Upper Cenomanian-Turonian (Upper Cretaceous) ammonoids from the western Wadi Araba, Eastern Desert, Egypt

The Cenomanian-Turonian (C-T) successions (Galala and Maghra el Hadida formations) exposed on the footwalls of the slopes of the Galala plateaus in the Wadi Araba area in the northern part of the Eastern Desert, Egypt yielded a fairly rich and moderately to well preserved ammonoid fauna. In total, 24 taxa have been identified, 17 of which are systematically described herein. Four genera (Thomelites, Euomphaloceras, Wrightoceras, Eubostrychoceras) and four species (Euomphaloceras septemseriatum, Vascoceras pioti, Fagesia cf. peroni, Wrightoceras munieri) are recorded for the first time from Egypt. In addition, the taxonomy of ammonoids previously reported from these successions has been re-evaluated. The ammonoid fauna came from Upper Cenomanian as well as Lower and Upper Turonian (pars) strata; the Middle Turonian strata are barren of ammonoids. The presence of lower Upper Cenomanian ammonoids in the Galala Formation and mid-/upper Upper Cenomanian ammonoids in the lower part of the Maghra el Hadida Formation shows that the formational boundary between both units does not coincide with the C-T boundary as often reported in the literature. The palaeobiogeographic affinities of the taxa recorded classify the ammonoid assemblage as part of the (southern) Tethyan Vascoceratid Province during the early Late Cretaceous. (C) 2010 Elsevier Ltd. All rights reserved.