(Gmelin, 1791)
Description (shell);
Shell thick, shallowly convex; obliquely oval. Sculpture of numerous (about 50) faint ribs, most conspicuous ventrally, concentrated on middle regions of shell and absent from areas adjoining anterior and posterior margins. Prodissoconch and first growth stages typically smooth and glossy. Growth lines clear. Each valve with two cardinal teeth, right posterior being considerably larger than right anterior. Right valve with two anterior and one posterior lateral; left valve with single anterior and posterior laterals, anterior being much larger than posterior. Inner surfaces smooth. Adductor scars distinct, pallial line less so; external ribs visible as grooves extending from margin to pallial line but fading rapidly beyond it (L. crassum-drawing).
Size:
Up to 70 mm long, as deep as its greatest length.
Colour:
Cream, light yellow to fawn, with blotches of pink, chestnut, or brown, particularly about the umbones. Periostracum greenish, thin. Inner surfaces glossy white tinted with pink, darkest close to margin (L. crassum; variation).
Animal:
Yellowish white in colour, the mantle is tinged with red and its edges are plain. The siphons are separated throughout their length but united at the base. It has a large and powerful foot, with a rough flesh-coloured coat.
Habitat:
Offshore, to the edge of the continental shelf, in sand and shelly gravel.
Distribution:
Ranges from Norway to the Mediterranean and West Africa (Distr. L. crassum).