Koolasuchus ("Kool's Crocodile") was a giant temnospondyl amphibian (almost as big as the modern American crocodile and bigger than any of the modern amphibians) that lived in the Mid-Cretaceous period (106 MYA).
Koolasuchus lived in Antarctican during the Middle Cretaceous period over 106 million years ago.
Koolasuchus was a carnivorous amphibian that measured 4 meters long and weighed half a ton. They also had massively powerful jaws.
These bizarre looking creatures were relics from a time before dinosaurs. During their time, in most parts of the world, competition from crocodiles had begun to drive these magnificent amphibians to extinction. But in prehistoric Antarctica, the waters got too cold for crocodiles and the world's last Koolasuchus survived, still patrolling the waterways, just as their ancestors did 150 million years before them.
In the water Koolasuchus was lethal, but on land their legs had trouble dragging their bulk around…and they were no threat to even the little dinosaurs. During winter, they hibernated in swamps in forests and spent their summer in rivers.