Solid shell up to 2cm in length. Broadly oval in outline. Dirty white, light yellow or fawn in colour. Sculpture of up to 50 radiating ribs raised into small tubercles by concentric ridges. Periostracum fibrous and slight.
- Shell has up to fifty radiating ribs which combine with concentric ridges to give a knobly appearance
- Inner margin crenulate
Shallow burrower in sand, muddy sand and gravel. Feeds by filtering phytoplankton from the water.
Widely distributed. Common.Recorded from the North of Norway to Iberian Peninsula and the Mediterranean and the Black Sea.