Brittle shell up to about 2.5cm in length. Colour white or pink often with patches/rays of purple or red. Inside similarly coloured. Sculpture of fine concentric ridges and up to about 20 sharp ridges running towards the hind margin.
Key identification features
- No lateral teeth
- About 20 ribs radiating from the umbones to the back of the shell
- Slightly gaping at each end
Similar species
Ecology and behaviour
Burrows in muddy or fine sand
Distribution and status
Not common
North Sea to the Iberian Peninsula and into the Mediterranean