Heteromormyrus tavernei
Description from Poll (1972) translated by J. Sullivan
Measurements from the holotype given first, those of the paratypes in parentheses.
In % of standard length. – Body depth 23.5 (22.2-24.2), head length 25.8 (25.8-29.2), head depth 18.9 (18.9-22.5), caudal peduncle length 17.7 (16.4-21.1), caudal peduncle depth 7.7 (6.9-8..6), dorsal fin length18.3 (15.2-19.1), anal fin length 22.3 (19.3-22.3), pectoral fin length 17.6 (17.2-20.9), ventral fin length 9 (8.8 -11.8), caudal fin length 15.8 (15.8-18.4), predorsal distance 47 (41.3-47), pre-anal distance 19.7 (18-22).
In % of head length. Head depth 73.5 (70.7-7.8.7), eye diameter 12.6 (12.4-16.7), snout length 30 (24.7-30), interocular distance 27.9 (24.7-30), postorbital distance 61.5 (57-65.4), distance between gill openings 33.2 (30.7-34.7), mouth width 17.4 (15.3-17.7).
In % of the snout length. – Eye diameter 42.2 (42.2-64.8), interocular distance 93.1 (93.1-127), postorbital distance 204.9 (204.9-243.2), distance between the 2 nostrils 18.6 (17.9-22.2), mouth width 57.8 (55.7-63).
In % of the postorbital distance. - Eye diameter 20.6 (20-27.8), interocular distance 45.5 (41.1-60), snout length 48.8 (42.2-50).
In % of the interocular distance. - Diameter of the eye 45.3 (43.3-51).
In % of the body depth. - Dorsal fin height 43.5 (43.5-60.5), anal fin height 41.6 (40.4-60.5), head depth 80.6 (80.6-93.3), caudal peduncle depth 32.6 (29.7-36.1), caudal peduncle length 75.2 (68.9-88.1).
Caudal peduncle depth 43.3 (36.1-45.8)% of its length. Dorsal length 38.9 (33.4-44.7)% of the predorsal distance. Anal length 113.1 (88.2-113.1)% of the pre-anal distance.
Dorsal rays 19 (17-20). Anal rays 23 (22-23). Scales in lateral line 72 (70-77), 15/13 (14-15/13-16) in transverse line 22 (20-22) around the caudal peduncle. Teeth 9/9 (6 -9/8-10).
Color. - Uniform dark brown, a little lighter beneath, with a transverse darker band between the median fins, near their origin. Fins also brown.
Affinities. - L. TAVERNE reports 6 species to this new genus but none resembles the new species. They differ either by the numbers of scales along the longitudinal line, and all by the numbers of scales around the caudal peduncle, always many fewer than 20. The number is in the case of Brienomyrus tavernei, particularly high, related to the exceptional thickness of the peduncle.