Marcusenius sanagaensis Boden, Teugels and Hopkins, 1997
Species overview
Medium-sized fish, body moderately elongate and deep, snout blunt, rounded and short; dorsal fin slightly shorter than anal, originating slightly behind it; two dark bands between unpaired fins, the second band not always clearly visible. Size observed: 136 mm SL, 162 m TL.
M. sanagaensis(measurements)
Taxonomic description
-Body moderately elongate, laterally compressed, body depth 27.53 ± 1.37* % SL, greatest depth near anal fin.
-Head length 23.03 ± 1.03 % SL, head depth ca. 21 % SL, 89.98 ± 5.14 % head length.
-Outline of back straight, upper profile of head strongly convex, underside of head slightly concave, outline of belly straight.
-Snout length 28.06 ± 1.20 % head length.
-Mouth wide, terminal, its edge reaching to posterior nostril, upper jaw on a level with upper edge base of pectoral fin.
-Chin with short globular (sub-mental) swelling.
-Teeth notched, 3-6/5-6.
-Nostrils separate, circular, their distance almost equally distant from eye and from contour of snout; anterior nostril on a level with centre of eye, posterior nostril on a level below lower rim of lens, their axis cutting axis of head at an angle of about 45°.
-Eye diameter 18.07 ± 1.81 % head length.
-Opercular cleft curved.
-Dorsal fin 24-28 fin-rays, base of D 23.25 ± 1.26 % SL, anal fin 29-33 rays, base of A 27.48 ± 1.43% SL, origin of D behind or opposite to origin of A, end of D before end of A; predorsal length 63.88 ± 1.56 % SL, preanal length 59.82 ± 2.08 % SL.
-Pectoral fin pointed, 20.22 ± 0.78 % SL, extending beyond middle of pelvic fin. V is closer to P than to A.
-Caudal fin obtusely pointed, scaled lobes obtusely pointed, 1/2 as long as entire fin. 49-56 scales in lateral line; 8 round caudal peduncle.
-Caudal peduncle length 17.65 ± 1.14 % SL, its depth 6 % SL, 34.24 ± 2.96 % its length at end of anal fin. *) mean ± standard deviation, after original description, as most other data.
-Coloration In life »: Colour of the body grey, with head a little darker. Two dark vertical bands between the dorsal fin and the anal fin, the first situated between the anterior ends of the two fins, the second between the posterior ends. The latter is not always visible«. The anterior band covered by 4, rarely 3, lateral-line scale rows.
Type locality
»Bankim, river Mbam (Cameroon) 6° 05’ N 11°30’ E; Nachtigal, river Sanaga (Cameroon) 4° 21’ N 11° 38’ E«.
Distribution
»At present, this species is only known from the Sanaga River basin in Cameroon. It has been recorded from the main river in the neighbourhood of Nanga-Eboko, Nachtigal and from the Mbam and its tributaries Noun, Nchi, Ndjim and Kim. (Foumbot, river Noun 5° 29’ N 10° 31’ E; river Ndjim 4° 49’ N 11° 30’ E; Mantoum, river Nchi 5° 36’ N 11° 09’ E; Manki II.river Mvi 5° 51’ N 11° 06’ E; Ngambe, river Kim 5° 46’ N 11° 30’ E«.