What varieties of snakehead fish are there? An introduction to common snakehead varieties

Scientific name: Channa Striatus

Malay names: Haruan, Aruan, Ruan, Taman Paya.

English name: Striped Snakehead.

Common names: striped snakehead, snakehead murrel.

Other names: black fish, cai fish, wu bang, spotted snakehead, snakehead fish, xiao fish, mo tou fish, etc.

The snakehead is a valuable freshwater economic fish of the family Channidae, notable for its large size, fast growth, high yield and high economic value.

I. The economic value of the snakehead

The snakehead is a valuable economic fish of the family Channidae, notable for its large size, fast growth, high yield and high economic value. Local names for the snakehead include: black fish, cai fish, wu bang, spotted snakehead, snakehead fish, xiao fish, mo tou fish and others. The snakehead is a freshwater fish of relatively high economic value, and a premium health food that is fully nutritious and has delicious flesh.

The snakehead has few bones, with an edible rate of 63%. In southern China, especially in Guangdong, Guangxi, Hong Kong, China and Macao, China, the snakehead has always been regarded as a precious tonic for recovery after illness and for those with a weak constitution. Guangdong's famous "snakehead and Ge Cai soup" is much loved by the general public. The snakehead has strong adaptability, grows rapidly and is easy to transport. In recent years, with the development of the domestic breeding industry and the needs of foreign trade, the snakehead has gradually become a special breeding species with strong demand in both production and sales, and snakehead breeding technology has attracted widespread attention and importance.

II. The biological characteristics of the snakehead

The snakehead belongs to the class Osteichthyes, order Perciformes, suborder Anabantoidei, family Channidae, genus Channa. At present, the main varieties bred in China are Channa argus, Channa maculata and their hybrids.

(I) Morphological characteristics

1. Morphological characteristics of Channa argus. The front part of the body is cylindrical, and the rear part is laterally compressed; the body length is generally 25-40 cm. The head is long, slightly flat and depressed at the front, and slightly raised at the rear. The body color is grayish black, the back and the top of the head are darker, the belly is pale white, the sides of the body each have irregular black patches, and the top of the head has 2 rows of black stripes. The dorsal fin is very long, almost connected to the caudal fin, with no hard spines, starting above the base of the pectoral fin. The pelvic fins are short and small, the pectoral fins are round, and the tips of the fins extend past the middle of the pelvic fins. The anal fin is shorter than the dorsal fin, the caudal fin is round, and its end does not reach the anus. The anus is located immediately in front of the anal fin. The whole body is covered with medium-sized cycloid scales, and the top of the head is covered with irregular scales. The lateral line is straight, with a small bend above the anus, shifting down 2 rows of scales, located in the middle of the side of the body, and extending back to the base of the tail. Fishermen in the Pearl River Delta region habitually call it "two-lake snakehead". The flesh has a relatively strong fishy smell.

2. Morphological characteristics of Channa maculata. The body length is generally 20 cm, and the body weight is 500-1000 g. The body is nearly cylindrical, and the caudal peduncle is thick and short. The head is long, the snout is short and slightly flat and depressed. The bases of the dorsal fin and anal fin are very long, with no hard spines. The pectoral fins are round, and the pelvic fins are small and located anteriorly. The caudal fin is round. The body is blackish gray, the belly is grayish white, and there are many irregular black spots of varying sizes; the black spots on the top of the head are in a "one-eight-eight" shape. It is habitually called "two-Guangs snakehead", and its flesh has no fishy smell when used in soup.

3. The main differences between Channa maculata and Channa argus. Channa argus has a longer body, while Channa maculata has a shorter body; the top of the head of Channa argus has a seven-star-shaped stripe pattern, while the stripe pattern on the top of the head of Channa maculata resembles the three characters "one-eight-eight". In addition, the head of Channa argus is more pointed and more snake-like.

4. Hybrid fish. Using Channa argus from other regions (Shandong, Hunan, etc.) as the male parent and Guangdong Channa maculata as the female parent, a first-generation hybrid was bred. This hybrid grows quickly, reaching a body weight of about 1 kg in 3 months, and has the characteristics of strong stress resistance, tender flesh and delicious taste. In the Pearl River Delta region, Channa maculata is commonly called "Hong Kong breed", Channa argus is commonly called "Hunan fish", and the first-generation fish produced by crossing the former two snakeheads is the "hybrid".

(II) Living habits

The snakehead is a bottom-dwelling fish, usually inhabiting still water or slightly flowing water with dense aquatic plants and soft bottom mud. It is found throughout lakes, rivers, reservoirs, ponds and other waters, often lurking in the bottom layer of the water and using its pectoral fins to maintain body balance. The snakehead has strong adaptability to changes in environmental factors in the water, especially to hypoxia, water temperature changes and poor water quality. When the water is short of oxygen, it can raise its head above the surface and directly breathe oxygen from the air through the suprabranchial organ in the gill cavity. Even with little water or even out of water, as long as the gills and body surface maintain a certain moisture, it can still survive for a relatively long time. The survival water temperature of the snakehead is 0°C-41°C, and the optimum water temperature is 26°C-28°C. When the water temperature reaches above 8°C in spring, it often moves in the middle and upper layers of the water; in summer it often moves in the upper layer of the water; when the water temperature drops below 6°C in autumn, it swims slowly and often lurks deep at the bottom of the water; when the water temperature is too low in winter, it buries the rear half of its body in mud or grass piles, with its head exposed in the water, neither eating nor moving. The snakehead has a very strong jumping ability. When the weather is hot and humid and the water rises after rain, the snakehead often leaps out of the water and escapes along the banks; when struck by flowing water, it also often leaps and escapes, and when escaping its body moves slowly forward in a snake-like manner.

(III) Feeding habits and growth

The snakehead is a typical ferocious carnivorous fish. In nature, the snakehead mainly feeds on small fish, shrimp, frogs, tadpoles, aquatic insects and other aquatic animals. Because of differences in fish body size and habitat environment, the types of food it consumes also differ. During the fry stage, it mainly feeds on copepods, cladocerans and chironomid larvae; when the body length reaches more than 3 cm, it shifts to mainly feeding on aquatic insects and also eats some small fish and shrimp; when the body length reaches more than 8 cm, fish and shrimp become the main feeding targets. It is worth noting that as the fish grows, when food is insufficient or the size difference is too great, the snakehead has the habit of cannibalism. Therefore, when farming snakeheads, attention should be paid to stocking at a consistent size, especially during the seedling cultivation stage, and multi-level separate rearing should be carried out according to size. Under natural conditions, before the age of 2 years is the stage of accelerated body length growth for the snakehead, with vigorous growth; after the age of 2 years it enters the stage of sexual maturity, and the growth rate of the fish body slows down. Under artificial rearing conditions, when extruded feed is used for feeding, after 4 months of farming in the high-temperature summer season, Channa maculata (Hong Kong breed) can reach 10-12 jin, and the hybrid can reach 2 jin after 3 months of farming.