निदान |
Diagnosis: A large deep-bodied tilapia, with a relatively small head (Ref. 118638). Jaws of mature male not greatly enlarged, length of lower jaw 29-37% of head length; genital papilla of breeding male not tassellated (Ref. 2). Body depth 36-50% of SL (Ref. 28714). Most distinguishing characteristic is the presence, at all life stages, of regular vertical stripes throughout depth of caudal fin (Ref. 4967, 53405, 118638). In smaller fishes, these are relatively wide and form an arc, and start at the base of the caudal fin (Ref. 118638). Males are bluish pink, sometimes with a dark throat, belly, anal and pelvic fins; females are usually brownish, silvery/white beneath with around 10 thin vertical bars (Ref. 118638).
Description: Lower pharyngeal bone longer than broad, its anterior part longer than toothed part; outer jaw teeth bicuspid, inner jaw teeth tricuspid, posterior pharyngeal teeth bicuspid and stout; 3-4 rows of teeth in jaws (3-5, rarely 6, in specimens over 200 mm SL); micro-gillrakers present; scales cycloid (Ref. 53405).
Coloration: margin of dorsal fin grey or black; vertical bars in caudal fin 7-12 (Ref. 2). Regular black cross bars on caudal fin; ground colour greyish, relatively dark in adults; back olivaceous-green, sides paler, with 6-9 rather indistinct cross bars; belly whitish; upper lip pale green or white, lower lip white; dorsal and anal fins greyish, sometimes with very narrow red margin, soft part of fin with vertical lines (or with aligned light spots resembling striped pattern); pelvic fins grey, pectorals transparent; "tilapian" spot lacking in adults but very distinct in fingerlings which also have more distinct cross bars and very prominent black spot on upper part of caudal peduncle; throat, belly and unpaired fins black in mature males (Ref. 53405). Head and trunk in breeding male suffused with red (Ref. 28714). |