Kryostega was a species of amphibian that lived in Antarctica 240 million years ago. At 15 feet, it was the biggest predator of its enviroment. Its bones were originally found in 1986 but the species wasn't named until 2008. Kryostega likely occupied the same niche as crocodiles and normally would have eaten but also would have eaten a mammal-like reptile called Lystrosaurus
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