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Therizinosaurus

Therizinosaurus is a genus of large therizinosaurid dinosaur from the Late Cretaceous of Mongolia, known especially for its enormous hand claws.

By Ethan Anderson| Reviewed by Olivia Bennett, Standards & Fact-Checking Lead| Updated July 26, 2026|2 min read| Fact-checked

Therizinosaurus is a genus of large therizinosaurid dinosaur from the Late Cretaceous of Mongolia, known especially for its enormous hand claws. It was a bipedal, likely herbivorous theropod and is represented by very incomplete fossil material. The single named species is Therizinosaurus cheloniformis.

Discovery and fossils

Therizinosaurus is known from incomplete remains, especially the distinctive hand claws, rather than from a complete skeleton. Its fossils come from the Nemegt Formation in Mongolia.

Classification

Therizinosaurus belongs to Therizinosauria, a group of theropod dinosaurs within Maniraptora. Although theropods are often carnivorous, therizinosaurs are widely understood to have been herbivorous.

Physical characteristics

Reconstructions depict Therizinosaurus as a large, bipedal dinosaur with a long neck, small head, and very long forelimbs. Its most notable feature was the huge claws on its three-fingered hands.

Palaeoecology

Therizinosaurus lived during the Late Cretaceous in what is now Mongolia. It shared its environment with other Nemegt Formation dinosaurs and is usually presented as a browsing plant-eater.

Key facts

  • Therizinosaurus is known for its enormous hand claws.
  • It is a herbivorous theropod from the Late Cretaceous of Mongolia.
  • Only one named species exists: Therizinosaurus cheloniformis.
  • Fossils are incomplete, with size estimates around 9–10 metres long.
  • It lived in the Nemegt Formation and is considered a plant-eater.

Frequently asked questions

What is Therizinosaurus?
Therizinosaurus is a genus of large therizinosaurid dinosaur known from the Late Cretaceous of Mongolia.
What does the name Therizinosaurus mean?
The name means “scythe lizard,” a reference to its long hand claws.
What did Therizinosaurus eat?
It is generally considered to have been herbivorous, although its exact feeding behaviour is not fully known.
Where was Therizinosaurus found?
Its fossils were found in the Nemegt Formation of Mongolia.
How big was Therizinosaurus?
Estimates vary, but it is often reconstructed at roughly 9–10 metres long.
Is Therizinosaurus a theropod?
Yes. It was a theropod, specifically a therizinosaurid theropod within Maniraptora.

References

  1. Natural History Museumhttps://www.nhm.ac.uk/discover/dino-directory/therizinosaurus.html
    Supports: Name meaning, Late Cretaceous age, plant-eating habit, bipedal posture, and large claws.
  2. Wikipediahttps://en.wikipedia.org/wiki/Therizinosaurus
    Supports: Single named species, Nemegt Formation occurrence, and broad size estimates.
  3. Encyclopaedia Britannicahttps://www.britannica.com/animal/therizinosaur
    Supports: Therizinosaur classification and general traits of the group, including long claws and herbivory.