; subclass Actinopterygii, order Perciformes)
A large family of mainly marine fish, none more than 20 cm long, that have two separate dorsal fins and relatively large eyes and mouth. Most cardinal fish display the unusual habit of buccal incubation. In some species the males are the mouth-brooders, in others the female performs this duty. There are about 170 species. They are shallow-water fish of all temperate and tropical seas.
Subjects: Zoology and Animal Sciences.