Irregularly oval to quadrangular, often distorted, posterior end elongated and truncated, slightly gaping anteriorly and posteriorly, with byssal notch at anterior end of ventral margin, moderately compressed, thin-walled, translucent pearly with coarse, crinkly, thin, light brown periostracum, with weak, raised radial threads and coarse commarginal growth lines near margin, early part of valves with rasplike surface and radiating lines of small pimples; interior margin smooth. North Carolina to Florida, Bermuda, Bahamas, West Indies, Gulf of Mexico, Caribbean Central America, South America (Colombia, ? Brazil). Length 19 mm (to 23 mm). Note: The relationship to Entodesma brasiliensis (Gould, 1850), often considered a synonym, needs further study.