Lutraria angustior

Philippi, 1844

Description (shell):
Shell elongate, somewhat quadrate, anterior hinge line sloping more steeply than posterior; gaping at both ends. Umbones anterior to midline. Sculpture of numerous fine grooves, developing as fine ridges close to the margin; growth stages clear. Right valve with two cardinal teeth and a single, poorly developed, posterior lateral. Left valve with anterior two cardinal teeth forming a solid, forked structure, third thin and indistinct; and single, thin anterior and posterior laterals. Adductor scars and pallial line distinct; anterior adductor scar elongate, irregular, lower edge of pallial sinus largely fused with pallial line.

Up to 100 mm long.

Dull white or yellowish, periostracum pale yellowish brown. Inner surfaces white, glossy.

Animals burrow vertically into deep mud, the siphons reaching up to the surface.

In mixed soft substrata, offshore to about 50 m.

Uncommon in the North Sea, ranging south to the Mediterranean and West Africa (Distr. L. angustior).