Channallabes apus
(Günther, 1873) |
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 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.
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Channallabes apus: the
perfect setup.
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The above image shows an unusual
catch, a red colour form captured by fish importer Thomas
Kobe from a cave system in the Congo.
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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.
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)
Body dark brown, underside in front of
the anal fin may be lighter. The colour of the substrate in the
aquarium appears to make a difference in the light ness or darkness
of the body.
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
| Sexual
differences |
Females grow larger
than the males.
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| Feeding |
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.
| Etymology |
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.
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| Glossary
of Terms |
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.
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| References |
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. http://www.fun-morph.ugent.be/Miscel/Expeditions/Expeditions.htm
© amiidae
@ 
Bottom image: Thomas Kobe |
