Marcusenius fuscus (Pellegrin, 1901)
Species overview
Medium-sized fish, body elongate, moderately compressed, not particularly deep, head uneven blunt-snouted, pectoral and caudal fin rounded, coloration uniform brown.
Size observed: 202 mm SL, 219 mm TL.
M. fuscus(measurements)
Taxonomic description
-Body elongate, moderately deep, body depth 22-23 % SL, greatest depth more or less above pelvic fin.
-Head about as long as body depth, 21-23 % SL, head depth 16-19 % SL, 70-83 % body depth.
-Outline of back rather straight between dorsal fin and neck; upper profile of head convex, underside of head concave, outline of belly slightly convex.
-Snout 23-26 % head length, 38-44 % postorbital length.
-Mouth width 17-21 % head length, terminal, its edge below anterior nostril, upper jaw on a level with lower rim of eye.
-Chin with rather small globular swelling.
-Teeth feebly notched, 5-6/6.
-Nostrils separate, circular, anterior nostril on a level with upper rim of lens, posterior nostril on a level with lower rim. Distance between nostrils 1/2 or 2/3 their distance from eye; axis of nostrils cuts axis of head at an angle of about 45°.
-Eye moderate, its diameter 12-15 % head length, 20-25 % postorbital length, 33-60% snout length.
-Opercular cleft curved, 39-44 % head length, 50-55 % head depth.
-Dorsal fin 22-26 fin-rays, base of D 19-21 % SL, anal fin 31-34rays, base of A 23-25 % SL, origin of D behind origin of A, its end before end of A; predorsal length 60-64 % SL, preanal length 56-62 % SL.
-Pectoral fin rounded, extending beyond base of pelvic fin. V is closer to P than to A.
-Caudal fin rounded, scaled lobes covering more than half of it. 54-61 scales in lateral line; 8 round caudal peduncle.
-Caudal peduncle 16-17 % SL, its depth 6-7 % SL, 39-42 % its length.
-Coloration »Uniform chocolate brown«. Sometimes a dark band between origins of D and A.
Type locality
»Congo français«, without further indication. (Congo français to day: Gabon, Central African Republic, Congo brazzaville).
Paralectotype: »Ikengo, Democratic Republic of Congo, 0° 08’ S 18° 26’ E«
Distribution
Congo river; Congo basin, »Kunungu, village N’ Dva: 2° 06’ S 16° 26’ E; region of Mushie, river Kasaï: .3° 26’ S 16° 55’ E; river Tshuapa: 0° 14’ S 20° 50’ E; Kinshasa 4° 18’ S 15° 18’ E«.