Shell large, thick, lather compressed and sub circular in shape with posterior margin nearly straight. Dorsal margin staight and shorter than the shell height with edentulous hinge. Outer surface lamellose with con- centric scales and radial rows of overlapping scales. color externally blackich gray with witish radial stripes and internally iridescent with black margins. this is the type species of genus and producing natural pearls. distribution: Vung Tau, Khanh Hoa, Phan Rang, Phan Ri, Con Son Island, ... Size: 70-120 mm.