Diagnosis: Polypterus bichir is characterized by a lower jaw slightly longer than upper jaw and a pectoral fin reaching the first dorsal ray (Ref. 2835, 42908, 81263). The subspecies P. bichir bichir has 63 to 70 scales in lateral line, 14 to 18 dorsal fin rays and 11 to 13 pelvic fin rays (Ref. 367, 81263). The subspecies P. bichir lapradei has 58 to 68 scales in lateral line, 13 to 15 dorsal fin rays and 13 to 16 pelvic fin rays (Ref. 367, 81263).

Description: Polypterus bichir bichir has a subcylindrical body, the height of which is comprised from 6,8 to 10,2 times in its length, head length comprised from 4,1 to 5,5 times in total length (Ref. 2835, 81263). Head slightly flattened, 1,7 to 2,3 times longer than broad; interorbital space plane; lower jaw slightly longer than upper jaw; eye diameter from 8,5 to 13 times in head length (Ref. 2835, 81263). Dorsal fin with 14-18 rays, followed by 19-21 dorsal and caudal articulated rays; anal fin with 13-16 rays; pectoral fin with 38-45 rays and rounded, getting beyond the level of the first dorsal ray; 11-13 pelvic fin rays (Ref. 367, 2835, 42908, 81263). Ganoid scales (Ref. 36900, 42904): 63-70 in lateral line, 46-54 around body and 11-15 predorsal scales; lateral line scales grooved with notched posterior border (Ref. 2835, 42908, 81263). Number of vertebrae 61-62 (Ref. 367). Polypterus bichir lapradei has a subcylindrical body, the height of which is comprised from 6,6 to 11,2 times in its length, head length comprised 4,3 to 5,6 times in total length (Ref. 2835, 81263). Head slightly flattened, 1,5 to 2,2 times longer than broad; interorbital space plane or slightly convex; lower jaw longer than upper jaw; eye-diameter from 8 to 12 times in head length (Ref. 2835, 81263). Dorsal fin with 13-15 rays, followed by 20-21 dorsal and caudal articulated rays; anal fin with 14-15 rays; pectoral fin with 41-43 rays and rounded, getting beyond the level of the first dorsal ray; 13-16 pelvic fin rays (Ref. 367, 2835, 42908, 81263). Ganoid scales (Ref. 41904): 58-68 in lateral line, 46-52 around body and 11-14 predorsal scales; lateral line scales grooved with notched posterior border (Ref. 2835, 42908, 81263). Number of vertebrae 61 (Ref. 367).

Colouration: In alcohol, Polypterus bichir bichir with upper part of body olive-coloured, belly whitish; juvenile specimens with three horizontal dark stripes on the sides, remains of these three stripes may be perceptible in adults; pectoral and ventral fins with transversal bands greenish and yellowish, dorsal and anal fins often spotted with black (Ref. 367, 2835, 81263). In alcohol, Polypterus bichir lapradei with body yellowish or greenish on the upper part, belly clearer, sides often with dark longitudinal stripes; fins spotted with black, scattered dark spots and blotches are sometimes present on the caudal, ventral and pelvic fins and undersides of the belly (Ref. 367, 2835, 13851, 81263).