Irregularly elongated oval to rounded trigonal with only slightly undulating or straight margins, deeply cupped, with flat upper right valve fitting well into deep lower left valve, moderately compressed, solid, grayish white, with irregular commarginal lamellations; interior glossy white with purple round muscle scar, margin smooth (chomata absent), anal funnel absent. Eastern Canada to Florida, Bermuda, West Indies, Gulf of Mexico, South America (French Guiana, Brazil). Length 10 mm (to 150 mm). Compare Crassostrea rhizophorae, which has an elongated purple adductor muscle scar, and Ostrea equestris, which is greenish internally. Note: The habitat of this species is estuarine.