Hylidae are a family of frogs with tree dwelling adaptations, and include several species commonly called "treefrogs and their allies". However, the hylids include a diversity of frog species, many of which do not live in trees, but are terrestrial or semi-aquatic.
Hylids mostly feed on insects and other invertebrates, but some larger species can feed on small vertebrates.
Hylids lay their eggs in a range of different locations, depending on species. Many use ponds, or puddles that collect in the holes of their trees, while others use bromeliads or other water-holding plants. Other species lay their eggs on the leaves of vegetation overhanging water, allowing the tadpoles to drop into the pond when they hatch.
A few species use fast-flowing streams, attaching the eggs firmly to the substrate. The tadpoles of these species have suckers enabling them to hold onto rocks after they hatch. Another unusual adaptation is found in some South American hylids, which brood the eggs on the back of the female, with Hemiphractus species going as far as to enclose the eggs in a pouch until they hatch. The tadpoles of most hylid species have laterally placed eyes, and broad tails with a narrow, filamentous, tip.
In North America, there are many species of the Hylidae family, including Hyla versicolor (the grey tree frog) and Hyla cinerea (the American green tree frog). The spring peeper (Pseudacris crucifer) is also widespread in the eastern United States and is commonly heard on summer and spring evenings.
"Tree frog" is a popular name for several of the Hylidae. Hyla versicolor is the changeable tree frog, Trachycephalus lichenatus is the lichened tree frog, and Trachycephalus marmoratus the marbled tree frog. However, the name "treefrog" is not unique to this family, also being used for many species of the Rhacophoridae.