# Scientists have discovered a new species of dinosaur that they say “rewrites” the evolutionary history of tyrannosaurs. The two 86-million-year-old skeletons in the collection of a Mongolian museum is now the closest known ancestor of all tyrannosaurs, the group of predators that includes the iconic T Rex. It is named Khankhuuluu Mongoliensis, meaning Dragon Prince of Mongolia. Prince refers to it being an early, smaller tyrannosauroid that walked on two legs. Khankhuuluu would have weighed about 750 kilograms, with an adult T Rex at least eight times heavier.
New species of dinosaur rewrites T Rex family tree