Mussel aliases: Hewai, River Clam , Bird Shell, Gala (Northeast Dialect), Sao Gala (Shan Dongfang Dialect), etc. Mollusca, Lamellibranchia (Lamellibranchia) mussels. Pearl clam family. Subfamily Anodonta. Anodonta. Generic term for shellfish. Distributed in Asia, Europe, North America and North Africa. Most of them can naturally form pearls in the body. The shape is oval or oval. Thin shell. fragile. The two shells swell, sometimes with rear wings on the back. The top of the shell is wide and slightly raised, located in the middle or front of the back edge. The surface of the shell is smooth, with concentric growth lines or green radiation from the top of the shell to the ventral edge. The glued part is narrow and has no teeth. Axe foot is well developed. Dioecious. Edible meat is also a natural bait and feed for fish and poultry. Some species can be used as freshwater breeding pearls.