Mussels（Qingkou clam） , namely emerald mussels , also known as Rainbow . When dried, it becomes a “mussel”. Distributed in the southern part of the East China Sea and the coast of the South China Sea. The shell is larger, with a shell length of 13 to 14 cm. The shell is long, and the shell length is twice the shell height. The top of the shell is at the forefront of the shell, the beak. The dorsal margin is curved, and the abdomen margin is straight or slightly concave. The shell is thin, the surface of the shell is smooth, emerald green, the front part is often greenish brown, the growth pattern is fine, and the front end has a raised rib. The inner surface of the shell is porcelain white, or bluish, with pearl luster. There are 2 hinge teeth on the left shell and 1 on the right shell. The feet are soft and light yellow.