The narrow-nosed beast was slightly smaller and more slender than T. rex, but was still a top predator, researchers say. It roamed the Earth more than 66 million years ago during the Late Cretaceous period, just before the space-rock impact that is believed to have wiped out the dinosaurs.
"People have a picture of tyrannosaurus apex predators -- the biggest, baddest, meanest dinosaurs," said study researcher Steve Brusatte, a paleontologist at the University of Edinburgh, in Scotland.
The new dinosaur fits that image in some ways, but not quite as closely as T. rex does. Although big and at the top of the food chain, the long-nosed dino wouldn't have been able to "crunch through bone" like T. rex, Brusatte told Live Science. [Image Gallery: The Life of T. Rex]
Long-nosed dinos
Researchers previously found the complete skull and parts of the neck, back, hind limbs and tail of the new dinosaur, Qianzhousaurus sinensis, at a construction site in the Nanxiong Formation in southeastern China. Brusatte and his colleagues then analyzed the fossils, which are now housed at the Ganzhou Museum in Ganzhou City, China.
The new specimen had a long snout with many teeth, and horns on its nose. The creature probably weighed a little less than a ton and was probably 25 to 30 feet (7.5 to 9 meters) long, compared with a full-grown T. rex, which weighed about 5 tons and was about 40 feet (12 m) long, the researchers said.
"It really is a beautiful specimen," Brusatte said.
Previously, scientists had discovered two other long-snouted tyrannosaur fossils, from the Alioramus genus, in Mongolia, but researchers had debated whether these represented a new class of dinosaur or merely juveniles of a known tyrannosaur.
'Pinocchio Rex,' which is twice the size of these other dinosaurs and was close to adulthood when it perished, offers "pretty clear evidence" that these long-snouted fossils represent a new group of tyrannosaurs, Brusatte said. The fact that specimens have been found from Mongolia to southeastern China suggests the animals were fairly widespread, he added.
Top predator?
The long-muzzled beast likely lived alongside other tyrannosaurs, such as Tarbosaurus, the Asian equivalent of T. rex. But "Pinnochio Rex" didn't compete with those species directly, because it probably hunted other, smaller prey, researchers said.
"It's a cool specimen," said Thomas Holtz, a vertebrate paleontologist at the University of Maryland, in College Park, who was not involved in the study but was a reviewer on the paper. "It helps show that tyrannosaurs were pretty diverse and weren't all the big bruisers that Tyrannosaurus or Tarbosaurus were."
Brusatte and colleagues said Pinocchio Rex was a "top predator" in its ecosystem, likely feeding on small, feathered dinosaurs or lizards.
David Burnham, a paleontologist at the University of Kansas, in Lawrence, said the description of the specimen's long snout and tiny front teeth more resembles a fish-eating creature such as a crocodile than a top predator.
Though that idea is interesting, Brusatte said, there are many anatomical differences between long-snouted, fish-eating crocodiles and the long-snouted tyrannosaurs.
Mark Norell, a paleontologist at the American Museum of Natural History, in New York, agreed with Brusatte's interpretation. "I think [the new specimen is] fairly closely related to Alioramus," the previously discovered long-snouted dinosaurs, Norell told Live Science.
The study researchers say they expect more specimens from this species and others will be discovered in Asia in the coming years.
"People are finding new species of dinosaur about once a week," Brusatte said. "China is the frontier in paleontology now."
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