The ferocious carnivore, nine metres long with a distinctive horny snout, was a cousin of Tyrannosaurus rex. Its skeleton was dug up in a Chinese construction site and identified by scientists at Edinburgh University, UK.
The 66-million-year-old predator, officially named Qianzhousaurus sinensis, is described in Nature Communications. "Pinocchio rex" looked very different to other tyrannosaurs. "It had the familiar toothy grin of T. rex, but its snout was long and slender, with a row of horns on top," said Edinburgh's Dr Steve Brusatte.
"It might have looked a little comical, but it would have been as deadly as any other tyrannosaur, and maybe even a little faster and stealthier.
"We thought it needed a nickname, and the long snout made us think of Pinocchio's long nose."
Researchers now think several different tyrannosaurs lived and hunted alongside each other in Asia during the late Cretaceous Period, the last days of the dinosaurs.
The enormous Tarbosaurus (up to 13m) had deep and powerful jaws likeT. rex - strong enough to crush the bones of giant herbivores. The thinner teeth and lighter skeleton of Qianzhousaurus suggest it hunted smaller creatures, such as lizards and feathered dinosaurs. But at nine metres tall and weighing almost a tonne, it was still a gigantic carnivore.
The discovery of "Pinocchio" settles an argument over a series of strange new fossil finds. In recent years, two tyrannosaurs with unusually prominent proboscises were dug up in Mongolia, and named Alioramus. The horny-snouted predators appeared to come from an entirely new branch of the tyrannosaur family.