The snakehead Channa asiatica is a prized tonic fish in South China.

Channa asiatica belongs to the order Perciformes, suborder Anabantoidei, family Channidae, genus Channa. Common names: in Guangdong it is called qixing fish, shanhua fish, shanban fish, diancheng fish, chengxing fish, and xingguang fish; in Guangxi it is called xing fish and zhanggong fish; in Taiwan, China it is called youdai. English names: Snakehead, Chinafish. Its form resembles the spotted snakehead. The head is large, wide and flat, the snout short and bluntly rounded, the mouth large, and the nasal tubes thick, extending forward beyond the upper lip. The scales are relatively large, and the scales on top of the head are enlarged but irregular; the scales on the sides of the head are also relatively large. The bases of the dorsal and anal fins are long; the pectoral and caudal fins are both rounded; there are no pelvic fins. The body margins are black to grayish black, and the belly is grayish white. Behind the eye on the side of the head there are 2 black longitudinal bands extending to the operculum, and the upper band curves toward the base of the pectoral fin; on the sides of the body there are 7-9 chevron-shaped transverse bands with their pointed ends facing forward; at the base of the caudal fin there is 1 black eye-like spot, and around the spot there is a pearl-colored ring or 1 ring of pearl-colored bright spots; the whole body is covered with pearl-colored bright spots, and the dorsal and anal fins each have multiple rows of pearl-colored bright spots, especially conspicuous in males.

Channa asiatica is a eurythermal fish with strong adaptability. Its survival water temperature is 1-38°C, feeding water temperature is 12-32°C, growth water temperature is 13-30°C, and optimal growth water temperature is 15-25°C. It has the living habits of preferring darkness, liking to dig holes, dwelling in caves, living in groups, and cannibalism. It likes to inhabit mountain streams and also lives in rivers, ditches, ponds and other water bodies. It is fierce in nature and quick in movement, and is an animal-based omnivorous fish, feeding on fish, shrimp, aquatic insects and so on. Under artificial domestication conditions, it likes to eat compound feed and frozen fresh fish. The age at first sexual maturity is 2 winters, while artificially farmed fish reach it at 1 winter, and the relative fecundity is about 500 eggs. The reproductive period is from April to June, with the peak spawning period from May to July, and the breeding water temperature is 18-28°C. The parent fish have the instinct to pair up, build nests and protect the young. It is distributed in the various river systems south of the Yangtze River, and is relatively more common in the upper reaches. It grows relatively slowly and is not large in individual size, generally weighing about 250 grams; however, it is rich in nutrients, has tender flesh and a delicious taste, and also has medicinal value such as promoting muscle growth and invigorating blood circulation. People like it more than the spotted snakehead, and it sells well in South China, Hong Kong, China, Macao, China and Southeast Asia.