Ark-Shell

ark-shell the name given to bivalves of the family Arcidae. The double shell, when viewed from the end, looks something like a decked ship (or Noah’s ark). Some ark-shells are attached by a byssus, like that of the mussel, to a substrate, but others are unattached burrowers. Arca noae is a Mediterranean species which is sometimes eaten raw, but is better in the Ligurian dish Pasta con le zampe (zampe being the Ligurian name for ark-shells).

Ark-shells of tropical waters, in the genus Anadara, include a very large one, A. senilis, a W. African species which is almost globular in shape and may measure 14 cm (6.5") in diameter. A. granosa, the principal species of SE Asia, is only half that size. Scapharca inaequivalis, another species of the Indo-Pacific region, is markedly asymmetrical. All these species are known as ‘bloody cockles’ or ‘bloody clams’ because their flesh is red and they exude a red liquid, being possessed of the red blood pigment haemoglobin. This deters some people from eating them, although they should be valued as a good source of iron.