Stomatorhinus microps Boulenger, 1898
Species overview
Small fish, body elongate, moderately deep, head longer than body depth and head depth, snout rounded or slightly truncate, clearly protruding mouth which is definitely subterminal; caudal peduncle deep. Coloration see below. Size observed: 83 mm SL, 95 mm TL.
S. microps(measurements)
Taxonomic description
-Body elongate, laterally compressed, cross section oblong-oval, body depth 22-26 % SL, greatest depth at about middle of body.
-Head length 28-31 % SL; head depth 17-22 % SL, 76-93 % body depth.
-Outlines of back more or less straight, outline of belly slightly convex, upper profile of head convex, underside of head concave.
-Snout truncate to slightly rounded, 16-27 % head length, 24-41 % postorbital length.
-Mouth width 14-20 % head length, subterminal, its edge below anterior rim of eye, upper jaw on a level between origin of pectoral fin and underside of head.
-Chin inconspicuous.
-Teeth notched, 7/8.
-Nostrils clearly separate, posterior nostril oval, anterior on a level slightly below lower rim of the eye, posterior nostril close to edge of mouth.
-Eye very small, its diameter 4-8 % head length, 6-13 % postorbital length.
-Opercular cleft slightly curved 22-31 % head length, 36-48 % head depth.
-Dorsal fin 18-20 fin-rays, base of D 21-24 % SL, anal fin 20-22 rays, base of A 21-26 % SL, origin of D behind origin of A, end of D more or less opposite to end of A; predorsal length 61-67 % SL, preanal length 57-64 % SL.
-Pectoral fin obtusely pointed, reaches to middle of pelvic fin or slightly beyond. V is closer to P than to A.
-Caudal fin rounded, the scaled lobes rounded, extending over about 1/4 the length of the fin. 48-53 scales in lateral line, only 46-50 with pores; 16-18 scales round caudal peduncle.
-Caudal peduncle short, 11-15% SL, its depth 6-7 % SL, 42-55 % its length.
-Coloration »Colourless«. (The original description does not indicate whether this refers to live or preserved specimens. All other species of Stomatorhinus are brown to black in colour.)
Type locality
»Boma Matadi (Bas-Congo) et région des Cataractes (Manyanga)«. (Boma: 5° 51 ‘ S 13°03 ‘ E; Matadi: 5° 49 ‘ S 13° 27 ‘ E.) District Bas-Zaïre, Democratic Republic of Congo.
Distribution
Lower Congo basin, Democratic Republic of Congo, probably south-western part of Rep. Congo Brazzaville, north-western part of Angola (Cameroon?).