Comprehensive Description

The Amethyst Gem Clam (Gemma gemma) is a tiny, somewhat triangular clam (usually less than 3mm) with a smooth, glossy shell. The inner shell has a finely scalloped margin (visible with a hand lens). Shell color is whitish or gray, often tinted with purple. (Morris 1973; Gosner 1978; Kozloff 1993) This clam is an Atlantic species introduced into Pacific waters. It lives in soft mud and is therefore found on muddy beaches. The short siphons never extend more than a few millimeters beyond the end of the shell. (Narchi 1971)