Diagnosis: dorsal profile rounded; territorial males uniformely blue; egg spots on anal fin absent or strongly reduced; melanin pattern of females and non-territorial males with vertical bars, often connected ventrally; spots on flanks present (Ref. 55929).

Description: head relatively large; dorsal profile rounded, ascending above pectoral fins and descending progressively after the pectorals; frontal profile concave, especially in males; mandibular, lachrymal and preopercular cephalic pores well developped; outer oral jaw teeth conic, with outer row teeth enlarged; lower pharyngeal jaw teeth conic, curved forwards; upper part of lateral line, with 26-31 scales, sometimes reaching caudal peduncle but not extending onto caudal fin; lower part of lateral line, with 14-18 scales, continues on caudal fin for about 3 scales (Ref. 55929).

Coloration: In life: Territorial males: body, head and fins blue; caudal fin with radiating yellow striae; lower flanks slightly yellow, especially close to the caudal fin; dorsal fin with white margin and black submarginal band; pelvic fins with white edge; anal fin blue, with fin spots absent or strongly reduced; eye reddish brown (Ref. 55929). Juveniles, females and non-territorial males: 6-8 dark vertical bars, sometimes fused or V-shaped; 2-3 spots on flanks, of which 1 is situated on the caudal peduncle; females sometimes dark brown, depending on emotional state and light conditions, and with whitish round or elongated spots on the unpaired fins (Ref. 55929). In alcohol: body dark grey-brown, males almost black; unpaired fins often with white margin; females with round white spots on soft part of dorsal and anal fins; 6-8 vertical bars, of which 5 are situated below the dorsal fin (Ref. 55929).