The fossilised foot of a three-toed dinosaur that lived in Brazil 115 million years ago has been identified as belonging to a new species of bird forerunners.
The carnivore — dubbed 'Aratasaurus museunacionali' — was unearthed in 2008 from a layer of dark shale in the Pedra Branca mine in Ceará State by a local resident.
Experts believe that the dinosaur died young, but likely already weighed some 5.4 stones (34 kilograms) in life and would have stood more than 10 feet (3 metres) tall.
A. museunacionali was a medium-sized theropod — the group of bird-like dinosaurs characterised by their three-toed limbs and hollow bones.
The discovery of the new species may help scientists better understand the evolutionary history of this carnivorous dinosaur group.
'Within theropods, we discovered that Aratasaurus is part of a group called Coelurosauria,' paper author and palaeontologist Juliana Manso Sayão of the Federal University of Rio de Janeiro told Deutsche Welle.
These group, she added, 'includes both the Brazilian dinosaur found in the same region known as Santanaraptor, the famous Tyrannosaurus and velociraptors and even the birds that we know today.'
However, Dr Sayão and colleagues' analysis has suggested that Aratasaurus' lineage of dinosaurs may date back even further in time than the one that gave rise to T. rex.'Aratasaurus indicates that part of her rich history may lie in the northeast of Brazil and in South America,' Dr Sayão told Deutsche Welle.
'There are still many gaps to unveil in this evolutionary puzzle, but with this discovery, we have added another piece to understand it.
According to the researchers, the process of extracting the fossil from the fragile surrounding rock matrix was a complex process — and took 12 years in total.
The team performed microscopic analyses of tissue taken from small samples of the fossil bone, which helped them to form a 'visual construct' of the animal.
In 2018, the specimen luckily avoided disaster when another part of the museum in which it was stored at the time was destroyed by fire.
Researchers presented the newly-identified fossil A. museunacionali specimen to the National Museum of Rio de Janeiro on July 10.
The full findings of the study were published in the journal Scientific Reports.