See text Threefin or triplefin blennies are blenniiforms, small percomorph marine fish of the family Tripterygiidae.

Found in tropical and temperate waters of the Atlantic, Pacific and Indian Oceans, the family contains about 150 species in 30 genera.

Many threefin blennies are brightly coloured, often for reasons of camouflage; these species are popular in the aquarium hobby.

As demersal fish, threefin blennies spend most of their time on or near the bottom on coral and rocks.

Threefin blennies are diurnal and territorial; many species exhibit sexual dichromatism, with the females drab compared to the males.