Maximum diameter 8 cm. The colour of the shell is variable, from near-white to black through brown, red and purple. It has about twenty ribs.
This is the common commercial scallop of the American Atlantic coast and is found in several varieties, of which another is the southern scallop (New Jersey to Florida). โOn clear, calm days the immature individuals of this species may often be seen in shallow water disporting themselves most gaily, skipping about and snapping their valves in great glee.โ (Augusta Foote Arnold.)