Erlikosaurus

Family

Theropod

Era

Late Cretaceous 90 million years ago

Where he lived?

Asia (Mongolia)

Weight

300 kg

Height

4 m

Length

2,5 m

Despite its fearsome appearance, the Erlikosaurus wasn’t a predator. This unusual theropod from the Late Cretaceous has captivated paleontologists and dino enthusiasts alike for its blend of strange features: a body likely covered in feathers, huge curved claws, a toothless beak… and a plant-based diet! So how does this “lizard of Erlik” fit into the dinosaur family tree?

A rule-breaking theropod

The Erlikosaurus belonged to the therizinosaurs, a family of dinosaurs so peculiar that they puzzled scientists for decades. Unlike classic theropods like the T. rex or the Velociraptor, this group evolved herbivore-like traits: long necks, beaked snouts, and a backward-pointing pubic bone (similar to ornithischians), suggesting a parallel evolution toward a vegetarian lifestyle.

The name Erlikosaurus andrewsi was proposed in 1980 by Barsbold, inspired by the demon Erlik, ruler of the underworld in Mongolian mythology. Ironically, this “demon” was more of a leaf picker than a fierce hunter.

Size, weight, and appearance

Although not one of the largest, the Erlikosaurus had an imposing appearance. Below are its estimated measurements:

Trait	Estimated Value
Total length	3.4 meters
Approx. height	1.6 m (at the hips)
Estimated weight	150–250 kg
Diet	Herbivore
Habitat	Mongolia (Bayanshiree Formation)

It had a relatively light frame, a long flexible neck, and a narrow skull with a toothless beak—perfect for munching soft vegetation. Its three large curved claws weren’t for hunting, but likely for pulling down branches, defense, or digging.

Did it have feathers?

Though no feather impressions have been found with the Erlikosaurus itself, it’s very likely that it was feathered. This theory is based on close relatives like the Beipiaosaurus, which did have filamentous feathers. Feathers may have helped regulate temperature in Mongolia’s changing climate.

Intelligence and senses

A CT scan of its fossilized skull revealed that the Erlikosaurus had a good sense of balance, hearing, and smell. Even though it was a herbivore, the Erlikosaurus retained sharp senses, likely inherited from carnivorous ancestors.

Diet and behavior

Thanks to its beak and U-shaped jaw, the Erlikosaurus is believed to have been a selective browser, eating leaves, fruit, and soft plants. Some scientists also suggest it used its claws to pull down branches or dig for roots.

It may have lived alone or in small groups, relying on intimidation rather than aggression. Its claws could have also played a role in mating rituals or social displays.