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<em>Atrina fragilis</em> (Pennant, 1777)
RareDistributed from Britain south to the Iberian Peninsula
Lives with pointed end buried in bottoms of mud to gravel where it attaches itself with byssus threads. Tend to be quite a gregarios species
- Very distinctive triangular outline
- Two adductor muscle scars
Brittle shell up to 30cm in length. It is light to dark brown in colour both inside and outside but inside is glossy. The surface is sculptured with concentric lines and 8 to 12 radiating ribs. There are no teeth on the hinge.