Fossils discovered in Brazil show that an ancient group of animals survived for much longer than realised.

When researchers digging on the edge of the Amazon rainforest came across an unusually twisted jawbone, they didn’t know what to make of it. However, after eight more turned up over the course of the dig they knew that these fossils weren’t just damaged bones but signs of a new species.

The team have now named this animal Tanyka amnicola, which roughly translates as ‘jaw living next to the river’. It’s thought that the teeth jutting out from its bent jawbone were probably used to grind up plants or small invertebrates, setting it apart from its meat-eating relatives.

Most of these animals, known as stem tetrapods, were long extinct when Tanyka lived 275 million years ago. They’d gradually been replaced by more advanced tetrapods that included the ancestors of living amphibians, reptiles, birds and mammals.

Dr Jason Pardoopens in a new window, the study’s lead author, says that the existence of Tanyka so late in the history of life on Earth is surprising.

“Tanyka is a little like a platypus, in the sense that it was a member of the stem tetrapod lineage that remained even after newer, more modern tetrapods evolved,” Jason says. “It was a living fossil in its time.”

“It’s a really strange animal, and the weird twist in the jaw drove us crazy trying to figure it out. But nine jaws we’ve found have this twist, including the really well-preserved ones, so it’s not a deformation. It’s just the way this animal was.”

The findings of the study were published in the journal Proceedings of the Royal Society Bopens in a new window.

New species of “living fossil” had jaws unlike anything seen beforeg