Diagnosis: Coptodon fusiforme is distinguished from all Tilapia and Coptodon species by the combination of a slender fusiform body, an acute mouth, a pitch black breeding colouration and the 'tilapia spot' being extended to a longitudinal stripe in juveniles (Ref. 85854). It further differs from other Tilapia senso lato except Coelotilapia joka, Congolapia bilineata and all members of Coptodon in tricuspid pharyngeal teeth in the posterior two rows of lower pharyngeal jaw; it differs from Coelotilapia joka in more gill rakers on first ceratobranchial, 10-11 vs. 6-8; and from Congolapia bilineata in a caudal fin not densely scaled (Ref. 85854).
Description: It is a small tilapia with a laterally compressed body; head profile straight (Ref. 85854). Moderately pointed head; snout outline obtuse; eye very large and interorbital width always smaller than eye length (Ref. 85854). Greatest body depth at level of first dorsal spine; dorsal line slightly posteroventrally curved; caudal peduncle always longer than deep (Ref. 85854). Body scales cycloid, chest scales smaller than flank scales and slightly embedded; upper lateral line extending from posterior margin of gill cover to approximately last dorsal ray; upper lateral line separated from first dorsal spine by three to four scale rows; lower lateral line originating at level of first dorsal branched rays and terminates midlaterally on caudal peduncle; one or two scales of lower lateral line extending onto caudal fin; two scale rows between upper and lower lateral line; preoperculum with three to four regular rows; lower one third of pectoral base mostly lacking scales (Ref. 85854). First ceratobranchial with 10-11 gill rakers and first upper gill-arch with 4-5 gill rakers; ceratobranchial rakers slender and pointed; gill raker in angle of arch and first four epibranchial rakers more slender, decreasing in size towards last (Ref. 85854). Origin of dorsal fin at level of origin of pelvic fin; first dorsal spine always shortest, last dorsal spine always longest; longest spines always shorter than longest ray; last dorsal ray most deeply branched; caudal fin outline truncate; third anal spine always longest; tip of longest anal fin ray not overlapping hypuralia; last dorsal ray most deeply branched; tip of longest pelvic-fin ray mostly overlapping anus (Ref. 85854). Jaws isognathous; teeth in upper and lower outer row in both jaws bicuspid; neck of anterior jaw teeth stout, crown expanded and cusps truncated; one to two incomplete inner rows of smaller tricuspid teeth in both jaws; lower pharyngeal jaw as long as broad, anterior keel shorter than toothed area; posterior pharyngeal teeth tricuspid, stout, slightly hooked and regularly arranged, especially over posterior third of toothed area; dentigerous plate triangular; most teeth in anterior two thirds of toothed area approach the 'kukri' tooth shape (Ref. 85854).
Colouration: Non breeding colouration in alcohol: basic colouration light brown; dorsal side brown, darker than on ventral side; upper lip dark coloured, lower lip pale; cheek and operculum light brown; belly light brown; seven to eight indistinct dark vertical bars on dorsum and sides, first bar at level of first dorsal spine, the last two on caudal peduncle; operculum spot indistinct; all fins transparent, 'tilapia spot' extended to a longitudinal stripe, especially in juveniles (Ref. 85854). Breeding colouration in alcohol: basic colouration dark brown to blackish; dorsal parts brown to blackish, darker than the ventral side; lips dark; cheek and operculum pale; ventral parts with some pale areas; entire body dark, no vertical bars; operculum spot indistinct; pectoral fins transparent; pelvic fins transparent or slightly blackish; anal fin dark brownish to blackish, margins transparent; caudal fin dark brownish to blackish and margins transparent; dorsal fin dark brownish to blackish, margins transparent, 'tilapia spot' not always visible; if present, then extended to a longitudinal stripe, especially in juveniles (Ref. 85854). Non breeding colouration in life: basic colouration chartreuse greyish, chest bright yellow and belly pale; head slightly darker than body and more green; upper lip bluish green and lower lip whitish; a horizontal iridescent blue line above antero-rostral margin of preopercle; iris of eyes brown to slightly reddish; body with indistinct slightly blackish vertical bars and a nape band; opercular spot indistinct; all fins bright yellow; in soft part of dorsal fin 'tilapia spot' extended to a longitudinal stripe (Ref. 85854). Breeding colouration in life: basic colouration dark brown to blackish, especially on head, blackish colouration on chest and ventral side interrupted by pale areas; lips dark brownish; lower side of head with some pale areas; iris of eyes slightly dark red; no vertical bars; pectoral fins transparent; pelvic and anal fin slightly yellow with black blotches and black base; base of caudal fin completely dark, margins yellow with blackish blotches; base of dorsal fin black, margins yellow with blackish blotches; operculum and 'tilapia spot' not visible (Ref. 85854).