The microscopic tardigrades can be found in almost any habitat on Earth ( Credit: Ralph O. Schill/European Space Agency)

Tardigrades, or water bears, are virtually indestructible. The eight-legged microscopic animals can withstand extreme temperatures, survive without food for decades, and even exist in a vacuum in space. But, despite being around for over 500 million years, they rarely appear on the fossil record. Their miniature size and lack of hard tissue make it hard for them to fossilize. Even when they do get preserved, the tiny creatures are hard to spot and often get overlooked. Over the years, only two tardigrade fossils have been found. Now, a third specimen — one of a new tardigrade species — has joined this exclusive group.