Adasaurus
"evil spirit lizard"
- Lived
- 72 to 66 million years ago, Late Cretaceous
- Diet
- Carnivore
- Group
- Theropods, Dromaeosauridae
- Found in
- Mongolia
- Named by
- Barsbold 1977
Where its fossils were found
The evidence
Today
70 million years ago
Habitat
Rivers, floodplains and forests in Late Cretaceous Mongolia. The same rocks preserve Tarbosaurus, Deinocheirus and Saurolophus.
Field notes
About Adasaurus
What it was like
Adasaurus was a dromaeosaur, a feathered hunter related to Velociraptor. It was a bit larger than Velociraptor. Its sickle claw on each foot was smaller than in most of its relatives, which is unusual for the group.
Its world
It lived about 72 to 66 million years ago, in the Late Cretaceous, in what is now Mongolia. The Nemegt Formation was a land of rivers and forests, shared with the tyrannosaur Tarbosaurus, the giant clawed Therizinosaurus, the hump-backed Deinocheirus, the ostrich-like Gallimimus and the duckbill Saurolophus.
How it was found
Barsbold named Adasaurus in 1977. Its name comes from an evil spirit in Mongolian folklore. Only one find is known in detail.
Field gallery
More views of Adasaurus
Scenes reconstructed from the available fossil evidence.
1 of 3
Lived alongside
Found in the same rock formations
A rock formation can hold fossils laid down millions of years apart, so not every animal here met Adasaurus.
The evidence
The science behind Adasaurus
Which parts of the picture come from its own bones, and which come from its relatives.
From its own fossils
- Parts of the back of the skull, jaws, pelvis and body are preserved.
- The raised claw on the inner toe was unusually small for a dromaeosaur.
Borrowed from relatives
- The missing front of the head is restored using the long, low skull of Velociraptor as a comparison.
- Feather attachment bumps in a close relative support feathered arms and a feathered body for Adasaurus.
- Inward-facing palms and a long balancing tail follow other dromaeosaurs.
Still unknown
- The shape of the front of its skull.
- Its feather colors and the exact arrangement of its plumage.
- How it used its reduced foot claw.
Often drawn wrong
- A huge sickle claw copies other raptors; Adasaurus had a much smaller one.
- Its palms should face inward rather than down.
Discovery timeline
- 1977Named itBarsbold
- 2007Close relativeTurner, Makovicky & Norell
- 2012Full descriptionTurner, Makovicky & Norell
Key papers
The research behind what we know of Adasaurus
Named it
Introduced Adasaurus as a new meat-eating dinosaur from Mongolia.
O evolutsiy chishcheich dinosavrov [On the evolution of carnivorous dinosaurs]. Trudy - Sovmestnaya Sovetsko-Mongol'skaya Paleontologicheskaya Ekspeditsiya 4: 48-56
No link available
Close relative
Reported feather attachment bumps on a raptor's forearm, supporting feathered arms in relatives such as Adasaurus.
Feather quill knobs in the dinosaur Velociraptor. Science 317: 1721
Read the paper : Feather quill knobs in the dinosaur Velociraptor (opens in a new tab)Full description
Restudied Adasaurus, confirmed its reduced foot claw and rejected the idea that its unusual bones were diseased.
A Review of Dromaeosaurid Systematics and Paravian Phylogeny. Bulletin of the American Museum of Natural History 371: 1-206
Read the paper : A Review of Dromaeosaurid Systematics and Paravian Phylogeny (opens in a new tab)
Close relatives
Other members of Dromaeosauridae
Sources: Wikidata