If you go trekking through the Western Ghats mountains of India, you probably won’t see one of the region’s most charming residents. That’s because they’re frogs that live underground, only emerging to mate when it’s raining. The frogs, called Bhupathy’s purple frogs, have pig-like snouts, blue rings around their eyes, and glistening purple skin. They were unknown to science until recently, reports National Geographic, when a team of researchers noticed some strange tadpoles swimming in a stream.

Bhupathy’s purple frog tadpoles aren’t like most frog tadpoles. Most tadpoles grow tails and dart around ponds—purple frog tadpoles have mouths that allow them to attach to rocky cliffs behind waterfalls created by monsoon rains, where they hang out and eat algae for about four months. As adults, they live entirely underground, where they eat termites and ants with their long tongues.

A species of purple frog discovered in 2003 is a close cousin of the Bhupathy's purple frog.
A species of purple frog discovered in 2003 is a close cousin of the Bhupathy’s purple frog. Karthickbala/CC BY-SA 3.0

The purple frogs are unique, but they do have a cousin, sometimes called the purple frog, discovered in 2003. The species found in 2003 lives on the western flank of the mountain range and comes out to mate during monsoons from May to August, while the new purple frog lives on the east side and emerges during monsoons between October and December. The two species are closely related, but they’re the only two members of their purple, pig-nosed family.