About 100 million years ago, a previously unknown armored dinosaur wielding a clubbed tail lumbered through the Canadian Rockies. The species resembled the well-known ankylosaurus (Nodosaurid ankylosaurs) — but with two major differences.
The first-ever identified footprints of this species sported only three toes (putting it into the ankylosaurid ankylosaurs category), instead of four (belonging to Tetrapodosaurus borealis). Also, the more known ankylosaurus swung its flexible tail to wield its club. The three-toes version’s tail was rigid and brandished more like a sledgehammer.
The tracks, found in both Alberta and British Columbia (BC), represent the first known example of ankylosaurid ankylosaur footprints anywhere in the world, the paleontologists who located them reported in the Journal of Vertebrate Paleontology.
A New Dinosaur Discovery
Victoria Arbour, the curator of paleontology at the Royal British Columbia Museum (RBCM) estimated that the new species maxed out at about 20 feet long, was protected by an armored spiky shell, and protected itself with a stiff, rather than flexible tail club.
“Ankylosaurs are my favorite group of dinosaurs to work on, so being able to identify new examples of these dinosaurs in British Columbia is really exciting for me,” Arbour said in a press release.
The team dubbed the new species of this ankylosaurid ankylosaur Ruopodosaurus clava — meaning “the tumbled-down lizard with a club/mace.” The first part of the name refers to the mountainous region where it was found, while the second half describes its distinctive tail.
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Co-existing Ankylosaurs
Charles Helm, scientific advisor at the Tumbler Ridge Museum, had noted the three-toed ankylosaur trackways around Tumbler Ridge, BC, for several years and invited Arbour to help identify and interpret them in 2023. A team of other scientists contributed to the analysis.
They date the tracks to the middle of the Cretaceous period, about 100 million years to 94 million years ago. Some paleontologists had speculated that, since no ankylosaurids bones had been found from that period in North America, the species had disappeared by then. The footprints contradict that narrative. The newly identified footprints also show that both types of ankylosaurs co-existed — and are giving this mountainous part of Canada a paleontological claim to fame.
“Ever since two young boys discovered an ankylosaur trackway close to Tumbler Ridge in the year 2000, ankylosaurs and Tumbler Ridge have been synonymous,” Helm said in a press release. “It is really exciting to now know through this research that there are two types of ankylosaurs that called this region home, and that Ruopodosaurus has only been identified in this part of Canada.”
Read More: Tail Clubs Weren't Just for Ankylosaurs – Some Sauropods Had Them, Too
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Journal of Vertebrate Paleontology. A new thyreophoran ichnotaxon from British Columbia, Canada confirms the presence of ankylosaurid dinosaurs in the mid Cretaceous of North America
Before joining Discover Magazine, Paul Smaglik spent over 20 years as a science journalist, specializing in U.S. life science policy and global scientific career issues. He began his career in newspapers, but switched to scientific magazines. His work has appeared in publications including Science News, Science, Nature, and Scientific American.
