It is the most widespread and successful of all the trogons. The family Trogonidae includes the trogons and quetzals. The family Trogonidae includes trogons and quetzals. It has a long fluffy tail which is unique amongst trogons. This is found only in trogons. The nests of trogons are thought to usually be unlined. The position of the trogons within the class Aves has been a long-standing mystery. The majority of trogons are birds of tropical and subtropical forests. The fossil record of the trogons dates back 49 million years to the Early Eocene.