Margaritariidae, New Family (Pelecypoda) and Description of Two New Species

Abstract

The new family Margaritariidae is proposed for the genus Margaritaria Conrad, 1849, of which the type, and previously only known species, is Pholadomya abrupta Conrad, 1832. This species, described from the upper Miocene deposits at Yorktown, Va., has been reported from southern Maryland to South Carolina in beds of middle and (mainly) upper Miocene age. The southern limit of its range is here extended to Collier County, Florida. Two new species are described: M. inexpectata from the upper Eocene Moodys Branch Marl, near Montgomery, Louisiana, and M. gardnerae from the Miocene Shoal River Formation of the Alum Bluff Group in Walton County, Florida.