This Dinosaur Found in Chile Had a Battle Ax for a Tail

While ankylosaurs are already known for their armor and club tails, this specimen from South America had a unique way of fighting predators.

It’s not every day you find a dinosaur that defended itself from predators with a completely unique weapon.

In a study published Wednesday in Nature, Chilean researchers announced the discovery of a new species of ankylosaur, a family of dinosaurs known for their heavy armor, from subantarctic Chile. The animal, which they named Stegouros elengassen, offers new clues about where these tank-like dinosaurs came from — and features a bizarre, bony tail shaped like a club that was wielded by Aztec warriors.

“It’s lacking most of the traits we’d expect from an ankylosaur and has a completely different tail weapon which shows there’s something very idiosyncratic happening here in South America,” said Alexander Vargas, a professor at the University of Chile and a co-author on the study.