Middle-upper Cenomanian echinoids from north Wadi Qena, North Eastern Desert, Egypt

Abstract

Two Upper Cretaceous (middleeupper Cenomanian) sections located at the northern part of Wadi Qena were measured and their echinoids were collected carefully bed by bed. This area is abnormally rich in echinoids where their diversity is high and also many species are abundant. Twenty-three echinoid species (10 regular and 13 irregular) referred to twelve genera have been identified and taxonomically described. Two new species are established: Pedinopsis hemisphaerica and Phymosoma elqotti. The taxonomic rank of two species is changed. Three species, which are described from the Cenomanian of Algeria and Tunisia, are new records from Egypt. Phymosoma major Coquand, which is common in the Turonian of North Africa and south Europe, is recorded here in the Late Cenomanian for the first time. The echinoid Anorthopygus Cotteau, 1859 and its species are revised. Three echinoid assemblage zones are delineated in each of the two studied sections. They are compared to other macro-faunal assemblage zones in the Cenomanian at different parts in Egypt. The palaeobiogeography of the echinoids in the present study is discussed.