File photo for representational purposes only.
Paris: Misidentified bones that languished in the drawers of a Mongolian institute for 50 years belong to a new species of tyrannosaur that rewrites the family history of the mighty T-Rex, scientists said Wednesday.
This slender ancestor of the massive Tyrannosaurus Rex was around four metres (13 feet) long and weighed three quarters of a tonne, according to a new study in the journal Nature.
"It would have been the size of a very large horse," study co-author Darla Zelenitsky of Canada's University of Calgary told AFP.
The fossils were first dug up in southeastern Mongolia in the early 1970s but at the time were identified as belonging to a different tyrannosaur, Alectrosaurus.
For half a century, the fossils sat in the drawers at the Institute of Paleontology of the Mongolian Academy of Sciences in the capital Ulaanbaatar.
Then PhD student Jared Voris, who was on a trip to Mongolia, started looking through the drawers and noticed something was wrong, Zelenitsky said.
It turned out the fossils were well-preserved, partial skeletons of two different individuals of a completely new species.
"It is quite possible that discoveries like this are sitting in other museums that just have not been recognised," Zelenitsky added.
