Habitat: it lives in low depths on muddy bottoms near Posidonia oceanica and Zostera marina. It can bury itself into mud for some decimetres too.
Distribution: it can be found all over the Mediterranean, but never common.
Notes: unmistakable shell, stretched, valves inequilateral, light, brittle, open at the two ends, hinge small and teeth missing, broad callosity inside valves. Umbo, small and not much clear, placed in the upper part, roundish in form. Dorsal margin straight, not much convex ventrally. Periostracum smooth, thin but solid and adherent, bright, brown in colour, protuding quite a lot from margins, making some fringes. Some radial lines, not much prominent, lighter, starting from umbo up to the valves margin. Pearly inside, muscle scars quite evident. The varieties minor Monterosato, 1884 and major B.D.D., 1898 are recognizable due to the different sizes only. Juvenile specimens have a lighter colour pattern and they are more roundish in outline. The adult specimens average measures are around 35-40 mm in length.