Channa barca (HAMILTON, 1822)

SynonymsTop ↑

Ophiocephalus barca Hamilton, 1822; Ophicephalus nigricans Cuvier, 1831

Etymology

Channa: from the Latin channe, used to refer to an unspecified species of sea perch.

barca:

Classification

Order: Perciformes Family: Channidae

Distribution

Appears restricted to the states of Assam and Nagaland in northeastern India but is scarce and never collected in numbers.

In Assam it’s been recorded in Kamrup and Morigaon districts during recent years, while its occurrences in Nepal and Bangladesh is said to be doubtful.

Type locality is ‘Brahmaputra River near Goyalpara, Assam, India’, with ‘Goyalpara’ referring to modern-day Goalpara district in Assam.

Habitat

Has been observed to inhabit vertical burrows around the margins of wetlands which typically become dry during winter months.

These burrows are most often around a metre deep and consist of one or more entrance tunnels leading to a larger chamber within the ground water table.

The fish use them as refuges during the dry winter months, emerging to hunt and breed while the habitat is flooded.

Since it is less of an ecological generalist than many Channa species, requires a specific type of microhabitat, has a restricted range and is never found in large numbers it is recommended as a concern for conservation (Gosawami et al., 2006).

Maximum Standard Length

800 – 900 mm.

Aquarium SizeTop ↑

Suitable only for public installations or the very largest private aquaria.

Maintenance

Relatively unfussy although some  surface cover in the form of floating or overhanging vegetation or branches is appreciated.

It’s essential to use a tightly-fitting hood since Channa spp. are notorious for their ability to escape, and a gap should be left between this and the water surface as they require access to a layer of humid air.

More importantly still C. barca must not be maintained at a constant temperature but provided with natural seasonal variation in the form of defined winter and summer periods.

During the colder period the fish do not require much food and the water level can be allowed to fall without additional top-ups.

Water Conditions

Temperature: 10 – 28 °C

pH: 6.0 – 8.0

Hardness: 36 – 357 ppm

Diet

An obligate predator which probably feeds on smaller fishes and insects in nature but in most cases adapts well to dead alternatives in captivity.

Some specimens even accept dried foods though these should never form the staple diet.

Young fish can be offered chironomid larvae (bloodworm), small earthworms, chopped prawn and suchlike while adults will accept strips of fish flesh, whole prawns/shrimp, mussels, live river shrimp, larger earthworms, etc.

This species should not be fed mammalian or avian meat such as beef heart or chicken since some of the lipids contained in these cannot be properly metabolised by the fish and may cause excess fat deposits and even organ degeneration.

Similarly there is no benefit in the use of ‘feeder’ fish such as livebearers or small goldfish which carry with them the risk of parasite or disease introduction and at any rate tend not have a high nutritional value unless properly conditioned beforehand.

Behaviour and CompatibilityTop ↑

Best-maintained in a species-specific aquarium.

It is aggressively territorial towards conspecifics and violence can occur suddenly and without warning even in pairs or groups which have been maintained together for extended periods of time.

Sexual Dimorphism

Males begin to develop a more-extended, intensely-patterned dorsal-fin once they reach a size of around 150 mm.

In most cases adult fish can also be sexed by viewing them from above since females have a broader head shape.

Reproduction

Unrecorded but likely to be a mouthbrooder.

NotesTop ↑

This species is rarely available and extremely expensive to buy but is considered highly desirable in the aquarium hobby.

It can be distinguished from other Channa species by the following combination of characters: 62-63 lateral line scales; 50-51 dorsal-fin rays; 33-34 anal-fin rays; 56 total vertebrae; two large cycloid scales on each side of lower jaw undersurface; dorsal-fin and flanks covered in numerous black spots; pectoral-fin reddish with black bars comprised of spots.

Members of the family Channidae are commonly referred to as ‘snakeheads’ due to possession of large scales on the head of most species which are reminiscent of the epidermal scales (cephalic plates) on the heads of snakes.

There currently exist over 30 valid species but diversity within the group is likely to prove significantly greater.

The existence of distinct phylogenetic groups has been proposed with the putative C. gachua species assemblage of Britz (2008) containing C. orientalis, C. gachua, C. bleheri, C. burmanica, C. barca, C. aurantimaculata, and C. stewartii.

Species from northeastern India have also been divided into the C. marulius and C. gachua groups (Vishwanath and Geetakumari, 2009).

C. barca was included in the latter assemblage which the authors characterise by possessing the following combination of characters: presence of a U-shaped isthmus; cephalic sensory pores evenly arranged in a single row; presence of one or two large cycloid scales on each side of the lower jaw; absence of a sharp prominent spine-like hypurapophysis; absence or presence of one tooth plate in the epibranchial; absence of an elongated urostyle.

All Channa spp. possess supplementary breathing apparatus in the form of paired suprabranchial chambers located behind and above the gills, although these are not labyrinthic but lined with respiratory epithelium.

These chambers allow the fish to breathe atmospheric air and survive in hypoxic conditions or even out of the water for a considerable period of time, and in aquaria they are often seen rising to the surface to take gulps of air.

References

1. Hamilton, F., 1822 - Edinburgh & London: i-vii + 1-405
   An account of the fishes found in the river Ganges and its branches.
2. Brede, N. and P. Antler, 2009 - Natur und Tier Verlag, Münster: 62 pp.
   Schlangenkopffische—Die Gattungen Channa und Parachanna.
3. Britz, R., 2008 - Ichthyological Exploration of Freshwaters 8(4) [for 2007]: 335-344
   Channa ornatipinnis and C. pulchra, two new species of dwarf snakeheads from Myanmar (Teleostei: Channidae).
4. Goswami, M. M., B. Arunav and P. Janardan, 2006 - Journal of the Inland Fisheries Society of India 38(1): 1-8
   Comparative biometry, habitat structure and distribution of endemic snakehead (Teleostei: Channidae) species of Assam, India.
5. Vishwanath, W. and Kh. Geetakumari, 2009 - Journal of Threatened Taxa 1(2): 97-105
   Diagnosis and interrelationships of fishes of the genus Channa Scopoli (Teleostei: Channidae) of northeastern India.