Rauisuchus was a basal archosaur

Archosaur

Archosaurs are a group of diapsid amniotes whose living representatives consist of modern birds and crocodilians. This group also includes all extinct non-avian dinosaurs, many extinct crocodilian relatives, and pterosaurs. Archosauria, the archosaur clade, is a crown group that includes the most...

 which lived in what is now the Geopark

Geopark

A Geopark is defined by the United Nations Educational, Scientific and Cultural Organization in its UNESCO Geoparks International Network of Geoparks programme as follows:...

 of Paleorrota

Paleorrota

Paleorrota , is a geopark located in the center of the Brazilian state of Rio Grande do Sul. The rocks and fossils found along the route date back to the times when there was only one supercontinent Pangaea....

, Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

, during the middle Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 period (240-230 million years ago). Named after fossil collector Dr. Wilhelm Rau, Rauisuchus belonged to a group of land-dwelling relatives to crocodiles. These reptiles were among the top predators of their day, eating other reptiles for food and maybe hunting early dinosaurs.

Rauisuchus grew to a length of 13 feet (4 m) and was 3 feet (90 cm) high at the hips. It had a weight of around 550 lbs (250 kg).