The discovery of a new species of dinosaur armed with a bladed tail similar to an Aztec war club means books on paleontology will have to be rewritten, experts said.
he two-metre-long dinosaur was a herbivore, but its tail, which was equipped with seven pairs of bony blades, meant it was more than capable of defending itself by slashing its predators.
Called Stegouros elengassen, it lived in Patagonia, part of what is now Chile, between 71 and 75 million years ago.
Its remains were found three years ago, but scientists have just published their findings in the journal Nature.
They initially thought they were dealing with a known species of dinosaur until they examined its tail, which they discovered was unlike any other dinosaur.
“It’s a really unusual weapon,’’ said Alex Vargas, a paleontologist at the University of Chile and lead author on the study.
“Books on prehistoric animals for kids need to update and put this weird tail in there. It just looks crazy.” The armoured tail would have resembled an ancient Aztec fighting club called a macuahuitl, which was embedded with obsidian blades.
Scientists said the discovery showed there was still much to learn about the diversity of the dinosaur world.
The seven pairs of blades, or osteoderms, were aligned on either side of the tail.
“We don’t know why the tail evolved. We do know that within armoured dinosaur groups there seems to be a tendency to independently develop different osteoderm-based defence mechanisms,” said Sergio Soto, another member of the team.
Despite its name, the new species is only distantly related to the more familiar stegosaurus.
Instead, stegouros is considered to be “the lost family branch of the ankylosaur” – a type of dinosaur known for its tank-like appearance, thick armour and club tail.
Weighing in at around 150kgs (24 stones), it lived in the late Cretaceous period. (© Telegraph Media Group Ltd 2021)
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