Habitat: it lives in the infralittoral zone in different habitats, mainly along rocky coasts, fixed by its byssus into ravines, under stones and at the base of algae. Plenty of it inside the formations “trottoir". Distribution: rather common all over the Mediterranean.
Notes: shell solid, equivalve, inequilateral, oval in outline, round on the sides, valves rather convex. Umbo protuberant and placed posteriorly. Surface crossed by very thin concentric striae, smooth internally and a little bit pearly. Periostracum yellowish in colour, internal margin of the valves smooth. Hinge with two single lateral teeth, anterior and posterior ones, in the right valve, while in the left valve there is one small cardinal tooth below umbo, besides the two lateral ones. Ground pink, more or less vivid in colour, sometimes bright red wine but there can be found specimens either yellowish or uniform dirty white (variant pallida Jeffreys. 1864; alba Sowerby). As far as the variety major B.D.D., 1892 is concerned, its specimens can reach 5 mm in width.
Outline and peculiar colour pattern of this species make it easily recognizable from the other small bivalves of the Mediterranean. The juvenile specimens, about 1 mm in width, have no protuberant umbo and they are more roundish in outline. The adult specimens average measures are around 3 mm in width.