Distribution:
All tropical and occasionally temperate seas, rarely in brackish water.
Habitat:
Usually associated with coral or rocky reefs, infrequently over soft bottom and seagrass beds, in depths less than one meter to over 200 m.
Remarks:
Damselfishes are unusual within the Perciformes in almost always having a single pair of nostrils and two anal-fin spines.
All members of this family use labriform locomotion and primarily use their pectoral fins for swimming. They are quite territorial and can be aggressive to divers, though the largest species is roughly on 35 cm. Males generally build nests and guard the eggs until hatching. They display remarkable diversity of coloration, ranging from dull brown, gray, and black to brilliant combinations of blue, yellow, and orange, and many are in the aquarium trade.
There are 28 genera and approximately 348 species in four subfamilies, although the status of some subfamilies is tenuous.
References:
Allen, pp. 3337-3356, in: Carpenter & Niem 2001;
Carter & Kaufman, pp. 1694-1700, in: Carpenter 2002;
Nelson 2006