The elaphrosaur, whose name means "light-footed lizard", was related to the Tyrannosaurus Rex and Velociraptor.

The five-centimetre (two-inch) vertebrae fossil was discovered during a dig near Cape Otway in Victoria in 2015.

It is the first elaphrosaur bone ever to be found in Australia.

The fossil was discovered by volunteer Jessica Parker, who was taking part in an annual dig led by Melbourne Museum.

At the time, it was thought to be from a flying reptile called a pterosaur. But when palaeontologists at Swinburne University in Melbourne studied the fossil further, they realised it was a delicately-built dinosaur.

"Elaphrosaurs had long necks, stumpy arms with small hands, and relatively lightly-built bodies," Dr Stephen Poropat said.

The fossil indicated the animal was about two metres (6.5ft) long. However, other fossils previously found in Tanzania, China and Argentina show that they could reach up to six metres in length.

Adult elaphrosaurs probably didn't eat much meat, Dr Poropat said.

"As dinosaurs go, they were rather bizarre. The few known skulls of elaphrosaurs show that the youngsters had teeth, but that the adults lost their teeth and replaced them with a horny beak. We don't know if this is true for the [Australian] elaphrosaur yet - but we might find out if we ever discover a skull," he said.

Cape Otway, where the fossil was located, is a rich area for discoveries. About a dozen animals and five dinosaur species have been identified there, according to ABC News. Those discovered include a plant-eating dinosaur found in 2018.