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he first factsheet of the new dacade of 2010 is by all accounts an unusual one as it centres on a catfish that looks more like an eel with barbels, hence its common name of the "Eel Catfish".

Channallabes apus

Channallabes apus was first described in 1873 by the eminent zoologist Albert Günther and was named as Gymnallabes apus. It was then moved into a family of its own, Channallabes(due to the cranial morphology), and was the only species in this genera (monotypic) for many years until DEVAERE et al. 2007 named another five species which added up to six in all in this family. They are all very like each other and some are difficult to name, when live, to an exact species.

This is a nocturnal species and ideally should be housed in a dimly lit tank no less than 4ft long with hiding places and a soft substrate such as sand or small rounded gravel, as it likes to burrow into the substrate, so there should be no sharp edges there to scar its soft body parts. Provide a close fitting lid to your tank as they could, due to thier shape, make an escape this way. The image below shows the perfect setup for the "Eel Catfish". They do like to socialise with their own, so three or four specimens would get on well together.

Channallabes apus - the perfect setup.

Channallabes apus - an unusual catch, a red colour form captured by fish importer Thomas Kobe from a cave system in the Congo

In their natural environment they inhabit forest streams and swamps where they burrow into the substrate or make nests in the masses of tree roots that are exposed near the banks. It tends to avoid light so it is increasingly difficult to capture by conventional collecting techniques. They are caught in a traditional manner, by means of fykes, made of bamboo strips, or fish hooks and bait. These hooks are made of a recurved spine of the African porcupine (Aethiurus africanus), and are attached to a wire made from fibers, obtained from the bark of a specific tree. The fykes, on the other hand, are submerged into the mud or surface water, into a hand made burrow, into which some parts of a nest of tree termites are put out to attract the fish. These fykes are then left over night, and collected in the early morning (University of Ghent; Gabon expedition 1999).

In the Clariidae family (air-breathing catfish) which includes the various Clarius species, a complete range of fusiform to anguilliform body shapes can be observed. The cranial morphology of Channallabes apus, an extreme anguilliform (eel like) species, compares to the anguilliform Gymnallabes typus and the more fusiform Clarias gariepinus.

The Eel- catfish may look primitive compared to the Clarius spp. but they are more highly evolved or specialised and have undergone evolutionary changes due to environmental pressures, and have lost many of the structures that the various Clarius spp. possess in order to adapt to a special ecological niche. They also posses a powerful bite when attacking prey and can shoot out from their hiding place in a head down position to grab food. As with other members of the Clariidae, they can venture on land and can also take food this way.

Eel Catfish

Gymnallabes apus

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Africa: Angola to Congo River Basin. Type locality: Interior of Ambriz, Angola.

30.5cm. (12¼ins)

22-25°C (71-77°F)

The dorsal continues round the body and unites in a single fin incorparating the caudal and anal fins. Dorsal 140-150 rays. Anal fin 125-130 rays. The head has two fontanelles, a frontal fontanelle that is sole-shaped and a occipital fontanelle which is smaller and has a tear drop shape. Four pairs of barbels. Very small eyes (microphthalmic).

Better to have this species as the only catfish in the tank. Tank mates could include larger African barbs or characins, such as Congo Tetras that don't encroach in their territories, and keep themselves to the upper layers of the water.

There has only been sporadic accounts in the aquarium, but in their natural habitat they make nests in the masses of tree roots that are exposed near the banks.

Females grow larger than the males.

Omnivore: In the wild they feed on Coleoptera (beetles) worms and shrimps. In the aquarium, tablet food and any larger live foods such as earth worms, and frozen foods such as bloodworm and shrimp.

Fontanelle: The space(s) between the bones on top of the skull covered by skin.
Dorsal fin: The primary rayed fin(s) on top of the body.
Maxillary: Pertaining to the upper jaw. (maxillary barbels).
Anal fin: The fin forward from the anal cavity.

Channallabes: Channe = a sea perch; al-to; labes = stain.
apus: From the Greek; a- meaning without, and pous, meaning foot; in reference to the lack of any pelvic fins.

Taylor E.C. Incidental Imports. The Eel Catfishes. Tropical Fish Hobbyist Dec. 1982.
Baensch, H.A. and R. Riehl 1985 Aquarien atlas. Band 2. Mergus, Verlag für Natur- und Heimtierkunde GmbH, Melle, Germany. 1216 p.
Devaere S, Adriaens D, Verraes W, and Teugels G.G. 2001. Cranial morphology of the anguilliform clariid Channallabes apus (Günther, 1873) (Teleostei: Siluriformes): are adaptations related to powerful biting? J. Zool., Lond. 255, 235±250.
University of Ghent; Gabon expedition 1999.

Photo Credits

© amiidae @
Bottom image: © Thomas Kobe