1. River crabs are not seafood.

2. River crabs are also called "crabs" and "hairy crabs". The cephalothorax formed by the combination of the head and chest is square-shaped and hard in texture. There is a pair of eyes on the front of the body, and two pairs of very sharp crab teeth on the sides. The frontmost pair of appendages of the crab are called chelipeds, and the surface is covered with hairs; behind the chelipeds are four pairs of walking legs, with flat and long sides; the abdominal limbs have degenerated. The male and female river crabs can be distinguished by their abdomen: the abdomen of the female is round and the abdomen of the male is triangular.

3. The river crab is a large crustacean with a body divided into 21 segments. Since the head and chest segments heal each other, the whole body is divided into two parts, the cephalothorax and the abdomen. The back of the adult crab is dark ink, and the average length of the head and breastplate is 7cm and 7.5cm wide.

4. River crabs often live in burrows on the mud banks of rivers, lakes and swamps. They are active at night and feed on fish, shrimps, animal carcasses and grains. They often migrate to estuaries out to sea to lay eggs every autumn. They hatch from March to May, develop into young crabs, and then swim back up the river. Its meat is fresh and tender, and it is a popular food.