The shoulder has a strong carina or ridge which is weakly beaded in the early whorls. Common in shallow, sandy areas. Left-handed specimens are very rare. One to 2 inches in size, irregularly oval, smoothish, thin but strong. Some with a slivery sheen.
Specimens buried in mud become blackened.
Very commonly attached to logs, wharfs and boats. The round, calcified base of the byssus from formerly living specimens may remain attached to stones and other shells. Lunule heart-shaped, with minute vertical threads. A very common, shallow-water species in the southeast United States. Beach worn specimens have a cancellate sculpturing.