New armored species discovered in Chile had bizarre cocked tail
About 2 m in size, the small armored dinosaur called the ankylosaurus dates back to the Late Cretaceous Period, around 71.7 million to 74.9 million years ago.
Its largely complete fossilized skeleton was found in the province of Magallanes in Patagonia, the southernmost region of Chile.
The dinosaur, named Stegouros elengassen, had developed a large tail weapon unlike those seen in other armored dinosaurs such as the twin spikes of Stegosaurus and the club-shaped tail of Ankylosaurus.
The dinosaur’s tail had seven pairs of flattened bone deposits fused into a sling-like structure.
“The tail is extremely strange, because it is short for a dinosaur and the posterior half is enclosed in dermal bones (bones that grow in the skin) forming a unique weapon (tail),” said Sergio Soto Acuña, senior author of the study. and a doctoral student at the Universidad de Chile, by e-mail.
He said it looked like the tail of a rattlesnake or spiny tailed lizard. But unlike these creatures, the dinosaur had real bones under the scales.
The most similar feature is said to be the tail of a giant armadillo, but they are also extinct, he added.
Stegouros means “covered tail” in Greek and “elenggassen” comes from Aonikenk, the language of the first inhabitants of Patagonia, and refers to a mythological armored beast. The fossil was found in 2018.
The study noted that very few ankylosaurs had been found in southern Gondwana, the lower part of the former Pangea supercontinent.
“Unlike the ankylosaurs of the northern hemisphere, our new dinosaur has light armor, slender legs and a smaller size,” he said.
Fossilized plants discovered in the same area indicate that the climate was warmer when this dinosaur inhabited the place – very different from the current cold climate that prevails in Patagonia.