Razor clam is a marine shellfish. Molluscs. There are two shells, which are narrow and long in shape, with egg-yellow outside and white inside. They live in coastal seawater and can also be cultured artificially, and the meat is delicious. There are SINONOVACULA constricta and SINONOVACULA constricta.

The two water pipes of Kun Kun are very developed. It keeps in touch with the seawater on the beach completely by relying on these two water pipes, sucks in food and fresh seawater from the water inlet pipe, and discharges waste and sewage from the drainage pipe. Sinonovacula constricta lives by digging holes in soft mud beach, and its latent depth varies with seasons: it is warm in summer and shallow; It is cold in winter, and it lurks deeply. Usually, the lurking depth is about 5 ~ 6 times of the body length, and the deepest can reach 40 cm, which is about 10 times of the body length.