In 1924, an amateur palaeontologist found a fossil in the UK that remained unstudied for years. Now a century later, scientists say it's a new dinosaur species

Scientists have identified a new species of dinosaur from a fossil discovered on the Isle of Wight in the UK, the Natural History Museum has announced in a press release. The predator, estimated to have been the size of a large tiger, belonged to a group of dinosaurs called as megaraptorans that lived about 120 million years ago. As per a study published in the journal Royal Society Open Science, the discovery marks the first confirmed evidence of megaraptorans in Europe. The finding also provides new clues about how these dinosaurs spread across the world during the Early Cretaceous period.

Meet Invictibellatrix amberina

Named Invictibellatrix amberina, the dinosaur is believed to be as tall as a human measuring three to four metres in length and over 1.5 metres in height. Lead author Dr Cassius Morrison (UCL Earth Sciences) said it may have had feathers and curved claws measuring between 10 and 20 centimetres long. The said dinosaur, reserchers believe, would have eaten small dinosaurs, lizards and mammals – occupying a similar role in the food chain to the hyena today.

“It was not the apex predator of its time, but for humans this dinosaur would have been more dangerous than a T. rex. We would have been perfectly sized prey, about a third of their body weight. They definitely would have chased us. A T. rex would not have bothered, as we would have been too small," Morrison added.


According to Morrison, the dinosaur would have been large enough to pose a threat to humans. "It was not the apex predator of its time, but for humans this dinosaur would have been more dangerous than a T. rex. We would have been perfectly sized prey, about a third of their body weight. They definitely would have chased us. A T. rex would not have bothered, as we would have been too small."

What were megaraptorans?

Megaraptorans were agile, two-legged carnivorous dinosaurs closely related to tyrannosaurs, including Tyrannosaurus rex. Unlike tyrannosaurs, which relied heavily on their powerful jaws, megaraptorans had relatively slender skulls and large arms equipped with prominent, curved claws.

Although some members of the group eventually reached enormous sizes, Invictibellatrix amberina was among the smaller and earlier examples identified so far. Researchers believe the dinosaur hunted small dinosaurs, lizards and mammals, occupying a role in its ecosystem comparable to that of modern hyenas.

A fossil overlooked for nearly a century

The fossil wasn't a new discovery. Amateur palaeontologist Reginald Walter Tooley first found it at the foot of a cliff on the south-west coast of the Isle of Wight. The specimen was acquired by the Natural History Museum in 1924 but remained largely unstudied for decades until now. It was among more than 1,000 specimens collected by Tooley that entered the museum's collection after his death.

Dr Cassius Morrison is now hopeful of many new discoveries after this. “It is a real mystery that this fossil was overlooked for so long, sitting in a drawer for nearly 100 years. Lots of bones are found on the Isle of Wight – who knows what else is waiting to be discovered,” said Morrison.

How scientists identified the new species

To determine the fossil's identity, researchers conducted a CT scan and created a three-dimensional model of the skull fragment, along with a model of the interior of the skull, including the brain cavity.

They compared its features with those of tyrannosaurs, spinosaurs, other raptors and several other groups of two-legged carnivorous dinosaurs.

A distinctive combination of anatomical characteristics, including an oval opening where the spinal cord entered the brain and an hourglass-shaped crest, helped establish that the specimen represented a previously unknown species.

Computer algorithms that analysed the skull's characteristics alongside those of other dinosaurs repeatedly placed it within the megaraptoran group.

The team also used mathematical modelling to investigate how megaraptorans spread geographically over millions of years. The analysis incorporated known fossils, evolutionary relationships, geography and climate.

What the discovery reveals about dinosaur evolution

Megaraptorans are among the least understood groups of large carnivorous dinosaurs because relatively few fossils have been discovered. Scientists believe that the group originated in Asia before spreading through Europe and eventually reaching Gondwana, the southern landmass that included present-day Africa, South America and Antarctica.

However, the absence of confirmed European fossils had left a gap in the evidence supporting this migration route. The discovery of Invictibellatrix amberina provides the first evidence that megaraptorans lived in Europe, supporting the theory that they moved south towards Gondwana through the continent.

Co-author Charlie Scherer, a PhD student at UCL Earth Sciences, said the finding helped establish a possible route through which the dinosaurs reached Gondwana. “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.”

The researchers' modelling suggests megaraptorans were widely distributed across the world during the Early Cretaceous period. By the Late Cretaceous, tens of millions of years later, they may have disappeared from Laurasia, the northern landmass that included modern-day Europe.

During this later period, megaraptorans became apex predators in parts of Gondwana and evolved into much larger animals, with some species possessing claws measuring up to 35 centimetres.

The study did not establish why the group disappeared from northern regions. Changes in climate or habitats, as well as competition from other predators, including tyrannosaurs, may have contributed to their decline.

Why the dinosaur was given its name

The name Invictibellatrix means “unconquered female warrior”. The researchers chose it to recognise the group's later evolution into large apex predators. The species name amberina refers both to the amber found in the rocks where the fossil was discovered and to a female name.

In the paper, the researchers said the name Invictibellatrix was intended 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”.

The research received funding from the Palaeontographical Society, the Royal Society and UK Research and Innovation (UKRI).