Hyalinobatrachium pellucidum, also known as the Rio Azuela glass frog, is a species of frog in the Centrolenidae family. The frog is named for its skin which is translucent to the point that internal organs and surfaces immediately behind the frog can be seen. The reason for this is lack of pigmentation. This frog is about the size of a fingernail: males measure 20–22 mm (0.79–0.87 in) and females about 22 mm (0.87 in) in snout–vent length. It is found in lower montane rainforests on the Amazonian Andean slopes in Ecuador and Peru. Its natural habitats are tropical moist mountains and rivers. It is threatened mostly by habitat loss, although conservation programs have begun to help save this interesting creature.