Length 23 mm, height 16 mm, breadth 12 mm. Shell quadrate in outline, rather thin. Beaks a little ahead the center. Hinge line straight. Anterior margin round, continuous to straight ventral margin. Posterior portion higher than the anterior with obliquely truncated posterior margin. Surface with granulous radial ribs that become stronger posteriorly and some divided with a shallow groove. Periostracum brownish, hairy. Interior white. Cardinal teeth taxodont. Ventral margin crenulated in corresponding to external radial sculpture.
Distribution:
Southern Florida, Texas, Caribbean Sea and off Suriname. Shelf.