Actinopteri (ray-finned fishes) > Siluriformes
(Catfishes) > Claroteidae
(Claroteid catfishes) > Claroteinae
Etymology: Chrysichthys: Greek, chrysos = golden + Greek, ichthys = fish (Ref. 45335).
Environment: milieu / climate zone / depth range / distribution range
Freshwater; brackish; demersal; potamodromous (Ref. 51243). Tropical; 26°C - 31°C (Ref. 27935); 36°N - 2°N, 16°W - 34°E (Ref. 7324)
Africa: known from most of the West African hydrographic basins, except in the coastal areas between Gambia and Liberia, where it is replaced by Chrysichthys maurus (Ref. 7324, 57126). Present from southern Liberia to Cabinda (Angola) (Ref. 57126), and widespread throughout Lower Guinea (Ref. 81642). Also reported from the Chad (Ref. 3236, 57126) and Nile (Ref. 3236, 2988, 28663, 78586) basins.
Length at first maturity / Size / Weight / Age
Maturity: Lm 11.0, range 8 - 19 cm
Max length : 57.0 cm TL male/unsexed; (Ref. 41031); 35.0 cm SL (female); max. published weight: 0.00 g
Morphology | Morphometrics
spines: 0. Diagnosis: 1st branched dorsal-fin ray longest, nearly always extended into a long filament that may reach, or even exceed, the base of the caudal fin; in some individuals or populations (Mafou on the upper Niger; rivers Cross, Ogowe, Nyong; Sanaga estuary) this filament is strongly reduced, but the first branched ray remains the longest (Ref. 57126, 81642). In other populations this filament is particularly elongate (Sanaga mainstream and coastal rivers of Cabinda)(Ref. 81642). Usually 8 branched rays in pectoral fins (Ref. 57126, 81642), rarely 7 or 9 (Ref. 57126, 81642), 2nd and 3rd rays sometimes filamentous (Ref. 57126). Exhibits pronounced intraspecific variability, and a clinal series can be demonstrated in the size of the adipose fin and the number of gill rakers (Ref. 81642). Either 9-13 gill rakers on lower limb of first gill arch and base of adipose fin longer than dorsal-fin base (Nilo-Sudanese region = populations from Nile, Chad, Senegal and the upper courses of the Niger, Comoé, Benue and Volta), or 12-15 lower gill rakers and base of adipose fin shorter than, or equal to, dorsal-fin base (coastal zones from Liberia to Cabinda); populations from the middle and lower courses of coastal rivers in this region are more or less intermediate in regard to these characters (Ref. 57126, 81642). Pronounced dimorphism between mature males in reproductive activity and immature males (Ref. 57126, 81642).
In those parts where Chrysichthys maurus and Chrysichthys auratus overlap (from Liberia to Ghana, to the east of the Volta), C. auratus does not enter rivers, but remains in estuaries and lagoons, where both species are sympatric; in the coastal region, C. auratus has been reported as C. filamentosus (Ref. 57126). Found in lakes and coastal rivers (Ref. 3236) and appears to tolerate a certain amount of salt (Ref. 78218). Occurs usually over soft, slightly muddy substrates or substrates with heavy layers of leafy detritus in deep, relatively quiet waters (Ref. 6868). Feeds on mollusks and small crustaceans (Branchiopods, Copepods, Ostracoda) which it digs from the substrate (Ref. 27935), and also on insects (Ref. 28714) and fish (Ref. 28714, 78218).
Risch, L.M., 2003. Claroteidae. p. 60-96 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. 57126)
IUCN Red List Status (Ref. 125652)
Threat to humans
Estimates based on models
Phylogenetic diversity index (Ref. 82804
= 0.5000 [Uniqueness, from 0.5 = low to 2.0 = high].
Bayesian length-weight: a=0.01122 (0.00821 - 0.01533), b=2.97 (2.90 - 3.04), in cm total length, based on LWR estimates for this species (Ref. 93245
Trophic level (Ref. 69278
): 3.7 ±0.55 se; based on food items.
Generation time: 6.9 ( na - na) years. Estimated as median ln(3)/K based on 2 growth studies.
Resilience (Ref. 120179
): Medium, minimum population doubling time 1.4 - 4.4 years (K=0.16; Fec > 1,000).
Fishing Vulnerability (Ref. 59153
): Low to moderate vulnerability (27 of 100).