Flounder, also known as toothfish, opilio, plaice, planktivorous fish, and migratory fish, inhabit shallow, sandy bottoms and prey on small fish and shrimp. They are particularly adapted to benthic life on the seabed. Due to their flattened body. The eyes are the same on the upward-facing side of the body, and the color of this side matches their surroundings well; the downward-facing side of their body is white. Flounder have extremely fine scales on the surface of their body. Flounder have only one dorsal fin, which extends from the head almost to the caudal fin. They live mainly in temperate waters and are an economically important fish in temperate seas. Flounder is a valuable seafood. It is called toothfish in fisheries. The body of the flounder is usually 25 centimeters to 50 centimeters long, and the largest flounder is 70 centimeters. Flounder will do short-distance cluster migration according to the change of seasons. Along the coast of China, turbot has a wide distribution. Fishermen in the Yellow Sea and Bohai Sea use bottom trawling nets to catch turbot. Fresh flounder can be eaten or canned. The liver of turbot can also be refined into cod liver oil