Found on clean sand, muddy sand, mud or muddy gravel from the middle to lower intertidal, sometimes subtidally. Usually live at salinities between 15 -35 psu but can tolerate salinities as low as 10 psu. The familiar edible cockle. Shell with 22-28 radiating ribs, crossed by conspicuous concentric ridges and may bear short, flat spines. Outer surface off-white, yellowish or brownish.
Growth lines are prominent.
Inner surface dull white, with a brownish or light purple stain on or about the posterior adductor muscle scar. The pallial line lacks a sinus. Both valves bear two cardinal teeth. In addition the right bear two anterior and two posterior lateral teeth while the left valve bears a single anterior and posterior lateral. Shallow grooves on the inner surface run from the notched margin, fading before reaching the pallial line.