Parachanna obscura


{pronunciation} ob-scure-a

Common name:

Dark brown Snakehead

First description:

Gunther, A. (1861)
Ophiocephalus obscurus
Catologue of the Acanthoperygian Fishes in Collection of the British Museum, London. Vol.3; pp. 476.

Description:

Meristic:

D: 40-45 A: 26-32 C: rounded V: present Ratio: 29.7- 35.5 %

Ll:

62-78

Description:

The upper body is of an olive/ochre pigmentation, displaying 8 irregular blackish spots. In the fawn/greyish middle region there are up to 10 irregular greyish brown/black blotches that run posterior of pectorals to the caudal peduncle. The pale yellow belly has irregular brown and blackish spots.

The head has a black patch and a broad dusky band that runs from the eye to the edge of opercle. Two black lines develop in a downward arc to the lower edge of gill cover. The crown of the head is almost black and underneath the chin, a white marbled effect be seen.

All the greyish olive fins are freckled black and white. However, all the above markings can considerably alter with age and the mood of the fish. The nostrils are short.

Juvenile differences in colouration:

George Boulenger (1916) states, 'Young have a broad lateral band to the root of the caudal fin, followed on the basal part of the latter, by a small, black, light- edged ocellar spot.' As the fish grows larger, the overall colour is a mottled grey, with darker areas.

Size:

410 mm in total length.

Synonyms:

Channa obscura, Ophiocephalus obscurus, Parophiocephalus obscurus.

Geographical location:

This stocky snakehead is distributed over a wide area across Africa, from Senegal to the White Nile and southwards to the Congo River. Precise locations are given by Boulenger (1916)and Bonou & Teugels (1985).

Maintenance:

C.obscura is the most commonly kept African snakehead in the aquarium. The water temperature of a 100 cm aquarium, should be between 26 and 28 C and, with a simple filter, will sustain one fish.

Breeding:

Vitamins were used by Armbrust (1963), to induce breeding. Spawning occurred 1-2 hours after sunrise. The male's appearance changed from a brown body colouration into a brilliant blue. The, usually dark brown, spots on the flanks, became a deep, dark, steel blue. Whilst the light spots on the female's fins turned blue, the brown spots on her body changed to a deeper shade of dark brown and this sharply contrasted with the beige-coloured background. The tips of both fishes' pectorals were a silvery white.

The partners circled one another in an open area of the layer of floating plants. The circling became more intense and then the male swam across the back of the female and wrapped his body around hers. At this moment, the genital organs were lying side by side. The embracing pair turned, then rolled in the water entwined together. The spawning lasted 10-20 seconds, then both fish relaxed and after a short rest the reproductive act recommenced. The female showed some slight damage to her fins, proving that the spawning had not been entirely peaceful.

More than 500 eggs were scattered at the water surface, although an area of a diameter of 30 cm, where the apparent spawning took place, was devoid of eggs. It can be assumed that in nature the plant covering at the spawning site will hide the eggs. Both fish guard the yellow-coloured eggs, each one a little smaller than a mustard grain. After 24 hours the eggs hatch. These eggs are very sensitive to light and fungus very quickly.

Because of the big yolk sacs, the little tails of the fry are hardly noticed. The fry hang by their bellies for 3 days at the water surface and after this time become free swimming . One week later they can be observed feeding for the first time on microworms, brine shrimp and Cyclops nauplii. When the fry are about 5 weeks old they are eating day old guppies and after 8 weeks they take small earthworms. The female should not be trusted, as at this later stage she will eat her young.