Diagnosis |
Diagnosis: snout rectangular, neither rounded nor pointed, its length equal to mouth width; mouth very broad; premaxillary tooth plate broad (width 30-37% of head length); occipital process well developed, its width 57-87% (average = 70%) of its length (Ref. 57126).
Description: nasal barbels present; very short first dorsal spine; well developed second spine, weakly denticulate along posterior margin; pelvic fin with 1 unbranched and 5 branched soft rays; anal fin with 4-5 unbranched and 8-10 branched soft rays (Ref. 57126). Some of the meristic proportions may vary with populations: i.e., the dorsal, anal and caudal fins are longer in populations from the Moa, Mano, St. Paul, Cess (Nipoué) and Tano (Risch & Thys van den Audenaerde, 1985); these populations, and especially those from the River Tano, also seem to have longer nasal barbels; furthermore, gill-raker numbers are variable from one population to another, and in cases of low counts, the most anterior rakers are missing (Ref. 57126).
Coloration: live specimens from Liberia and Sierra Leone are yellowish, while those from Gambia are greyish or silvery; after preservation, all of them become greyish on head and back, and whitish on belly (Ref. 57126). |