Diagnosis: outer teeth of jaws in females and young males bicuspid except a few lateral unicuspids, but mature males with many unicuspids, until at about 20cm SL nearly all outer teeth are unicuspid and the posterior are enlarged; pharyngeal teeth fine and dense, with blade of lower pharyngeal bone longer than toothed area; 21-26 gill-rakers on lower part of first arch; 29 vertebrae; 15-16, rarely 17 dorsal spines; total dorsal rays 27 or 28; caudal fin not scaly; genital papilla in both sexes complex, in the male elongate, bifid and tasselled; white spots on pelvic fins of mature males and on dorsal, anal and base of caudal in both sexes; dentition and coloration of mature males diagnostic (Ref. 2).

Description: upper head profile straight; preorbital bone showing very little allometry (Ref. 54192, Ref. 2). Length of jaws showing no correlation with size or sex (Ref. 2). Microbranchiospines on outer sides of second, third and fourth arches; toothed area of lower pharyngeal bone with rounded lobes (Ref. 54192, Ref. 2) and weak posterior notch (Ref. 2). Scales on cheek in 2-3 rows; 4-5 scales between bases of pectoral and pelvic fins (Ref. 54192, Ref. 2), moderately small on chest but not very small on belly (Ref. 54192). Dorsal and anal fin with bases ending at the same vertical, or anal fin a little more posteriorly (Ref. 54192). Pelvic fin produced into a filament reaching vent or origin of anal fin (Ref. 54192, Ref. 2). Genital papilla of male in preserved fishes up to 12mm long, bifid, with tubercles and filaments; papilla of female with uneven edge and shorter filaments (Ref. 2).

Coloration: body grey-brown (Ref. 52307), with dorsal parts darker than ventral parts (Ref. 52307, Ref. 2). Conspicuous white spots on dorsal and anal fins, and usually on base of caudal (Ref. 54192, Ref. 52307, Ref. 2). Similar spots on pelvic fins in larger specimens (Ref. 2). Caudal fin with some dark spots (Ref. 54192). Mature males reddish with a silvery-white spot on each scale on the upper body parts (Ref. 54192, Ref. 52307, Ref. 2) and with posterior dorsal lappets and upper edge of soft dorsal fin red (white when preserved)(Ref. 2). Male with white upper lip and narrow white (red in life) upper edge of soft dorsal fin (Ref. 54192).