A dinosaur fossil that sat in a museum collection for nearly 100 years has turned out to belong to a species scientists never knew existed.
The fossil, discovered on England’s Isle of Wight in 1924, was recently identified as a new species of predatory dinosaur named Invictibellatrix amberina, according to research published in the journal Royal Society Open Science.
“It’s a real mystery that this fossil was overlooked for so long,” paleontologist Cassius Morrison of University College London told The Independent.
The fossil had been part of London’s Natural History Museum collection for decades, but its significance remained unrecognized until researchers decided to take another look.
Using CT scans, scientists examined the fossilized skull bone and created three-dimensional models to compare it with the remains of other meat-eating dinosaurs.
They discovered an unusual combination of features, including a distinctive bony ridge and an oval-shaped opening where the spinal cord would have connected to the brain.
Those differences helped researchers determine that the fossil belonged to a previously unknown member of the megaraptoran group, according to Swiss news outlet Blue News.
The discovery is particularly significant because it provides the first definitive evidence that these dinosaurs once lived in Europe.
And while the newly identified predator was related to other meat-eating dinosaurs, including the group that gave rise to Tyrannosaurus rex, it looked quite different from the famous giant.
Researchers estimate that Invictibellatrix amberina measured approximately 10 to 13 feet long and stood around 5 feet tall. It may also have had feathers and large, curved claws measuring roughly 4 to 8 inches long.
Unlike T. rex, which is known for its enormous jaws and relatively small arms, megaraptorans are thought to have relied more heavily on their powerful arms and claws to catch prey.
Morrison even suggested that a dinosaur of this size might have posed a greater threat to humans than an adult T. rex, had people existed at the same time.
“We would have been perfectly sized prey, about a third of their body weight. They definitely would have chased us,” he told The Independent. “A T rex would not have bothered, as we would have been too small.”
However, researchers have only identified part of the animal’s skull, meaning much of its appearance and behavior has been reconstructed using evidence from related dinosaurs.
Beyond identifying a new species, the fossil is also helping scientists better understand how megaraptorans spread around the world millions of years ago.
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Researchers believe the group moved through Eurasia before eventually reaching southern landmasses, where some evolved into enormous predators.
“This new species is the first proof we have that megaraptorans were also present in Europe and that they reached Gondwana this way rather than island-hopping further south,” study co-author Charlie Scherer told The Independent.