Thin, fragile, shell up to 2cm in length. It is usually white, pink or red in colour. The surface of the right valve is relatively smooth while the left has numerous radiating ribs.
- Anterior ears are three or four times as long as posterior
- The sculpture of the valves is different; right vale is smooth while the left has numerous radiating ribs
- The ribs are covered with projecting scales and crossed by irregular raised lines
Lives on hard ground where it feeds by filtering phytoplankton
RareDistributed from northern Norway to the Iberian Peninsula and into the Mediterranean.