UK Scientists Identify New Tiger-Sized Predator Dinosaur from 120-Million-Year-Old Fossil

A chunk of fossilized skull, tucked away in a museum drawer for nearly a century, has revealed a predator that stalked Early Cretaceous Europe 120 million years ago. Researchers at University College London identified the specimen as a new species of megaraptoran—a group of agile, two-legged carnivores that have remained largely mysterious to science because so few of their fossils survive. They named it Invictibellatrix amberina, meaning "unconquered female warrior," a deliberate nod to the group's eventual rise as apex predators across the southern supercontinent of Gondwana.

The fossil itself is modest: a piece of skull bone from the back of the head, discovered in 1924 by amateur paleontologist Reginald Walter Tooley at the foot of a cliff on the Isle of Wight's southwest coast. Tooley found more than a thousand specimens in his lifetime, and after his death, the Natural History Museum acquired his entire collection. This particular bone sat unexamined for decades until the UCL team undertook a CT scan, creating a three-dimensional model of the skull and the brain cavity within it. When researchers compared the fossil's features—an oval hole where the spinal cord entered the brain, an hourglass-shaped crest—against skulls from tyrannosaurs, spinosaurs, raptors, and other meat-eating dinosaurs, the pattern became clear. Computer algorithms analyzing how the skull's traits aligned with known species consistently placed it within the megaraptoran family.

Invictibellatrix was small by megaraptoran standards: three to four meters long, standing just over a meter and a half tall—roughly human height. It likely had feathers and curved claws measuring between ten and twenty centimeters. It hunted small dinosaurs, lizards, and mammals, occupying an ecological niche similar to a modern hyena. For context, the lead researcher noted that while this creature was not the apex predator of its time, it would have been far more dangerous to a human than a Tyrannosaurus rex. A person would have been perfectly sized prey—about a third of the megaraptoran's body weight—and would have been hunted. A T. rex, by contrast, would have ignored humans as too small to bother with.

The discovery fills a critical gap in paleontological understanding. Megaraptors are thought to have originated in Asia, then migrated through Europe before becoming dominant predators across Gondwana—the ancient southern supercontinent that included present-day Africa, South America, and Antarctica. Until now, that theory lacked European fossil evidence. No megaraptorans had ever been found on the continent. Invictibellatrix is the first proof that these predators actually inhabited Europe during the Early Cretaceous, confirming they could have traveled overland to reach Gondwana rather than island-hopping further south. Mathematical modeling of fossil distribution, evolutionary relationships, geography, and climate suggests megaraptors were globally widespread during the Early Cretaceous but likely went extinct in the northern landmass of Laurasia (modern-day Europe and Asia) tens of millions of years later, in the Late Cretaceous. By then, they had become massive apex predators in the south, with claws reaching thirty-five centimeters—creatures like Maip macrothorax from Argentina, which stretched nine to ten meters long and weighed as much as an elephant. Why they vanished from the north remains unexplained, though climate shifts, environmental change, or competition from other predators like tyrannosaurs may have played a role.

The research team chose the name Invictibellatrix deliberately. In their paper, they explained the choice was meant to "give hope and strength to all those who are bullied, discriminated, victimised, and oppressed that tomorrow will be theirs and not to give up in face of such odds." Amberina refers both to amber found in the rocks where the fossil was discovered and to the female name itself. The work was funded by the Palaeontographical Society, the Royal Society, and UK Research and Innovation.

The discovery underscores a broader truth about paleontology: major finds often emerge not from new excavations but from old collections. The Isle of Wight has yielded dinosaur fossils for over two centuries, yet it continues to surprise researchers with new species. Carnivorous dinosaurs, in particular, have been elusive finds on the island. The fact that Invictibellatrix sat in a drawer for nearly a hundred years before anyone recognized its significance raises an obvious question: what else remains overlooked in museum storage, waiting for someone to look closely enough to see what it is?