Late Carboniferous macrofauna from Wadi Araba, Eastern Desert, Egypt, and their paleoecological implications

The Upper Carboniferous rocks at Wadi Araba are highly rich in macrofaunal content. The systematic description of these macrofauna reveals the identification of 34 species, 17 species of which are recorded for the first time from the Carboniferous rocks of Egypt, among them the trilobite Cummingella (C.) carringtonensis carringtonensis (Etheridge). Moreover, the paleoeclogic study on some crinoid and brachiopod specimens shows predation and commensal relations with some endo and epibionts fauna. The study presents also crinoidal infestation by Oxytoma (Palmoxytoma) cygnipes (Young and Bird) species, a relation which is recorded for the first time. Evidences of crushing or biting damages on some brachiopod shells that have been attributed to nautiloids or conchostracan arthropods are also reported. The microfacies study of the carbonate rocks in this area reveals the identification of five microfacies types indicating that the rocks were deposited in an environment ranging from restricted inner to outer shelf lagoonal environments with open circulation. The microfacies study indicates also the presence of two types of microorganisms, the filamentous microorganisms and the fossilized microbial carbonate communities, which played an important role in iron oxide precipitation and rock diagenesis. (C) 2011 Elsevier Ltd. All rights reserved.