The red clam is not a hairy clam. The hairy cockle is a shellfish belonging to the family Trichodermaidae. The shell is medium in size, 40-50 mm long. The shell is thick, double-shelled, slightly angular at both ends of the dorsal side, the front end of the ventral edge is rounded, and the rear end is slightly extended. Usually the two shells are of different sizes, with the right shell being slightly smaller, the top of the shell protruding and curling inward, and the position is biased ahead. Red clams, also known as Kui clams, belong to the class Valelabranchidae and the family Clamidae. The shell is large and thick, the left and right shells are equal, oblique oval, and extremely expanded.

The red clam is not a hairy clam. The hairy cockle is a shellfish belonging to the family Trichodermaidae. The shell is medium in size, 40-50 mm long. The shell is thick, double-shelled, slightly angular at both ends of the dorsal side, the front end of the ventral edge is rounded, and the rear end is slightly extended. Usually the two shells are of different sizes, with the right shell being slightly smaller, the top of the shell protruding and curling inward, and the position is biased ahead. Red clams, also known as Kui clams, belong to the class Valelabranchidae and the family Clamidae. The shell is large and thick, the left and right shells are equal, oblique oval, and extremely expanded.