Silversides

There are 141 species of fish recorded in the Senegal River, most of which are native; however, there are no endemic species of fish in the Senegal Basin. Among the larger native benthopelagic taxa are: the 170 centimetre (cm) North African Catfish (Clarias gariepinus), the 149 cm Electric Catfish (Malapterurus electricus), and the 92 cm African Carp (Labeo coubie).

Some of the larger native demersal fishes of the Senegal Basin are: the 204 cm Aba (Gymnarchus niloticus). the 200 cm Nile Perch (Lates niloticus), the 183 cm Sampa (Heterobranchus longifilis), and the 150 cm Cornish Jack (Mormyrops anguilloides).

Pelagic native fishes in the Senegal River include the 65 cm True Big-scale Tetra (Brycinus macrolepidotus) and the 16 cm Ansorge Fangtooth Pellonuline (Odaxothrissa ansorgii)

Diagnosis: fronto-parietal fontanel absent in adults, sometimes pore-like in juveniles; snout long, comprimised 3x in head length; dorsal fin origin distinctly behind pelvic fin insertion; adults large-sized; no sexual dimorphism affecting anal fin shape; 21-31 lateral line scales; 4.5 scales between lateral line and dorsal fin; 10-16 anal fin branched rays; 14-22 gill rakers on lower limb of first gill arch; 8-14 teeth in outer premaxillary row (Ref. 2880, 80290, 81279). Head length/snout length 2.6-2.9; 10-12 predorsal scales (Ref. 80290). Body depth more than 3x SL in adults (Ref. 2880, 81279). Description: anal fin with 3 branched and 10-16 unbranched rays; 8-14 premaxillary teeth, two of which shift progressively backwards with growth; supraorbital bone well-developed; upper jaw projecting beyond lower jaw in adults (Ref. 2880, 80290, 81279). Coloration: humeral spot; black precaudal blotch extending partly unto median caudal-fin rays; greenish back, white belly; juveniles with white spot on upper part of caudal peduncle (Ref. 2880, 80290, 81279). Sides sometimes with an orange (Ref. 2880, 81279) or broad dark (Ref. 80290) longitudinal band from opercle to caudal fin in adults only. This color pattern is not correlated with sexual activity (Ref. 2880, 80290, 81279). In most fish fin color varies from red-orange or pink (Ref. 2880, 80290, 81279) to grey (Ref. 80290). In some populations fin margins are trimmed with dark pigment (Ref. 80920). Only live specimens from Cavally River (Côte d'Ivoire) have vermillion red fins (Ref. 2880, 81279).

Annulotrema Infestation 4. Parasitic infestations (protozoa, worms, etc.)

Potamodromous. Migrating within streams, migratory in rivers, e.g. Saliminus, Moxostoma, Labeo. Migrations should be cyclical and predictable and cover more than 100 km.

Anal spines: 0; Analsoft rays: 13 - 19

More common in rivers than lakes; feeds on insects, crustaceans, fish, vegetation and debris (Ref. 28714). Considering the distribution of different forms (according to collection determinations), it should be noted that a B. macrolepidotus 'form' is found only in northern regions, while a B. schoutedi 'form' is found only in southern regions. However, between these two forms there appears to be mixing and intermediacy of forms. We consider that there are several populations which have evolved in a geographical gradient to produce different morphotypes of a single species (Ref. 80290).

fisheries: commercial

AMNH 240383, 6, 1 C&S;