Close_up of a glass frog larva tadpole developing in its egg, eight days after being laid. The glass frog is so named due to its translucent skin, through which internal organs can be seen. Its heart is seen beating beneath its skin, and blood cells are seen moving in the large vessel in its chest. Dark areas of pigment are also seen. Glass frogs family Centrolenidae inhabit moist tropical forests in Central and northern South America. They typically lay their eggs on a leaf above water, so that the tadpoles fall into the water as soon as they hatch. Filmed in the Ecuadorian Amazon.