Scientists of a Japanese team say a dinosaur fossil discovered in Uzbekistan is of a previously unknown species that topped the food web before tyrannosaurs.
The team from the University of Tsukuba reported its findings after examining the uncategorized fossil that was excavated in the Central Asian country more than 20 years ago.
The researchers say an upper jawbone of the fossil suggests that it belongs to a newer species of a large carnivorous dinosaur that lived about 90 million years ago in Late Cretaceous period.
They estimated that the dinosaur, named Ulughbegsaurus uzbekistanensis, was approximately 8 meters in length and weighed over 1,000 kilograms. It had a big mouth and sharp teeth.
The species is believed to have disappeared from the northern hemisphere before the Tyrannosaurus family became dominant as the apex predator about 84 million years ago. But the transition process remains totally unknown.
Assistant Professor Tanaka Kohei in the team said the findings will help understand the historical changes of dinosaurs at the top of the food web.