It is shaped like an intestine, so it is also known as the sea intestines, sand intestinal worms, long cylindrical, body length of about 10-20 cm, and all naked and hairless, the body wall longitudinal muscles into bundles, each ring of muscles staggered arrangement, the formation of a square lattice pattern.

Genera of the starworm family square lattice starworm. Sandworms, its name is not beautiful appearance is not elegant, but its nutrition, flavor and medicine and therapeutic value are no less than other valuable seafood treasures, and thus known as the "beach sausage" reputation. The distribution area of the starfishes is mainly on the mudflats along the coasts of Fujian, Guangdong, Guangxi, Hainan and Taiwan. Because of the quality of the growing environment is very sensitive, once the pollution can not survive, and therefore has the name of "environmental symbols of biological". Residents of southern Fujian will be sandworm boiled into a thick soup, cooled into a jelly, called "soil bamboo shoots jelly".