From Boulenger 1909, pp. 105-106:
Depth of body 3 1/5 to 4 times in total length, length of head 4 ½ to 5 times. Head 1 1/5 to 1 1/3 times as long as deep, upper profile descending in a straight or slightly concave line; snout 1/3 to 2/5 length of head; lower jaw with a roundish or oval, depressed dermal appendage about as long as eye; teeth notched, 5 to 10 in upper jaw, 6 to 10 in lower; eye moderate, 1/2 to 2/3 length of snout, ½ to 3/4 interorbital width. Dorsal 28-33, originating above 10th to 15th ray of anal, its length about twice in its distance from head. Anal 36-43, equally distant from base of ventral and from base of caudal. Pectoral pointed, ¾ to 4/5 length of head, more than twice as long as ventral, extending beyond base of latter. Caudal scaled, with long pointed lobes. Caudal peduncle 3 times as long as deep, f to f length of head. 75-80 scales in lateral line, 15-19 / 21-23 transverse series on body, 13-17 / 10-14 in transverse series between dorsal and anal, 12 round caudal peduncle. Uniform silvery.
Total length 450 millim.
The EOD waveform of Marcusenius monteiri has a total duration of 0.35-0.45 milliseconds and is triphasic with a weak head-negative prepulse (P0) followed by a head-positive phase characterized by a slow initial rise and abrupt inflection point, followed by a head-negative spike. Usually the "overshoot" fourth phase is absent or very small.
Congo River Basin and Lake Bangwelu
Common mormyrid caught in large rivers