As their common name suggests, these tiny frogs appear as though they’re made out of glass. Glass frogs are found in rain forests across Central and South America, and spend most of their lives in trees (as they are arboreal).

As pictured above, their bellies really do seem to be made out of glass. Scientists still haven’t been able to put their finger on why these frogs evolved their translucent undersides, or exactly what the evolutionary advantage for it is. They are incredibly clear, and incredibly tiny, most species of glass frogs don’t grow over two inches.

These animals have a very unique apperance all around, but there’s one thing (aside from their glass bellies) that sets them apart from other frog species. Unlike most other frogs and toads, glass frogs have their eyes positioned facing forward. Most other frogs have eyes on the sides of their head to give them better peripheral vision. They really are interesting creatures that break a lot of rules of fitness in the natural world. This is another adaptation scientists are still puzzled about.

In 2015, a new species of glass frog was discovered in Costa Rica. It’s scientific name is Hyalinobatrachium dianae, but it is more commonly known as Diane’s Bare-hearted glass frog. The most exciting thing about the discovery of this frog: it looks just like Kermit.

Not only are they transparent, tiny, have eyes on the front of their heads, and look like live-action Kermit, but there are some species of glass frogs that make some of the best parents in the animal kingdom. Females lay their eggs on leaves, the eggs are surrounded by a protective jelly to keep them from drying out (as they are not laid in a body of water the way most terrestrial frogs lay their eggs). The mothers will sit on their eggs for the first few hours and keep them protected, but shortly after the males take over, and they make amazing fathers. As mentioned before, these frogs reside in the rainforest of Central/South America, which are densely populated by many other animals (particularly wasps) who would love to make a snack out of their eggs. Glass frog fathers risk a lot to keep their eggs safe from predators, they’ll face off with wasps to protect their young, going as far as to kick, and throw wasps away from their eggs. Now that’s some dedication.

To summarize, these tiny, see-through frogs have nothing to hide, look like everyone’s favorite muppet, and are amazing parents. There are many kinds of glass frogs, all equally interesting, and all equally cute. It’s very likely that there are even more of these frogs we have yet to discover, due to their small size and living high in the trees of some of Earth’s most dense rain forests. Only fieldwork will tell how many species of these animals we have yet to meet.