Actinopteri (ray-finned fishes) > Siluriformes
(Catfishes) > Clariidae
Etymology: Gymnallabes: Greek, gymnos = hidden + Greek, allabes, -etos = a fish of the Nile, a kind of lamprey (Ref. 45335). More on author: Günther.
Environment: milieu / climate zone / depth range / distribution range
Freshwater; demersal; depth range - m (Ref. ), usually - m (Ref. ). Tropical; 0°C - ; 17°N - 2°N
Africa: lower reaches and the delta of the Niger (Nigeria) and the Cross basin (Nigeria and Cameroon)(Ref. 57129, 81644). Also reported from the rivers Ouémé (Benin) (Ref. 57129, 81644) and Osse (Nigeria)(Ref. 57129).
Size / Weight / Age
Maturity: Lm ?  range ? - ? cm
Max length : 29.7 cm TL male/unsexed; (Ref. 81644)
Morphology | Morphometrics
soft rays: 83 - 94. Diagnosis: dorsal and anal fins always confluent with caudal fin (Ref. 57129, 81644). Body very elongate, maximum body depth 14-15% standard length (Ref. 57129), abdominal depth 4.5-8% SL (mean 6) (Ref. 81644). Head very short, 12.5-14.3% standard length; lateral cephalic bones separated from each other by a distinct gap (Ref. 57129). Distance between supraoccipital process and dorsal fin short, 5-14% SL; pectoral fins present, 30-56% skull length, supported by a short spine (about half of fin length); pelvic fins always present and short; skull short, 11-18% SL (mean 13), with a very narrow roof, 9-23% (mean 14) head length, partially covered by jaw muscles; these muscles almost completely exposed dorsally and laterally and frequently bulging (especially in larger specimens); supraoccipital process short and narrow, 10-20% (mean 16) head length; eyes very small (4-9%), bordered by small infraorbital bones (hard to observe externally); barbels long, maxillary longest (86-155% skull
length); maxillary barbel connected at base to large skin folds that border mouth opening; when mouth is closed, these skin flaps are folded and conspicuous in dorsal view; internal mandibular barbel shortest, 58-99% (mean 76) head length (Ref. 81644).
Coloration: in life: uniformly light brown (Ref. 81644). Preserved specimens: brownish-black on back and sides, light brown on belly (Ref. 57129). Ventral prepelvic region slightly paler than rest of body (Ref. 81644).
Prefers small streams and ditches with leaf litter. Also found in swamp regions. Diet probably consists of insect larvae, worms and similar smaller organisms. Fishes are not eaten (Ref. 78218).
Life cycle and mating behavior
Maturity | Reproduction | Spawning | Eggs | Fecundity | Larvae
Teugels, G.G., 2003. Clariidae. p. 144-173 In C. Lévêque, D. Paugy and G.G. Teugels (eds.) Faune des poissons d'eaux douce et saumâtres de l'Afrique de l'Ouest, Tome 2. Coll. Faune et Flore tropicales 40. Musée Royal de l'Afrique Centrale, Tervuren, Belgique, Museum National d'Histoire Naturalle, Paris, France and Institut de Recherche pour le Développement, Paris, France. 815 p. (Ref. 57129)
IUCN Red List Status (Ref. 124695)
Threat to humans
Common namesSynonymsMetabolismPredatorsEcotoxicologyReproductionMaturitySpawningSpawning aggregationFecundityEggsEgg development
ReferencesAquacultureAquaculture profileStrainsGeneticsAllele frequenciesHeritabilityDiseasesProcessingNutrientsMass conversion
Estimates based on models
Phylogenetic diversity index (Ref. 82805
= 0.7500 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.00102 (0.00046 - 0.00225), b=3.06 (2.88 - 3.24), in cm total length, based on all LWR estimates for this body shape (Ref. 93245
Trophic level (Ref. 69278
): 3.4 ±0.5 se; based on size and trophs of closest relatives
Resilience (Ref. 120179
): High, minimum population doubling time less than 15 months (Preliminary K or Fecundity.).
Vulnerability (Ref. 59153
): Low to moderate vulnerability (25 of 100) .