Walking With Wikis

       Koolasuchus 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) and was featured in the 5th episode of Walking with Dinosaurs.


A giant amphibian of the Mid-Cretaceous, Koolasuchus had massively powerful jaws, weighed about half a ton…and were carnivores. 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. These bizarre looking creatures were relics from a time

A Koolasuchus going into a river

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 Walking with... Series

Walking with Dinosaurs

Spirits of the Ice Forest

In the beginning of the episode one Koolasuchus was shown eating a dead Leaellynasaura that died in winter. As the weather warmed up, the giant amphibian emerged from the pond and moved to a bigger river, startling more of Leaellynasaura. However, it was harmless to them on land and they soon ignored it.

Koolasuchus' size (4 m.) comparison with a modern crocodile (5 m.) and human (roughly 2 m.) from BBC WF site.

Later, more Koolasuchus appeared in the river and one of them tried to attack a Leaellynasaura youngster. However, even near water the dinosaur proved to be too fast for Koolasuchus and the attack failed.

When the autumn arrived once more, the first Koolasuchus returned back to the small pond to spend the winter there.