soft-shelled clam Mya arenaria, an edible bivalve found on both sides of the N. Atlantic, is greatly appreciated in Canada and the USA but less popular in Europe, where its range extends only as far south as the English Channel. It is large (up to 15 cm/6") and has a brittle shell which gapes permanently at each end. Even so, it can survive for a long time out of water, and even without oxygen, so can be marketed in good condition. Its double siphon is long, accounting for an alternative common name, long-neck. (A third name, steamer, is bestowed because it is judged to be particularly suitable for steaming. There is no obvious explanation for the Irish names maninose, nannynose, and brallion; nor is it clear why it has been called old maid in England.)
