Fossils found in Chile are from a strange-looking dog-sized dinosaur species that had a unique slashing tail weapon, scientists reported Wednesday.

Some dinosaurs had spiked tails they could use as stabbing weapons and others had tails with clubs. The new species, described in a study in has something never seen before on any animal: seven pairs of B次元官网网址渂ladesB次元官网网址� laid out sideways like a slicing weapon used by ancient Aztec warriors, said lead author Alex Vargas.

B次元官网网址淚tB次元官网网址檚 a really unusual weapon,B次元官网网址� said Vargas, a University of Chile paleontologist. B次元官网网址淏ooks on prehistoric animals for kids need to update and put this weird tail in there. B次元官网网址� It just looks crazy.B次元官网网址�

The plant-eating critter had a combination of traits from different species that initially sent paleontologists down the wrong path. The back end, including its tail weapon, seemed similar to a , so the researchers named it stegouros elengassen.

After Vargas and his team examined the pieces of skull and did five different DNA analyses, they concluded it was only distantly related to the stegosaurus. Instead, it was a rare southern hemisphere member of the tank-like family of dinosaurs. (Though the stegouros name stuck and can be easily confused with the more well-known stegosaurus.)

Vargas called it B次元官网网址渢he lost family branch of the ankylosaur.B次元官网网址�

The fossil is from about 72 million to 75 million years ago and appears to be an adult based on the way bones are fused, Vargas said. It was found with its front end flat on its belly and the back end angled down to a lower level, almost as if caught in quicksand, Vargas said.

From bird-like snout to tail tip, stegouros stretched about six feet (two meters) but would only come up to the thighs of humans, Vargas said.

The tail was probably for defense against large predators, which were also likely turned off by armor-like bones jutting out that made stegouros B次元官网网址渃hewy,B次元官网网址� Vargas said.

Not only is this B次元官网网址渁 really bizarre tail,B次元官网网址� but it is from far southern Chile, B次元官网网址渁 region that hasnB次元官网网址檛 yielded these types of animals before,B次元官网网址� said Macalester College biologist Kristi Curry Rogers, who wasnB次元官网网址檛 part of the study.

B次元官网网址淲eB次元官网网址檙e just scratching the surface when it comes to a comprehensive understanding of dinosaur diversity,B次元官网网址� Rogers said. B次元官网网址淪tegourus reminds us that if we look in the right places at the right times, there is so much more still to discover.B次元官网网址�

B次元官网网址擲eth Borenstein, The Associated Press