The plant eating creature lived in the valley that once existed between Australia and Antarctica and sheds new light on the diversity of the small, bipedal herbivorous dinosaurs called ornithopods.

The partial skeleton, named Diluvicursor pickeringi or Pickering's Flood-Running dinosaur, was found in sea cliffs near Cape Otway in the south eastern Australian state of Victoria.

It appeared to have become trapped in a log jam where it was immortalised, according to researchers.

Lead author palaeontologist Dr Matt Herne said "Diluvicursor shows for the first time that there were at least two distinct body-types among closely related ornithopods in this part of Australia.

"One was lightly built with an extraordinarily long tail, while the other, Diluvicursor, was more solidly built, with a far shorter tail.

"Our preliminary reconstruction of the tail musculature of Diluvicursor suggests this dinosaur was a good runner, with powerful leg retracting muscles.

"Understanding the ecology of these dinosaurs - what they ate, how they moved, where they roamed - based on the interplay between anatomy and the environment presents exciting challenges for future research."

The fossilised tail and foot bones were found by volunteer prospector George Caspar, eroding from a rock platform at a locality called Eric the Red West, near Cape Otway, in 2005.

Lower Cretaceous rocks of the deep sedimentary basins that formed within the Australian-Antarctic rift are now exposed as wave-cut rock platforms and sea-cliffs along the south coast of Victoria.

The new species was named in honour of David Pickering, who was Museums Victoria's Collection Manager, Vertebrate Palaeontology.

He made significant contributions to Australian paleontology in the lab and field, and tirelessly assisted students of paleontology and researchers to achieve their goals. He passed away just over a year ago on Christmas Eve 2016.

The site of Eric the Red West has additional importance as it helps build a picture the ancient rift valley ecosystem. F

Fossil vertebrate remains at this site were buried in deep scours at the base of a powerful river, along with flood-transported tree stumps, logs and branches.

Dr Herne added: "The carcass of the Diluvicursor pickeringi holotype appears to have become entangled in a log-jam at the bottom of this river.

"The sizes of some of the logs in the deposit and the abundance of wood suggest the river traversed a well-forested floodplain.

"The logs preserved at the site are likely to represent conifer forests of trees within families still seen in Australia today.

"Much of the fossil vertebrate material from Eric the Red West has yet to be described, so further dinosaurs and other exciting animals from this site are now anticipated."

The study was published in the journal PeerJ.