Pismo Clams are rare Pacific clams. They can only legally be caught when they are over 4 1/2 inches wide (11cm), which they reach when they are about 5 years old. They can grow up to 7 inches (18 cm.)
They are tender and sweet and considered a delicacy, and priced accordingly.
Part of the clam can be eaten raw (the connector muscle), but the rest of it is normally cooked. Remove and discard the stomach first.
Named for Pismo Beach, California.