Nothronychus with claws raised in defence


Nothronychus are related to some dinosaurs with ferocious reputations, like the carnivorous tyrannosaurs and allosaurs. But these weren't meat-eaters at all, they had evolved to eat plants. These enigmatic and bizarre-looking theropod dinosaurs had a pot-belly, long arms and agile hands with impressive 30cm long claws. They could have been used to pull down branches to reach the leaves or strip bark from trees.

The wicked looking claws may also have defended Nothronychus from predators or fend off rivals. Nothronychus was the first member of the therizinosaur family to be found in the Americas. Most of the others, such as Therizinosaurus, have been found in China and Mongolia.

Scientific name: Nothronychus

Rank: Genus

Common names:

slothful claw

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Discover what these behaviours are and how different plants and animals use them.

Additional data source: Animal Diversity Web

When they lived

Discover the other animals and plants that lived during the following geological time periods.

Cretaceous period Cretaceous period
The Cretaceous ended with the most famous mass extinction in history - the one that killed the dinosaurs. Prior to that, it was a warm period with no ice caps at the poles.

What killed them

Cretaceous-Tertiary mass extinction Cretaceous-Tertiary mass extinction
The Cretaceous-Tertiary mass extinction - also known as the K/T extinction - is famed for the death of the dinosaurs. However, many other organisms perished at the end of the Cretaceous including the ammonites, many flowering plants and the last of the pterosaurs.