Clam (Chinese pinyin: gé lí), also known as Meretrix meretrix, Meretrix meretrix, Shih Tzu, Clam and Flower Shell, is a general term for bivalve mollusks, some of which are edible.

2 shells, thick, slightly quadrangular. The length of the shell is 36 ~ 48 mm, the height is 34 ~ 46 mm, and the width is about 4/5 of the height. The left and right shells are equal. The top of the shell is slightly bent forward, located in the middle of the rear edge of the shell, slightly forward. The middle part of the shell surface expands, and the front, back and belly edges contract sharply, making the front and back edges form edges, crescent moons and rafters. Heart shape. The growth line on the shell surface is obviously thicker, forming an uneven concentric ring. A shell has a shell skin, with a white or lavender top, yellowish brown near the ventral surface, and a narrow black belt at the ventral edge. The inside of the shell is grayish white. The hinge is very wide.