Steropodon (Steropodon galmani)
Steropodon.
Illustration: A Musser © Australian Museum.
Lived: 110 million years ago (early Cretaceous)
Size: Length (head to tail): 35cm
Description: Steropodon was a platypus-like mammal that lived alongside the dinosaurs. It spent most of its time in freshwater creeks and billabongs, probably eating yabbies and other small aquatic animals.
Steropodon is an egg-laying mammal, like today's Platypus and echidnas. The Platypus is probably Steropodon's closest living relative.
Fossils: An opalised jaw of Steropodon was found at Lightning Ridge in New South Wales. The jaw has three molar teeth. A couple of other partial jaws have also been found. Steropodon was named in 1985 and is regarded as one of Australia's most important fossil discoveries.
Did you know?: Steropodon was almost as big as some of the small dinosaurs it lived alongside at Lightning Ridge. It was one of the largest mammals in the world during the Cretaceous.
