Revision of the echinoid genus Micropedina Cotteau, 1866 and description of a new species from the upper Cenomanian of Egypt

Currently, the genus Micropedina contains seven species and a single variety, with records from the lower Upper Cretaceous of Europe (Portugal, Spain), North Africa (Algeria, Tunisia and Egypt), West Africa (Nigeria), the Middle East, India and the Americas. In Egypt, a total of five species is known to date. Based on the oblique arrangement of pore pair triads in each compound ambulacral plate, three species cannot be assigned to the genus any longer; these are ‘M.’ sphaeroides, ‘M.’ rotularis and ‘M.’ bipatellis. Using ambulacral plate compounding, two species are valid, M. olisiponensis and M. cotteaui, in addition to a variety which is here elevated to species rank, M. gongilensis, and a new species erected herein, M. simplex. Three species are described from the upper Cenomanian Galala Formation of north Wadi Qena (Northeastern Desert, Egypt) namely M. olisiponensis, M. cotteaui and M. simplex sp. nov. The palaeobiogeography, functional morphology and palaeoecology of the genus are discussed.