They're called Mononykus. They can't be more than about six feet long and they feed mainly on insects.
— Allen, about Mononykus

Mononykus (name meaning "One Claw") is a genus of Alvarezsauridae theropod dinosaur that originated during the Late Cretaceous period in what is now Mongolia. Measuring no more than 2 meters long, this was a small, feathered, omnivorous dinosaur with long, skinny legs and one claw on each hand.

In the episode "The Giant Claw", a number of seven Mononykus were brought to the park from Late Cretaceous Mongolia, 80 million years ago. They reside in a forset/savannah-like environment.


Era & DiscoveryEdit

Mononykus lived in Mongolia during the Late Cretaceous period, from 80-65 million years ago, alongside dinosaurs like Saurolophus, Protoceratops, and Therizinosaurus. They were also prey items for scavenging pterosaurs like Azhdarcho, the swift and lethal Velociraptor, and probably even the regions apex predator, Tarbosaurus.

The first Mononykus fossils were found near the famous Flaming Cliffs in Mongolia during the 1920s, but it was not until 1922 that more complete skeletal material was discovered and the animal could be named.

In 1993, Mononykus was originally named Mononychus, but later that year, it was renamed because the original name had already been used for a beetle named by Johann Schueppel, a German entomologist.

Physical AttributesEdit

Mononykus WWD

Mononykus was a small dinosaur, standing over 3 feet (1 m) tall, measuring 6 feet (2 m) long, and weighing around 80 pounds (36 kgs).

The biggest mystery surrounding Mononykus is the single claws on its front limbs (similar to Tyrannosaurus). These had powerful muscles attached to them that would have made them very strong, but even so, scientists have not been able to find a practical use for these claws. They were too short to be of use in deference or for feeding, so perhaps they were used as part of a mating display. Given the strong muscles behind them, even a theory has its problems. It used to be thought that the claws would have been used for been explained.

Mononykus was very nimble and could run at high speeds, something that would have been useful in the open desert plains where it lived. It had a small skull and its teeth were small and pointed, suggesting that it mainly ate insects and small animals, such as lizards and mammals. Large eyes allowed Mononykus to hunt by night when it was cooler and there would have been fewer predators about.

Mononykus has proved to be something of a problem to science. Its skeleton has a remarkably bird-like sternum. In fact, Mononykus has so many bird-like qualities that there is an ongoing argument as to whether it is actually an unusual type of bird or an unusual type of theropod dinosaur. The issue has not yet been resolved, but whether it was a bird or a dinosaur, Mononykus is usually reconstructed with a covering of feathers.

Behavior & TraitsEdit

Mononykus lived in large groups and fed mainly on insects as well as dead carcasses. They also lived in forests and open areas. In life, these feathers would have provided Mononykus with insulation during colder months. They could also have provided it with camouflage, or perhaps have been used as part of a colorful mating display. When seeing the danger, Mononykus fled from whatever was attacking.


  • The sound effects of Mononykus are that of chicken, coyote, donkey, hyena, ostrich, and zebra sound effects.
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