The world’s oldest meat-eating dinosaur has been unearthed in southern Brazil.
Named Gnathovorax cabreirai, it lived 230 million years ago when South America was still part of the supercontinent called Pangea.
The skeleton is virtually intact – including razor-sharp teeth and claws that would have made it a ferocious ‘killing machine’. Its name means “ravenous jaws!”
Scientists were even able to reconstruct its brain – showing it had good eyesight and co-ordination.
This would have made it an ‘apex predator’ at the top of the food chain, said co-author Dr Rodrigo Muller.
The remarkable discovery sheds light on the evolution of T Rex.
Gnathovorax was about ten feet in length and weighed up to half a ton. It’s the first known carnivorous dinosaur – beating the previous record by more than 30 million years.
Mesozoic Era
Dinosaurs ruled the Earth for most of Mesozoic Era – between about 250 to 65 million years ago.
Most of the ‘super predators’ like Tyrannosaurus rex and Allosaurus lived tens of millions of years later during the Jurassic and Cretaceous.
Dr Muller, a biologist at the Federal University of Santa Maria, Brazil, said: “The oldest predatory dinosaurs – that lived during the Triassic around 230 million years before the present – are, however, still rare findings.
“Gnathovorax cabreirai is represented by an almost complete skeleton excavated in southern Brazil.
“The beast measured about three meters in length and is one of the oldest dinosaurs in the world.
“Moreover, it was one of the largest carnivores of its area 230 million years ago – much before its larger cousins from Jurassic and Cretaceous.”
The only other known dinosaurs that date back this far were less than twice the size – barely reaching five feet in length.
These include the plant-eating sauropod Buriolestes schultz found at a nearby fossil site three years ago.
Gave rise to T Rex
Gnathovorax was one of the original theropods that gave rise to T Rex.
Dr Muller said: “The outstanding skeleton possesses sharp teeth and claws, which may have been used by Gnathovorax to capture its prey.
“Additionally, the exquisitely preserved skeleton allowed us to reconstruct the shape of the brain of the animal – employing CT-scans.”
The computed tomography (CT) x-rays enabled his team to examine the skull’s interior – shedding light on Gnathovorax’s faculties.
Dr Muller said: “The effort revealed features shared with other predators, including well-developed areas related to visual coordination and balance.
“This combination of assets indicate that the new dinosaur was an
active predator of its time.
“Indeed, the name of the animal alludes to that – ‘Gnathovorax’ meaning ‘ravenous jaws’.”
Dr Muller said ‘cabreirai’ honours palaeontologist Dr Sergio Furtado Cabreira who made the discovery while excavating near the city of Santa Maria in the state of Rio Grande do Sul.
Gnathovorax, described in PeerJ, was a member of the first hunting dinosaurs called herrerasaurs.
They roamed Earth from around 233 million years ago – dying out about 30 million years later.
Dr Muller said: “The analysis places the new dinosaur closely related to Herrerasauridae, a group of predatory dinosaurs known from Argentina and Brazil.
“The new skeleton is however, the most complete single individual ever discovered for the group.”
The only other herrerasaur in Brazil was Staurikosaurus pricei represented by an incomplete skeleton recovered back in 1936 – more than eight decades ago.
Lead author Dr Cristian Pereira Pacheco, also of the Federal University of Santa Maria, said: “Although much information has been already gathered about the largest predatory dinosaurs from the Jurassic and Cretaceous Periods, their early evolutionary history is still poorly understood, given the scarcity of fossils.
“Here, we describe Gnathovorax cabreirai, a new herrerasaurid based on an exquisite specimen found in southern Brazil.
“Given its superb state of preservation and completeness, the new specimen sheds light into poorly understood aspects of the herrerasaurid anatomy – including soft tissues.”