The tail somewhat resembles a macuahuitl; a feared ‘sword’ that was used as a weapon by the Aztecs, among others.

Researchers have unearthed the remains of a very peculiar dinosaur in Chilean Patagonia. It is a species that shows both Ankylosaurus and Stegosaurus characteristics and roamed the earth about 74 million years ago. What is particularly striking about the dinosaur is its bizarre tail, which resembles a feared Aztec weapon.

Discovery

Several years ago, researchers managed to excavate a heavy rock containing some visible fossils with great difficulty. The boulder was discovered in a fairly inhospitable area at the southernmost tip of Chile. The rock was transferred to a research facility, where it was thoroughly studied. And here the researchers stumbled upon an astonishing discovery. The team found a particularly well-preserved dinosaur skeleton. Virtually all of the bones were intact, including those of his peculiar tail.

Tail

The researchers decided to inspect the tail in particular. For this one “differs greatly from any known tail of any dinosaur hitherto unearthed.” In the back half, the team found seven large, bony plates (osteoderms), which together seem to form a kind of frond. Although the researchers also think that the flattened tail resembles a macuahuitl; a feared ‘sword’ that was used as a weapon by the Aztecs, among others.

The bizarre tail that somewhat resembles a macuahuitl. Image: University of Chile

Stegouros elengases

Thanks in particular to this ‘deadly’ tail, the researchers knew that they had an as-yet-unknown dinosaur in front of them. The researchers have identified the species ‘Stegouros elengases’ called. ‘stegouros’ means something like ‘covered tail’, while ‘elengas’ refers to a mythical armored monster in the tradition of the local native Aonikenk; nomadic hunter-gatherers who were part of the original population of Chilean Patagonia.

Characteristics

Because the fossil has withstood the test of time extremely well, the research team was also able to uncover interesting features. They state that the dinosaur must have been about two meters long. Moreover, it turns out Stegouros elengases to have inherited both Ankylosaurs and Stegosaurs traits; it seems that it was a unique, hybrid strain. The researchers suspect that Stegouros elengases was a kind of ‘transitional Ankylosaurus’; an evolutionary link between Ankylosaurs and other, older lineages of armored dinosaurs.

More about Ankylosaurus and Stegosaurus
Stegosaurs are considered hulking herbivores and are probably among the most recognizable dinosaurs to ever roam the Earth. This is mainly due to their famous vertical back plates and the pointy, dangerous whip tail. Ankylosaurs are known for their broad, bone-plate armored backs. He defended himself with the special mace that sat on the tip of his tail. Stegouros elengassen differs greatly from these species with its tail.

The researchers emphasize that we are just beginning to unlock the history of dinosaurs that once meandered through the Chilean landscape. “In 2011, the first species was described; a long-necked herbivore called Atacamatitan chilensis,” said researcher David Rubilar. “Now, ten years later, we describe a fourth species. This tells us how little we actually know about this part of the world. At the same time, this also indicates the enormous potential of this country for paleontological research. Further exploration of southern Chile and Antarctica is therefore likely to lead to new and spectacular discoveries in the future.”