Family: TRIPTERYGIIDAE, Triplefins
The triplefins are small (usually 3-5 cm), elongate fishes; head robust, pointed; cirri at nostrils and over eyes but not on nape; top jaw protractile; upper and lower jaws with a wide band of conical teeth; dorsal fin in three parts, fin divided to body between them: III-IV+VIII-XIX + 8-12; anal fin 0-II, long base; pelvics I (imbedded), 2, inserted just before pectoral base; tail fin 13, 9 rays branched; scales usually rough; lateral line continuous and curved down, or in 2 parts, scales on front part with pores, those on back part with notches.
Triplefins are relatively inconspicuous inhabitants of tropical and temperate reefs. Many of the species are cryptically coloured or semitransparent; this, in combination with their small size, often makes them difficult to detect. They dwell on the reef"s surface, often in weedy areas, on algal-covered rocks, or on rubble. Their food consists primarily of tiny invertebrates living in algae.
The family occurs worldwide, but most of the estimated 145 species in 30 genera occur in the Indo-Pacific. In our region there are 15 species, all endemics, in four genera, one of which is endemic.