Channa asiatica


{pronunciation} azy-attick-a

Common name:

Northern-Green Snakehead; 'hua-t'sai-yu = local Chinese name

First description:

Linnaeus, C. 1758
Gymnotus asiaticus
Systema Naturae: Vol.1; p.246.

Meristic:

D: 43-46 A: 28-30 C: rounded V: absent Ratio: 3.3- 4.0

Lateral line scale count:

52-58

Description:

The unpaired fins are coloured brownish-olive to grey. The dorsal exhibits numerous scattered white/silvery/gold spots, whilst the anals have similar white and silvery speckles. The pectorals are clear.

The overall ground body colour is a brownish-olive. There are 8-11 V-shaped bands and an occelated dark brown blotch ringed with gold at the base of the caudal. The ventral region is white with another blotch at the base of the pectoral fin. Sparkling pearly speckles cover the body. Gold spots adorn the head and flanks. There are two broad stripes running from the eye to the edge of the opercle orbit.

Juvenile differences in colouration:

At a size of 150 mm, the overall body colour is orange/brown lightening to a creamy white below. Young exhibit a more distinct, but similar pattern to the adults.

Size:

A medium-sized snakehead, reaching a length of 255 mm

Sub-species and colour variants:

Colour Form:
In some recently imported aquarium specimens, the anal fin appears to lack its familiar pigmentation.

Synonyms:

Gymnotus asiaticus, Sternarchus asiaticus, Channa asiatic, Channa asiaticus, Channa fasciata, Channa formosana, Channa ocellata, Channa sinensis.

Geographical location:

This species, easily distinguished by its colour pattern and lack of ventral fins, can be found in ponds, lakes and rivers of south-eastern China. It is also known from Hainan Island but not found in the north of the Yangtze or the province of Szechuan (Shih 1936).

Maintenance:

Due to their reasonable size, a compatible pair can be kept together in a 120 x 30 x 30 cm fish tank. Average (24-26 C) aquarium temperature and water conditions are sufficient. In nature, this fish eats small fishes, shrimps and a small amount of vegetable matter and a similar diet will keep this fish in a healthy condition. It is very shy by nature.

Breeding:

A large-ish (120 x 45 x 30 cm), well-planted tank is recommended, with aged water at a temperature of about 21 C. When spawning time approaches, the female changes colour; her lighter parts turning pinkish whilst all her markings become more conspicious. The male becomes darker, distending his gill covers and spreading his fins. The male then displays silver 'dots' on the anal fin. The two fish meet and entwine their bodies into a ball which, as spawning is taking place, rises to the surface, turns over then sinks to the bottom where they, and the fertilized eggs are released. This activity continues for up to 12 hours.

No bubblenest is built and the large floating eggs hatch within 36-72 hours (at a temperature of 26.5 C ). A certain amount of parental care is observed ( Breder & Rosen 1966), with the male fetching stragglers who have wandered away from the main school and attacking any foreign objects introduced into the tank. The yolk sac will be absorbed in 4 days and the fry will be free swimming (6-7mm) within a week.

Even with 90% water changes every other day and a large amount of food (Cyclops and Artemia) this was not enough to raise the 300 fry. Large numbers of fry were removed from the tank with fins damaged and missing from fighting and cannibalism, although the parent fish seemed not to eat their young.