Circomphalus casina
Distribution and status
Common. Found from the south of Norway to the Iberian Peninsula and into the Mediterranean.
Ecology and behaviour
Shallow burrower in bottoms of sand, muddy sand, gravel and shell gravel. Feeds by filtering phytoplankton from the water.
Similar species
- Venus verrucosa but concentric ridges are not broken into wart like sculpturing
- Clausinella fasciata lacks the prominent concentric ridges
Key identification features
- Inner margin of shell crenulate
- Prominent concentric ridges on shell surface
- The anterior and posterior margins on the outside of shell do not possess wart like spines.
Taxon version key
[NBNSYS0000174564]
Sort order
10910
Taxonomic group
Marine bivalve
Solid shell up to about 5cm long. Dirty white to pale fawn in colour, sometimes with red brown rays. Pallial sinus small and triangular. Sculpture of concentric ribs which are sometimes broad and flattened and others sharp and foliaceous. Periostracum, if present, is chestnut brown and strongest at the edge of the shell.