(Pennant, 1777)
Description (shell):
Shell thin and brittle, elongate; dorsal margin practically straight, ventral margin curved. Anterior end rounded and upturned, posterior slightly truncate. Sculpture of fine lines, following the distinct growth stages. Left valve with a group of three projecting teeth: two cardinals, the posterior being broad and bifid, and posteriorly a single lateral. Right valve with two teeth, a single cardinal and a backwardly directed posterior lateral. Adductor scars and pallial line distinct; anterior adductor as long as ligament, posterior small and largely fused with the dorsal edge of the irregular pallial sinus (P. pellucidus-drawing).
Size:
Up to 40 mm long.
Colour:
White or cream, sometimes with dark markings; periostracum glossy, light yellow-brown or olive. Inner surfaces white.
Habitat:
In mixed fine substrata, offshore to about 100 m.
Distribution:
Distributed from Norway to north-west Africa (Distr. P. pellucidus).