The trogons and quetzals are birds in the order Trogoniformes /troʊˈɡɒnɪfɔːrmiːz/ which contains only one family, the Trogonidae. The family Trogonidae contains 49 species in seven genera. The fossil record of the trogons dates back 49 million years to the Early Eocene. They might constitute a member of the basal radiation of the order Coraciiformes and order Passeriformes or be closely related to mousebirds and owls. The word trogon is Greek for "nibbling" and refers to the fact that these birds gnaw holes in trees to make their nests.
Trogons are residents of tropical forests worldwide. The greatest diversity is in the Neotropics, where four genera, containing 34 species, occur. The genus Apaloderma contains the three African species. The genera Harpactes and Apalharpactes, containing twelve species, are found in southeast Asia.