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Adasaurus

Adasaurus is a genus of dromaeosaurid dinosaur that lived in Asia during the Late Cretaceous period. This large predator is known from two partial specimens discovered in Mongolia's Nemegt Formation. Adasaurus is distinguished by a notably reduced sickle claw on its second toe, a feature that sets it apart from many of its relatives.

Key Facts

  • Lived in Asia during the Late Cretaceous period.
  • Discovered in the Nemegt Formation of Mongolia.
  • Estimated length of 2.39–3.5 meters (7.8–11.5 ft).
  • Estimated weight of 36.4–87 kg (80–192 lb).
  • Characterized by a small and blunt sickle claw on its second toe.
  • Belongs to the dromaeosaurid family, closely related to birds.
Adasaurus
Scientific Name
Adasaurus mongoliensis
Common Name
Adasaurus
Physical Characteristics

Estimated length of 2.39–3.5 m, Estimated weight of 36.4–87 kg, Small and blunt sickle claw on the second toe, Recurved lacrimal bone, Expanded projection of the maxillary, Lower jaw with a prominent surangular foramen

Habitat
River channels, mudflats, and shallow lakes
Estimated Length M
3.5
Estimated Weight Kg
87
Dinosaur Group
Dromaeosaurid
Temporal Range
Late Campanian to Early-Middle Maastrichtian
Named By
Rinchen Barsbold
Year Named
1983
Related Species

Velociraptor, Austroraptor, Achillobator, Saurornitholestes, Balaur

Etymology
The genus name 'Adasaurus' combines the Mongolian word 'ada' (evil spirit) with the Greek word 'sauros' (lizard). The species name 'mongoliensis' refers to its discovery location in Mongolia.
Fossil Record Quality
Partial specimens
Geographic Distribution

Asia

About Adasaurus

Adasaurus is a genus of dromaeosaurid dinosaur that roamed Asia during the Late Cretaceous period. Known from partial fossil remains discovered in Mongolia's Nemegt Formation, this medium-sized predator provides insights into the diversity of sickle-clawed dinosaurs.

History of Discovery and Naming

The genus Adasaurus was formally named and described by Mongolian paleontologist Rinchen Barsbold in 1983. The name "Adasaurus" is a combination of the Mongolian word "ada" (evil spirit) and the Greek word "sauros" (lizard), translating to "evil lizard." The type species, Adasaurus mongoliensis, signifies its origin in Mongolia. The fossils were unearthed from the Nemegt Formation, a rich fossil-bearing site.

Physical Characteristics and Anatomy

Adasaurus was a dromaeosaurid of considerable size, with estimated lengths ranging from 2.39 to 3.5 meters (7.8 to 11.5 feet) and weights between 36.4 and 87 kilograms (80 to 192 pounds). A key distinguishing feature of Adasaurus is its unusually reduced sickle claw on the second toe, which was smaller and blunter than those found on many other dromaeosaurids. This morphology suggests a potentially different or less pronounced role for this characteristic predatory appendage compared to its relatives. Other notable anatomical features include a recurved lacrimal bone, expanded maxillary projections, and a prominent surangular foramen on the lower jaw.

Classification and Paleobiology

Adasaurus belongs to the Dromaeosauridae family, a group of theropod dinosaurs closely related to modern birds. While initially considered a dromaeosaurine, later analyses have placed Adasaurus within the Velociraptorinae subfamily, which includes more lightly-built dromaeosaurs. The function of its reduced sickle claw has been a subject of discussion, with some paleontologists suggesting it had a less specialized use than in other deinonychosaurs. The paleoenvironment of the Nemegt Formation suggests Adasaurus lived in a diverse ecosystem with river systems and abundant vegetation, sharing its habitat with various other dinosaurs.

Source: Wikipedia ↗

Frequently Asked Questions

What does the name Adasaurus mean?

The name Adasaurus is derived from the Mongolian word 'ada,' meaning 'evil spirit,' and the Greek word 'sauros,' meaning 'lizard.' Thus, Adasaurus translates to 'evil lizard.'

Where were Adasaurus fossils found?

Fossils of Adasaurus have been discovered in the Nemegt Formation, located in the Gobi Desert of Mongolia. The specific locality mentioned is Bügiin Tsav.

What was the estimated size of Adasaurus?

Adasaurus was a relatively large dromaeosaurid. The holotype specimen is estimated to have been about 2.39 meters (7.8 ft) long, while a larger paratype specimen suggests a length of up to 3.5 meters (11 ft).

What is distinctive about Adasaurus's sickle claw?

Unlike many other dromaeosaurids which possessed large and sharply developed sickle claws, Adasaurus had a rather small and blunt sickle claw on its second toe. This reduction suggests it may have had a less prominent role in predation compared to its relatives.

What kind of environment did Adasaurus live in?

Adasaurus inhabited the paleoenvironment of the Nemegt Formation, which featured stream and river channels, mudflats, and shallow lakes. This rich habitat offered abundant vegetation, supporting various herbivorous dinosaurs.

What other dinosaurs lived alongside Adasaurus?

During the Late Cretaceous, Adasaurus shared its environment with a diverse array of dinosaurs. These included ornithomimosaurs like Gallimimus, oviraptorosaurs such as Nemegtomaia and Gobiraptor, and large theropods like Tarbosaurus and Saurolophus.