Cave catfish  (Clarias cavernicola)

Cave catfish

Facts

Kingdom Animalia
Phylum Chordata
Class Actinopterygii
Order Siluriformes
Family Clariidae
Genus Clarias (1)
Size Length: 16.1 cm (2)

Status

Classified as Critically Endangered (CR) on the IUCN Red List 2007 (1).

Description

The cave catfish is a freshwater, cave-dwelling fish (2). This unusual fish lacks pigment and appears a pinkish white colour (5). It has an extended eel-like body, with long dorsal and anal fins (3). The head has a rectangular shape and the rounded snout (2) carries four pairs of thread-like barbels (4). On the upper surface of the head the eyes are either entirely absent or extremely small and covered with skin (2). The Latin species name, cavernicola, means 'cave dwelling'.

Range

Found only in the Aigamas Cave in Namibia (2).

Habitat

Inhabits open, clear water over rocky shelves (6).

Biology

This cave-dwelling fish feeds opportunistically on particles that fall into the lake, from bat droppings to animal carcasses and insects (2). Due to the lack of light in the cave where it lives, this species is sightless, detecting prey by means of taste buds and other senses on the barbels (3). There is currently no data available on its breeding habits (5).

Threats

The cave catfish is found only within a single cave in Namibia and is therefore at inherent risk of extinction due to any chance event. The main threat to the species comes from the depletion of ground water within the cave, and the exploitation of aquifer water may pose the most serious threat in the long-term (5).

Conservation

The protection of the Aigamas Cave is vital in the conservation of this species, and the present owner is sympathetic to the sensitivity of the cave, only allowing access or collection of the cave catfish with a Nature Conservation Permit (5). Twenty captive specimens were held in the National Zoological Gardens' aquarium in Pretoria for several years (5), but no longer persist (7). There is also a move to provide legislative protection for this rare and unique fish (5).

Authentication

Authenticated (6/9/02) by Professor Paul Skelton. Managing Director, South African Institute of Aquatic Biodiversity (SAIAB)
http://www.saiab.ru.ac.za/

Anal fin: In fish, an unpaired fin on the under surface of a fish, behind the anus.
Barbels: Fleshy projections near the mouth of some fish.
Dorsal fin: In fish, the unpaired fin found on the back of the body.

References

  1. IUCN Red List (March, 2008)
    http://www.iucnredlist.org
  2. Fishbase (August, 2002)
    http://www.fishbase.org/Summary/SpeciesSummary.cfm?ID=2106&genusname=Clarias&speciesname=cavernicola
  3. Sands, D. (1985) Catfishes of the World, Volume 5: Bagridae and others. Dee Bee Books, Preston.
  4. Paxton, J.R. and Eschmeyer, W.N. (1994) Encylopedia of Fishes. UNSW Press, Sydney.
  5. Skelton, P.H. (1987) South African Red Data Book - Fishes. South African National Scientific Programmes report, 137: 33 - 35.
  6. Skelton, P.H. (2001) A complete Guide to the freshwater fishes of southern Africa. Revised Edition. Struik Publishers, Cape Town.
  7. Skelton, P.H. (2002) Pers. Comm.