Postosuchus with a kill


A cousin of modern crocodiles, Postosuchus was an archosaur - the lineage of reptiles that include the crocodiles, dinosaurs and birds. Reaching lengths of five metres, Postosuchus was the top predator during the Late Triassic in what's now the southern USA. Since its front limbs were shorter than its hind limbs, there is debate as to whether it walked on two legs or four, but most palaeontologists favour the latter. Its stance, with the legs under the body, would have made it a faster and more efficient runner than a modern crocodile. Most Postosuchus fossils have been found in Texas' Post quarry, hence the name.

Scientific name: Postosuchus

Rank: Genus

Common names:

crocodile from Post

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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.

Triassic period Triassic period
The Triassic began after the worst mass extinction ever, at the end of the Permian. Life on Earth took a while to recover and diversify.

What their world was like

Desert Earth Desert Earth
A vast desert formed in Earth's prehistoric past when the supercontinent of Pangaea straddled the equator and stretched to the poles. Pangaea's position influenced ocean circulation patterns, and its huge size meant that there were vast areas where moist air from the oceans never penetrated.

What killed them

Triassic-Jurassic mass extinction Triassic-Jurassic mass extinction
During the final 18 million years of the Triassic period, there were two or three phases of extinction whose combined effects created the Triassic-Jurassic mass extinction event. Climate change, flood basalt eruptions and an asteroid impact have all been blamed for this loss of life.


  1. Life
  2. Animals
  3. Vertebrates
  4. Reptiles
  5. Rauisuchia
  6. Rauisuchidae
  7. Postosuchus