Glass frogs are a group of tree frogs found in the New World tropics.
They live in montane cloud forests of Central and South America, although some species occur also in Amazon and Chocóan rainforest and semideciduous forests.
More than 120 species exist within this family of translucent-skinned tree frogs.
While the general background coloration of most glass frogs is primarily lime green, the abdominal skin of some members of this family is transparent. In those species an observer can see the heart pumping blood into the arteries and food moving through the gut. This is the reason for the common name. There is no satisfactory explanation for this transparency.
Their patterning ranges from uniform green to green with white to yellow spots that mimic glass frog eggs.
Glass frogs are generally small, ranging from 1.9 to 7.6 centimeters (0.75 to 3 in) in length.
They have expanded digit tips that aid in climbing, and this trait allows most to live in trees or shrubs along forest streams.
Glass frogs are mostly arboreal. The word arboreal comes from the Latin arboreus, which means “pertaining to trees.” It’s a word that refers not just to animals that live in trees, but also to anything that resembes the branching form of a tree — like a chandelier or a family geology drawn out.
Glass frogs are nocturnal and spend their days hidden under leaves and among branches.
The feeding behavior of glass frogs is not well studied, but they appear to primarily eat small insects and arthropods. Glass frogs have been observed hunting insects in the dense vegetation beside tropical rivers. In captivity, glass frogs are fed fruit flies.
They are territorial animals, and will make a noise to ward off other animals.
Mating usually takes place after rainy season, or during the light showers. Female lays between 20 and 30 eggs on the underside of the leaves that hang above the water.
Parental care is common, perhaps even ubiquitous among glass frogs, and males sometime guard multiple clutches. Small clutches of eggs are laid above the water on leaves, rocks, or bromeliads. When the type IV tadpoles hatch, they fall into the water below, and live in the muck and leaf litter on the bottoms of streams. Tadpoles living in oxygen-poor habitats are sometimes bright red as a result of blood flow close to the surface of their unpigmented skin.
Average lifespan of glass frog is usually between 10 and 14 years in the wild.
Due to their small size, glass frogs are easy target for many predators including snakes, mammals and birds.
Two species of glass frogs reflects near-infrared light when examined by infrared color photography. Infrared reflectance may confer adaptive advantage to these arboreal frogs both in thermoregulation and infrared cryptic coloration.