Marcusenius conicephalus Taverne, Thys van den Audenaerde and Heymer, 1976
Species overview
Medium-sized fish, body elongate. moderately deep, head uneven blunt-snouted, base of dorsal fin two times as long as base of anal, caudal fin with round scaled lobes and obtusely pointed membranes. Size observed: 189 mm SL.
M. conicephalus(measurements)
Taxonomic description
-Body elongate, moderately compressed, moderately deep, body depth 21-25 % SL, greatest depth above pelvic fin.
-Head conical, head length 24-28 % SL, head depth 17-20 % SL, 73-87 % body depth.
-Outline of back convex, sloping into the convex upper profile of head of the snout; underside of head concave; outline of belly slightly convex.
-Snout obtusely pointed, 21-29 % head length, 33-46 % postorbital length.
-Mouth small, 9-14 % head length, terminal, its edge before anterior nostril and well below level of pectoral fin, upper jaw on a level with lower edge of base of pectoral fin.
-Chin with strong but short globular swelling which is pointing downward.
-Teeth notched, 6/8.
-Nostrils separate, circular. posterior on a level with lower rim of eye, anterior above it, axis of nostrils making an angle of about 45° to axis of head; distance between nostrils 18-15 % length of snout, distance posterior nostril to eye 21-30 % length of snout.
-Eye small, its diameter 8-12 % head length, 12-17 % postorbital length.
-Opercular cleft slightly curved, 32-46 % head length, 39-60 % head depth.
-Dorsal fin 20-21 fin-rays, base of D 14-17 % SL, anal fin 29-32 rays, base of A 21-25 % SL, D originating behind origin of A, ending before end of A; predorsal length 65-70 % SL, preanal length 57-62 % SL.
-Pectoral fin obtusely pointed, extending beyond base of pelvic fin. V is closer to P than to A.
-Caudal fin rounded scaled and membranous lobes, the scaled lobes 1/3 as long as total fin. 64-66 scales in lateral line; 12 round caudal peduncle.
-Caudal peduncle 15-18 % SL, its depth 5-6 % SL, 29-41 % its length.
-Coloration Dark brown, even darker on the back, fin rays dark brown, membranes lighter.
Type locality
»Village Aboulou, rivère Korn, affluent de la rivière Ntem, Cameroun«. (02° 17 ‘ N 12° 52 ‘ E)
Distribution
South Cameroon: Nyong river, Ntem river (next location on Ntem: Minvoul 2°08'N 12°12'E), Yété , North Gabon, district Ogôué-Ivindo, Makokou.
Electric organ discharges
M. conicephalus(elec. organ)