Newly discovered dinosaur in Mongolia had only two claws

A team of palaeontologists has discovered a rare dinosaur species in Mongolia’s Gobi Desert, naming it Duonychus tsogtbaatari. Unlike its therizinosaur relatives, which typically had three claws on each hand, this species had only two.

Weighing an estimated 260kg, Duonychus tsogtbaatari lived during the Late Cretaceous period, approximately 100.5 to 66 million years ago. The discovery was made in the Bayanshiree Formation, a fossil-rich site that has previously yielded many important dinosaur specimens.

Scientists believe the dinosaur’s two elongated, curved claws may have been used for grasping vegetation, digging, or self-defense. While therizinosaurs were closely related to carnivorous theropods like Tyrannosaurus rex, they were herbivores or omnivores, evolving long claws to aid in foraging rather than hunting.

Dr. Darla Zelenitsky, a palaeontologist at the University of Calgary, noted that Duonychus tsogtbaatari evolved its two-fingered hands independently from tyrannosaurs. “It’s a fascinating example of convergent evolution,” she explained. “Unlike T. rex, which had reduced arms and fingers, Duonychus may have adapted its claws for a specific ecological niche.”

One of the most significant aspects of the discovery is the presence of a preserved keratinous sheath—the first known example in a therizinosaur. Similar to the outer layer of human fingernails, this sheath would have reinforced the claws, potentially improving their function.

The Gobi Desert has long been a hotspot for fossil discoveries, and this latest find adds to scientists’ understanding of therizinosaur diversity. Researchers continue to analyze the remains, hoping to uncover more details about how Duonychus lived and interacted with its environment.

This discovery highlights the complexity of dinosaur evolution and provides new insights into the adaptations that helped different species thrive in prehistoric ecosystems.