Glass frogs include more than 120 species in three genera (Centrolene, Cochranella, and Hyalinobatrachium). They occur from tropical lowland forests (tropical rainforest) to mid-elevation mountain forests. Most species are small, with adults ranging from 20 to 30 mm (0.8 to1.2 inches) in total length. In a few species adults are larger, attaining a maximum length of nearly 80 mm (3 inches).

For mating to occur, males must first call to females. Calling males sit on leaves (leaf)—either the top or underside depending upon the species—over streams or lake edges. When a female comes, she does not descend to the water with the amplexing male. Instead, they mate on the calling leaf where she deposits her eggs. After she departs, the male often remains to protect the eggs from predators and call additional females. Some males will attract other females and thus have several egg clutches in various developmental stages to guard. When the tadpoles (tadpole) hatch, they fall into the water below. Tadpoles usually live and feed amidst the leaf litter and stream-side detritus until they metamorphose into froglets. One of the major egg predators are “frog flies,” which lay their eggs on the egg masses. The flies' (fly) eggs hatch quickly, and the maggots feed on the frog embryos (embryo).