The glass frogs belong to the amphibian family Centrolenidae, native to the Central American Rainforests. The general background coloration of most glass frogs is primarily lime green, the abdominal skin of some members of this family is transparent and translucent, giving the glass frog its common name. The internal viscera, including the heart, liver, and gastrointestinal tract, are visible through the skin. When active their blood makes them visible; when sleeping most of the blood is concealed in the liver, hiding them. Glass frogs are arboreal, living mainly in trees, feeding on small insects and only coming out for mating season. Their transparency conceals them very effectively when sleeping on a green leaf, as they habitually do. However, climate change and habitat frangmentation has been threatening the survival rates of the family.
Glass frog
Cochranella albomaculata from Costa Rica
Cochranella granulosa from Costa Rica
A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura. The oldest fossil "proto-frog" Triadobatrachus is known from the Early Triassic of Madagascar, but molecular clock dating suggests their split from other amphibians may extend further back to the Permian, 265 million years ago. Frogs are widely distributed, ranging from the tropics to subarctic regions, but the greatest concentration of species diversity is in tropical rainforest. Frogs account for around 88% of extant amphibian species. They are also one of the five most diverse vertebrate orders. Warty frog species tend to be called toads, but the distinction between frogs and toads is informal, not from taxonomy or evolutionary history.
Frog
Variegated golden frog (Mantella baroni) in the Ranomafana National Park of Madagascar
European fire-bellied toad (Bombina bombina)
Panamanian golden frog (Atelopus zeteki)