Threadfin cardinalfish

Scientific name : Apogon leptacanthus

A quite small (maximum length: 6,0 cm) fish, with a transparent-yellow base color; shows three bright blue vertical bands, on its sides, from the operculum to the last ray of the first dorsal fin.
It forms dense aggregations, even with fish of different species, above mounds of branching corals in sheltered bays and lagoons, even in turbid waters. Nocturnal.