Genus Periploma Schumacher, 1817

Periploma Schumacher, 1817 . Type species (by monotypy): Periploma inaequivalvis Schumacher, 1817, = Corbula margaritacea Lamarck, 1801 . Recent, Florida.

Shell ovate to subquadrate, thin, inequivalve; right valve more inflated, overlapping left; anterior end rounded; posterior end truncate; umbones opisthogyrate, with radial fissure; sculpture granulate or pustulate; hinge plate narrow, with large chondrophore in each valve supported by rib or clavicle; lithodesma usually present; interior subnacreous.

The genus, known from the Cretaceous, is primarily temperate and tropical in distribution. The name is derived from the Greek peri–, from, and –plyma, dirty water; the gender is neuter.