Description of a New Genus of Radiolitidae (Bivalvia, Hippuritida) with Canals in the Calcitic Shell Layer

Abstract

The species Radiolitella pulchellus (Vidal 1876) from Campanian-Maastrichtian of Spain (provinces of Lleida and Barcelona) and France (Dordogne) is revised and re-described. The genus Radiolitella gathers all the Radiolitidae where the floors formed by the growth lamellae disappear and the cells take the appearance of canals. R. pulchellus is the only taxon with canals in the calcitic layer of the left valve while canals of the other Radiolitella species are found on the right valve. This major difference suggests that the genus Radiolitella should be redefined with species having canals on the left valve moved to a new genus. A new species is proposed based on an unpublished specimen from the Toucas collection which belongs to them as a group.