Mongolia s Dragon Prince dinosaur was forerunner of T rex

A newly identified mid-sized dinosaur from Mongolia dubbed the Dragon Prince has been identified as a pivotal forerunner of Tyrannosaurus rex in an illuminating discovery that has helped clarify the famous predators complicated family history.

Named Khankhuuluu mongoliensis (pronounced khan-KOO-loo mon-gol-ee-EN-sis),it lived roughly 86 million years ago during the Cretaceous Period and was an immediate precursor to the dinosaur lineage called tyrannosaurs, which included some of the largest meat-eating land animals in Earths history, among them T. rex. Khankhuuluu predated Tyrannosaurus by about 20 million years.

It was about 13 feet (4 meters) long, weighed about 1,600 pounds (750 kg),walked on two legs and had a lengthy snout with a mouthful of sharp teeth. More lightly built than T. rex, its body proportions indicate Khankhuuluu was fleet-footed, likely chasing down smaller prey such as bird-like dinosaurs called oviraptorosaurs and ornithomimosaurs. The largest-known T. rex specimen is 40-1/2 feet long (12.3 meters).

Khankhuuluu means Dragon Prince in the Mongolian language. Tyrannosaurus rex means tyrant king of the lizards.

In the name, we wanted to capture that Khankhuuluu was a small, early form that had not evolved into a king. It was still a prince, said paleontologist Darla Zelenitsky of the University of Calgary in Canada, co-author of the study published on Wednesday in the journal Nature.

Tyrannosaurs and all other meat-eating dinosaurs are part of a group called theropods. Tyrannosaurs appeared late in the age of dinosaurs, roaming Asia and North America.

Khankhuuluu shared many anatomical traits with tyrannosaurs but lacked certain defining characteristics, showing it was a predecessor and not a true member of the lineage.

Khankhuuluu was almost a tyrannosaur, but not quite. For example, the bone along the top of the snout and the bones around the eye are somewhat different from what we see in