Littleneck clams range from the Aleutian Islands to Baja California, though they are only abundant north of Oregon. Commonly found in bays and estuaries along the coast of British Columbia, littleneck clams live at low- to mid-intertidal depths, burrowing up to 15 centimetres into the beach.

Littleneck clams are round in profile, with concentric rings (which can be used to determine age) and radial ribs on the surface of the shell. Their colouration varies from white, off-white or cream, mottled with brown, to grey. Littleneck clams have separate sexes and a re broadcast spawners. Littleneck clams grow to a maximum size of 70 millimetres shell length and live to a maximum age of approximately 14 years.