New dog-sized dinosaur identified after fossil mix-up

  • The dog-sized dinosaur was previously misclassified by scientists
  • About 3 feet long, its tail made up about half of its length
  • It roamed the planet at the same time as the stegosaurus

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(NewsNation) — A new species of dinosaur the size of a Labrador retriever has been identified after scientists managed to untangle a fossil mix-up.

Incomplete fossil remains of the newly named enigmacursor mollyborthwickae were initially discovered in modern-day Colorado in 2021-22 but were misclassified by scientists as being the remains of a nanosaurus.

In a newly published report, scientists behind the discovery note that the small herbivore was about 3 feet long, with its tail making up about half of its length.

According to the museum, the name enigmacursor roughly translates to “puzzle runner” in Latin. Despite its small stature, this two-legged dinosaur had long legs, which allowed it to quickly move away from predators.

“We can speculate that Enigmacursor probably wasn’t that old, as it doesn’t seem to have many of its neural arches fused in place. However, the way the fossil was prepared before it was acquired by the Natural History Museum has obscured some of these details, so we can’t be certain,” Paul Barrett, co-lead author, said.

The remains, which date back to roughly 150 million years ago, are now on display at the Natural History Museum in London, marking the museum’s first new dinosaur on display since 2014. Unearthed from the Morrison Formation of the Western United States, the dinosaur is said to have roamed the same region as dinosaurs like the stegosaurus and diplodocus.

“While the Morrison Formation has been well-known for a long time, most of the focus has been on searching for the biggest and most impressive dinosaurs,” professor Susannah Maidment, co-lead author of the report, told the museum. “Engimacusor shows that there’s still plenty to discover in even this well-studied region and highlights just how important it is to not take historic assumptions about dinosaurs at face value.”

Science News

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