Trachycephalus is a genus of frogs, the casque-headed tree frogs, in the Hylidae family. They are found in Mexico, Central America, and South America. In a recent revision, the seven species of the genus Phrynohyas were included in this genus, and Phrynohyas is now considered a synonym of Trachycephalus. These frogs inhabit the canopies of tropical rainforests, where they breed in tree cavities, and seldom, if ever, descend to the ground.