It is one of thousands of ancient fossils that have disappeared from the country since American explorer Roy Chapman Andrews - supposedly the inspiration for the movie character Indiana Jones - discovered dinosaur eggs there nearly a century ago.
Paleontologists and smugglers alike have descended on the sands ever since.
Now the Mongolian government is mounting a campaign to reclaim the lost relics, hoping to bring home fossils long held in foreign museums and the curiosity cabinets of private collectors - such as Hollywood star Nicolas Cage - who pay hundreds of thousands of dollars for them on the open market.
The dinosaur repatriation drive began when the husband of the country's then culture, sport and tourism minister Oyungerel Tsedevdamba learned a New York auction house was to sell a rare, nearly complete Tarbosaur bataar specimen - a smaller, fiercer cousin of Tyrannosaurus rex.
Also Read
Palaeontologists confirmed that all known specimens of the fearsome reptile had come from Mongolia's Nemegt basin, raising the question of how it ended up in Manhattan.
Removing fossils from the country is illegal, but "nobody knew what to do exactly", Oyungerel told AFP. "Nobody had claimed dinosaurs from abroad before."
It is nearly impossible to prevent thefts from Mongolia's vast steppe, said Surenjav Munkhsaikhan, 31, who manages the national park where Chapman found the eggs.
She is the only full-time guardian of over 10,000 hectares of fossil-rich desert, working with police and her volunteer deputy Gelegrash to combat crimes ranging from illegal mining to the theft of rare plants.
She patrols the area on an old motorbike, but "really wants some drones", she said.
Disclaimer: No Business Standard Journalist was involved in creation of this content