assemblages of South America and Madagascar, or from earlier (pre-Turonian) deposits in Africa. This pattern may reveal a distinct regional fauna along the southern Tethys, or potential Cretaceous relationships with Eurasian neosuchian-dominated assemblages.