Diagnosis: Small ‘Lampeye’ with relatively long fins; dorsal, anal and caudal fins of the male trapezoid, upper lobe of caudal fin enlarged; ventral fins with extremely long second and third rays that may reach to the caudal fin base; dorsal-fin with 6-8 rays, anal fin with 12-14 rays; first dorsal fin ray above or just behind last anal fin ray; scales on mid-longitudinal series 24-27 (Ref. 57259).

Colouration: Male colouration: body is yellow-grey to pale olive, the ventral area being silver; the sides with a light blue iridescence of dust fine spots; the iridescence is most intense on the anterior part of the side; iridescent spots not arranged in horizontal lines or bands; scales on the back and the upper parts of the sides with a narrow dark grey margin, producing a weak reticulation; dorsal fin is very pale yellow to transparent with rows of dark red-brown spots; anal fin very pale yellow to transparent with horizontal rows of dark red-brown spots; the caudal fin is pale yellow with curved rows of dark red spots; two colour phenotypes can be identified, a white and an orange, according to the colour of the margins at the dorsal and anal fin, upper and lower caudal fin and the colour of the extended ventral fins; in the adult male the ventral fins may extend to the end of the caudal peduncle (Ref. 57259). Female colouration: translucent pale grey with silver abdominal region; some small golden spots may be present on the sides, usually on or near the mid-lateral line; scales on the sides have very narrow grey edgings; all fins are colourless, ventral fins not extended (Ref. 57259). Both sexes have a distinct reflective blue spot in the upper part of the iris (Ref. 57259).