
Palaeontologists have unearthed a previously unknown species of dinosaur in Mongolia’s Gobi Desert, named Duonychus tsogtbaatari, BBC reported.
This newly identified species is unique among therizinosaurs, a group of bipedal dinosaurs that typically possessed three claws on each hand.
Unlike its three-clawed relatives, Duonychus tsogtbaatari had only two large, curved claws, which researchers believe were highly specialised for grasping vegetation.
The dinosaur, estimated to have weighed around 260kg, lived during the Late Cretaceous period, approximately 100.5 to 66 million years ago.
The discovery was made in the Bayanshiree formation, a rich fossil site in the Gobi Desert, which UNESCO describes as one of the world’s most significant dinosaur fossil reservoirs. The Gobi region has yielded numerous specimens from the late Cretaceous, a period that saw the last major phase of dinosaur evolution.
Dr Darla Zelenitsky, a study co-author and associate professor at the University of Calgary, described therizinosaurs as “awkward-looking” creatures, pointing to the massive claws of their famous relative, Therizinosaurus, which was featured in the film Jurassic World Dominion.
One of the most remarkable aspects of this discovery is that the Duonychus tsogtbaatari specimen preserves the first known keratinous sheath of a therizinosaur claw.
This sheath, similar to the outer covering of human fingernails, would have enhanced the claw’s strength and utility, potentially aiding in defence, movement, or even foraging.
The significance of this two-fingered adaptation remains a topic of ongoing study. While two-fingered theropods such as Tyrannosaurus rex are well known, Duonychus tsogtbaatari evolved this trait independently, making it a unique case in dinosaur evolution.
Researchers speculate that the reduced number of claws may have been an evolutionary response to specialised feeding habits or environmental factors.
This discovery provides new insights into the diversity of therizinosaurs and adds to our understanding of dinosaur evolution during the late Cretaceous.