Diagnosis: Oreochromis upembae is a deep-bodied species with a short head, which looks very similar to O. malagarasi (Ref. 52307). It is distinguished by following characters: mature males with a bifid and tuberculate genital papilla, prolonged into a cream-coloured tassel in breeding males, in which the edges of the dorsal and caudal fins are orange-coloured or red; two to four dark blotches mid-laterally from operculum to caudal peduncle and a blotch on top of caudal peduncle, distinctive in that the blotches are rather large and vaguely outlined and persist in adults; caudal fin with dark, narrow, vertical stripes or series of spots, only a little less regular than in O. niloticus; caudal rays rather densely scaled to near edge; caudal peduncle deep; vertebrae 29-30; scales in lateral line series 28-31; dorsal spines XIV-XVI, soft rays 11-13; outer teeth bicuspid, in some fishes becoming unicuspid by wear; lower pharyngeal teeth fine, the tooth area with rounded lateral lobes, the blade 1.15-1.5 times the medial length of the toothed area; lower gill-rakers 20-25; and interorbital width 38.8-43.3% length of head (Ref. 2). Among the tasselled tilapias this most resembles O. malagarasi, which differs in having a less scaly caudal fin, the scales usually confined to the basal parts of the rays, and in lacking the regular dark stripes or series of spots on the caudal; and in O. malagarasi the range of dorsal spines is higher, XVI-XVII (Ref. 2).

Description: A deep-bodied species with a short head (Ref. 2).

Colouration: Body colouration is dark brown with some yellow on the flanks; the throat and breast are black; some dark maculae may be visible on the flanks; the fins are normally dusky gray and the dorsal fin exhibits red margins; some reddish vertical bars are normally present in the caudal fin (Ref. 52307).