Diagnosis: slender, gracile lower pharyngeal jaw with a narrow, elongate keel; 17-19 gill-rakers on lower limb of first arch; entire premaxillary oral flap; mature males with a prominent oblique band behind the head (Ref. 52346).
Description: juveniles (<8cm SL) relatively slender and gracile, adults extremely deep bodied and rotund (Ref. 52346). Predorsal profile rises steeply over the snout (Ref. 52346, Ref. 52307) but is usually interrupted by a thickening in the interorbital region, and rises sharply again in a broad sweep to the origin of the dorsal fin; deepest body depth along the back lies at, or a little behind, the dorsal fin origin; lower jaw more or less horizontal when closed, but may be slightly inclined in the larger individuals; lips extremely thick and fleshy; lower pharyngeal jaw slender and gracile; vertebral apophysis borne on the third and fourth vertebrae and of the standard Tylochromis type; highly crenate, closely overlapping rakers along the lower limb of the first arch; epibranchial rakers elongate; 35-37 lateral line scales; upper branch of lateral line terminates a little in advance of the end of the soft dorsal, usually below the fourth or fifth ray from the free end of the fin; terminal canal bearing pores rarely descend scale rows; dorsal, ventral and median branches of the lateral line on the caudal fin are well developed and extend almost to the fin periphery; dorsal fin spines increase in length to the fifth or sixth, and are then more or less equal in length; anal fin rounded; pectoral fin relatively short, rarely reaching the origin of the anal fin; first branched pelvic ray produced and filamentous, sometimes extending well beyond the anal fin in males, reaching along the soft anal in females; caudal fin roundly emarginate and densely scaled almost to the periphery, even in small individuals (Ref. 52346). Caudal fin moderately subtruncate (Ref. 52307).
Coloration: adult male: greenish bronze along the dorsum becoming light silvery green on the flank, cheek and caudal peduncle (Ref. 52346). Each scale edged with black (Ref. 52346, Ref. 52307), and pigmented scale edges aligned such as to lend the impression of numerous longitudinal striations (Ref. 52346). A broad pale band interrupts these striations just behind the head, traversing the side of the fish and going down obliquely from the region just behind the nape to the base of the pelvic fins; chest and belly light yellow; branchiostegal membranes, lower lip and upper lip fold membranes white; upper lip black; ethmoidal, interorbital and cheek regions dark greenish black and just anterior to the black nape band is a small region of dark brownish gold; dorsal and anal fins dark smokey grey and spotted by numerous pale creamy maculae (Ref. 52346). Caudal fin pale yellow and streaked with numerous black longitudinal stripes (Ref. 52346), often with a dark spot at the anterior end (Ref. 52307). Pectoral and pelvic fins light smokey grey/brown (Ref. 52346). Female fish: similar in coloration, but somewhat less strikingly marked and paler (particulary on the cheek); dorsal fin strongly maculate, but only faint traces of a few maculae on anal fin; caudal fin dark grey without longitudinal striations; female lacks strong brownish golden region just anterior to the nape band, and the pale oblique band so striking in males is barely discernible (Ref. 52346). Mature females with a streak of red from the corner of the mouth across the cheek (Ref. 52346, Ref. 52307). Both sexes with only faint traces of vertical striping; preserved juveniles often with traces of 5-6 vertical bands (Ref. 52346).