The amphibian with transparent skin that can reveal its internal organs is the glass frog.
Glass frogs are members of the family Centrolenidae, a group of small tree-dwelling frogs found mainly in the rainforests of Central and South America. Their common name comes from the translucent or transparent skin on the underside of the body. Through it, observers may see the heart, liver, digestive tract, and other internal organs.
Most glass frogs are not completely transparent from every angle. Their backs are often green and opaque, while the belly and parts of the legs are clearer. This partial transparency helps them blend into leaves above streams, where many species rest and breed. Scientists describe the camouflage effect as “edge diffusion”: translucent limbs soften the frog’s outline against the foliage.
Glass frogs have another unusual adaptation. When resting, some species can move much of their red blood into the liver, making the body even less visible. During activity, the blood returns to circulation. Their transparency distinguishes them from marsupial frogs, which are known for back pouches, and from poison dart frogs, which are famous for vivid warning colors and toxic skin compounds.