'Bizarre' Dinosaur That Lived Near the South Pole Discovered in Australia

A 110 million-year-old fossilized bone belonging to a "bizarre" dinosaur called an elaphrosaur has been discovered at a site in Victoria, Australia, suggesting it lived near the South Pole, say scientists.

Paleontologists writing in Gondwana Research say it is the first evidence of an elaphrosaur reported in Australia and only the second from the Cretaceous period worldwide.

The study's authors say the location of the discovery near Cape Otway in Victoria implies elaphrosaurs existed in this part of the world until at least the late Early Cretaceous, around 110 to 107 million years ago.

It also suggests the dinosaur was able to survive in "pole-like conditions," albeit ice-free poles that were far more temperate than they have been in modern times. Though much closer to the equator today, the landmass was significantly closer to the South Pole 110 million years ago. According to the study's authors, it would have been 76 degrees south of the Earth's equatorial plane, where parts of Antarctica lie today.

"Elaphrosaurs had long necks, stumpy arms with small hands, and relatively lightly built bodies," Swinburne palaeontologist Dr. Stephen Poropat said in a press release. "As dinosaurs go, they were rather bizarre."

Elaphrosaurs—which means "light-footed lizards"—were a group of theropods related to the Tyrannosaurus rex, Velociraptor and modern birds.

Unlike some of their relatives, elaphrosaurs remains are relatively scarce. According to the study's authors, one explanation for their scant presence on the fossil record is that they are "hiding in plain sight" and are frequently misidentified as other clades, as was the case in this instance when it was confused for a pterosaur.

Illustration: elaphrosaur
An artist’s impression of what an elaphrosaur may have looked like. Scientists have discovered the first bone of a elaphrosaur in Australia. Ruairidh Duncan

From the few skulls known to exist, paleontologists believe the young had teeth, which were lost and replaced by a horny beak as they get older. "We don't know if this is true for the Victorian elaphrosaur yet—but we might find out if we ever discover a skull," said Poropat.

"Young elaphrosaurs might have hunted the tiny monotremes (ancestors to platypus and echidna) that lived in polar Victoria, along with snapping up insects and fruits," Tim Ziegler, Collection Manager of Vertebrate Palaeontology at Museums Victoria who was not involved in the study, said in a statement.

This particular individual would have been on the small-side at just 2-meters long. According to the study's authors, it was also comparatively young. Relatives including Elaphrosaurus from Tanzania and Limusaurus from China date back to the Jurassic Period (160–145 million years ago). In contrast, the remains discovered in Victoria date to the Early Cretaceous Period, 40 million years later.

The fossil—a 2-inch (5-centimeter) bone—was found by Dinosaur Dreaming volunteer Jessica Parker in 2015, during a dig at a fossil site near Cape Otway called Eric the Red West.

Jessica Parker with the vertebra she found
Jessica Parker with the vertebra she found at Melbourne Museum. via Museums Victoria

After determining the fossil did not belong to a pterosaur as first thought—the fossil had sockets at both end, whereas pterosaur vertebra only have one—some thorough investigation revealed the most likely contender was an elaphrosaur: "We soon realised that the neck bone we were studying was from a theropod: a meat-eating dinosaur, related to Tyrannosaurus rex, Velociraptor, and modern birds," said Poropat.

According to the study's authors, this discovery combined with previous findings suggests the remains of elaphrosaurs may be found in early- to mid-Cretaceous deposits elsewhere.

"New discoveries like this elaphrosaur fossil overturn past ideas, and help to interpret discoveries yet to come," said Ziegler.

Elaphrosaur vertebra
The Elaphrosaur vertebra was found at Eric the Red West, a fossil site in Victoria. Ruairidh Duncan; C Museums Victoria