As suggested by their name, microhylids are mostly small frogs. Many species are below 1.5 cm (0.59 in) in length, although some species are as large as 9 cm (3.5 in). They can be arboreal or terrestrial, and some will even live close to water. The ground-dwellers are often found under leaf litter within forests, occasionally venturing out at night to hunt. The two main shapes for the microhylids are wide bodies and narrow mouths and normal frog proportions. Those with narrow mouths generally eat termites and ants, and the others have diets typical of most frogs. Egg laying habits are highly varied.
Frogs from Microhylidae occur throughout the tropical and warm temperate regions of North America, South America, Africa, eastern India, Sri Lanka, Southeast Asia, through New Guinea and Australia. Although most are found in tropical or subtropical regions, a few species can be found in arid or nontropical areas. They are the majority frog species in New Guinea and Madagascar.