Mesozoic continental vertebrates with associated palynostratigraphic datesfrom the northwestern Ethiopian Plateau

The East African Rift separates the northwestern and southeastern Ethiopian high plateaus, which are capped by massive Cenozoic volcanics overlying th ick deposits of marine and nonmarine Mesozoic sediments. During geological mapping projects of the 1920s-1930s, a few Mesozoic vertebrate fossils were found on the southeastern plateau. in contrast, beginning in 1976, and the n from 1993 to the present, paleontological field work in the Abay (Blue Ni le) River gorge along the eastern edge of the northwestern plateau resulted in the discovery of fossil chondrichthyans (Priohybodus, Hybodus, Rhinobat os), osteichthyans (Lepidotes, cf. Pycnodus), dipnoans (Asiatoceratodus), c helonians (Pelomedusidae, Plesiochelyidae, Pleurosternidae), crocodylians ( Goniopholis), dinosaurs, (cf. Acrocanthosaurus Hypsilophodontidae), pollen and other microfossils documenting a coastal biota in part, if not entirely , of latest Jurassic (Tithonian) age. These fossils include new biogeograph ic records for Africa and document biostratigraphic range extensions. The E thiopian Mesozoic fauna adds to the growing evidence of limited interchange of vertebrates between Africa and Western Europe during the transition fro m the Jurassic into the Cretaceous.