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ith the assistance of Roger Bills of the South African Institute of Aquatic Biodiversity we have treaded on new territory this month (April 2014) with a little known South African catfish family, namely the Austroglanididae,which comprises of only three species of medium to large sized fishes, Austroglanis barnardi (Skelton, 1981), Austroglanis gilli (Barnard, 1943) and Austroglanis sclateri (Boulenger, 1901). The subject of our factsheet this month is the Barnard's Rock Catfish, Austroglanis barnardi.

Austroglanis barnardi

Austroglanis barnardi is the smallest of the three species and prefers fast flowing, rocky habitats of headwater streams. They seem to be restricted to cobble zones of the lower gradient sections of tributary streams (Bills 1999). This species is critically endangered and uncommon due to their habitats being threatened by stream channeling, water extraction, sedimentation and introduced small mouth bass (Micropterus dolomieu Lacepède, 1802) and competition for food as a result of the presence of species such as bluegill (Lepomis macrochirus Rafinesque, 1819). It will probably never be imported to our aquariums due to the above limitations. A. barnardi only occurs in three tributary streams of the Olifants system – all three are on the western side of the Cederberg mountains (see map below). They have been recorded in recent times in the mainstream of the Olifants River, but unsustainable water extraction has caused these areas to dry up several times in the last few years, suggesting that this area is recolonised from the Heks population.

The placement of barbels on the lower jaw is characteristic of this family, they are positioned far back and off the jaws bones which is unusual, most catfishes are on the jaw. Similar to the Bagridae/Claroteidae where they were once formerly placed in the Bagridae family, but recognized in a separate family by Mo (1991) and de Pinna (1998). Austroglanis catfishes live much longer than we expected, the maximum age of 12+years for A. gilli and 14+years for A. barnardi (Mthombeni, V. G.; 2009).

Type Locality for Austroglanis barnardi. Olifants system, Western Cape. Typical habitat is shallow cobble riffles and runs. They don’t seem to like deeper pools.

Barnard's Rock Catfish, Spotted Rock Catfish

Gephyroglanis barnardi

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South Africa: Streams in Clanwilliam-Olifants River system. Type locality: Noordhoeks River at roadbridge, tributary of Olifants River, Cape Province, S. Africa, 32º43'15"S, 19º03'59"E.

8.0cm (3¼ins)

23-26°C (73-79°F)

D1, 6; A iii-vi, 10-13. Fins short, rounded; dorsal with weak spine, pectorals with short curved spine, adipose fin large, caudal truncate. Humeral process stubby. Head depressed, snout broad; three pairs of short barbels (nasals insignificant) mandibulars on ventral side of head.

Very aggressive with each other and seemed to maintain territories so would need plenty of caves etc. laid out so they would be out of site of conspecifics. "I have kept all three species in aquaria – all quite difficult to maintain in good condition. Best results were with A. barnardi – I had them in a recirculating circular tank. Packed peat into the filter and pushed the pH right down. Fed them on worms mostly although I assume they generally eat chironomids, mayflies and caddis mostly in the wild. They were very aggressive with each other and seemed to maintain territories" (Roger Bills).

"I did spawn them in the field – I collected gravid fish and injected them with hormone and did get them to spawn but did not get viable eggs. The eggs were however adhesive and spawned in a single clump suggesting nesting. Their aggressive behaviour would suggest to me that they are also guarders of eggs" (R. Bills).

No discernable differences.

In their natural habitats, Austroglanis species feed on benthic invertebrates, including insects of the orders of Ephemeroptera (mainly Baetidae) and Diptera (mainly Chironomidae). Fed them on worms mostly although I assume they generally eat chironomids, mayflies and caddis mostly in the wild. (Mthombeni, V. G.; 2009).

Dorsal fin: The primary rayed fin(s) on top of the body.
Caudal fin: The tail.
Anal fin: The median, unpaired, ventrally located fin that lies behind the anus, usually on the posterior half of the fish.
Adipose fin: Fleshy finlike projection without rays, behind the rayed dorsal fin.
Pectorals: The paired fins just behind the head.
Mandibular barbels: Pertaining to the lower jaw. (mandibular barbels).
Nasal barbels: On top of the head, by the nostrils. (nasal barbels).

Austroglanis: Austro = the south + Greek, glanis = a fish that can eat the bait without touching the hook; a cat fish.

Bills R. (pers comm).
Mthombeni, V. G.; 2009 The biology of Austroglanis gilli and Austroglanis barnardi (Siluriformes: Austroglanididae) in the Olifants system, Western Cape, South Africa.
Skelton, P.H. 1993 A complete guide to the freshwater fishes of southern Africa. Southern Book Publishers. 388 p.
Scott L. E. P.; Skelton, P.H.; Booth, A.J.; Verheust L.; Harris, R.; Dooley, J.; Atlas of Southern African Freshwater Fishes. South African Institute for Aquatic Biodiversity, 2006 - Fishes - 303 pages.
Swartz, E., Bills, R. & Impson, D. 2007. Austroglanis barnardi. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2.

Photo Credits

© Roger Bills @
Map: Atlas of Southern African Freshwater Fishes.