Campylomormyrus tamandua (Günther, 1864)
Species overview
Large fish, moderately elongate, head trunk-shape snouted, snout moderately long, compressed, inclination about 30°. Greyish blackish, juveniles lighter, with dark bar between unpaired fins. Size observed: 430 mm SL.
C. tamandua(measurements)
Taxonomic description
-Body moderately elongate, laterally compressed, body depth 23-26 % SL, greatest depth close to anal fin.
-Head short, about 17-19 % SL, measured without snout, 27-31 % SL snout inclusive, head depth 16-20 % SL, 68-75 % body depth. Back straight to slightly convex, belly slightly convex, upper profile of head convex, underside of head concave.
-Snout or rostrum moderately long, compressed, not much extending over deepest point of belly, 130-160 % postorbital length, its least depth nearly equals diameter of eye. (The extreme shape of the snout changes with age/size of the fish, in juveniles it is much less obvious).
-Mouth directed forward, edge of mouth very far away from anterior nostril, upper jaw well below head.
-Chin with submental swelling and compressed barbel about as long as eye diameter.
-Teeth conical, 2-4/3-4.
-Nostrils separate, anterior circular, posterior oval, both in front of eye at a level with its lower rim, anterior somewhat above and as far away from front contour as from posterior nostril; distance posterior nostril to eye equals eye diameter; axis of nostrils cuts axis of head at an angle of about 30°.
-Eye moderately large, about 33 % postorbital length.
-Opercular cleft about 40 % head depth, straight.
-Dorsal fin 26-31, anal fin 29-35 fin-rays, base of D 22-26 % SL, base of A 26-31 % SL, D originating behind origin of A, ending before end of A. Predorsal length 58-64 % SL, preanal length 54-60 % SL.
-Pectoral fin pointed, originating close to middle of opercular cleft, extending to middle of pelvic. V is closer to P than to A.
-Caudal pointed, scaled portion short, pointed. 70-84 scales in lateral line, 12 round caudal peduncle. Length of caudal peduncle 14-17 % SL, its depth 4-5 % SL, 27- 32 % its length.
-Coloration In adults uniform greyish - blackish, fins with dark markings. Juveniles, below 200 mm, are lighter, with a dark rhomboid band between anterior parts of D and A, bordered white and continuing on the fins. Posterior parts of D and A brighter, so are the median rays of the lobes of C.
Type locality
»West Africa«
Distribution
Volta-, Niger-, Chad-, Shari- and Congo basins.
Electric organ discharges
Biphasic, head positive, +/- with low negative precursor.
C. tamandua(EOD)