Diagnosis: peculiar in having only one fine scale on each side of the base of the anal fin; well developed parietal fontanel (Ref. 2880, 81279).

Description: premaxilla with a total of 16 conical teeth aligned in single row; mandible with 20-24 conical teeth, also in single row; anal fin with 2 unbranched and 9-10 branched rays; sexual dimorphism affecting coloration and anal-fin shape (Ref. 2880, 81279): males with rounded anal fin while females with pointed anal fin (Ref. 2880).

Coloration: males with translucid yellow body; at least a dozen brown spots; posterior and caudal-fin lobes tinged with violet; violet transverse stripe on anal and pelvic fins; tiny melanophores on back; no concentration of melanophores along anal-fin base in males; females same colour but without dark spots; melanophores scattered over entire body and fins, but concentrated along anal-fin base, tips of anterior anal-fin rays and on caudal-fin lobes (Ref. 2880, 81279).