Taxonomy and paleobiogeography of the Maastrichtian cephalopods from the Abu Monqar-west Dakhla stretch, Western Desert, Egypt

Abstract

ABSTRACT The Maastrichtian sedimentary succession in the Abu Monqar-west Dakhla stretch yields rare cephalopod content. Six cephalopods, including three nautiloids and three ammonoids, are described in detail and identified. Two new species of nautiloids are erected from the study area; these are Angulithes monqarensis nov. sp. and Anglonautilus hewaidyi nov. sp. The ammonoid Sphenodiscus lobatus (Tuomey) is firstly recorded from the Maastrichtian rocks of Egypt. Paleobiogeographically, Pachydiscus (P.) neubergicus has a wide geographic distribution within the Tethyan and Boreal realms. Sphenodiscus lobatus appeared earlier in the late Campanian of North America and then migrated through shallow environments to the Southern Tethys. The Anglonautilus appeared earlier in the Hauterivian age in the Northern Tethys and then migrated into Southern Tethys, Northern America, and Asia. The distribution of Baculites ovatus at the Southern Tethyan Province is chiefly controlled by the prevailed palaeoecological factors.