A new species of dinosaur, the Rain Lizard, has made its debut in the growing catalogue of exciting fossil finds in the Free State.

The main characteristic of the Rain Lizard or, Pulanesaura eocollum, an ancestor of the enormous Brontosaurus, is that it would have spent its time on all fours, browsing lower vegetation.

Other sauropods - long necked dinosaurs - would have relied on their forelimbs to gather food from the forest canopy.

University of the Witwatersrand PhD student Blair McPhee described it as a new species after he and Dr Jonah Choiniere, from the Evolutionary Studies Institute at Wits University in Johannesburg worked with a team unravelling the mysteries of the ancient creatures.

Choiniere told News24 the find and the final description shows the first evidence of dinosaurs making the transition to walking on four legs, and browsing on the ground.

As a relatively small sauropod, it would have been about eight metres in length, two metres at the hips, and 5 t in body mass.

Choiniere said paleontologist Bruce Rubidge found a site on the farm Heelbo near Senekal that showed promise of dinosaur remains during a walk over the Christmas holidays many years ago.

Later, a graduate student John Hancox was looking for a project, so Rubidge and fellow paleontologist James Kitching took him to the site in 2005.

Hancox "wandered off, as students do" and suddenly returned saying "there is a mass of dinosaur bones there". Hancox's project changed, and he eventually went on to teach geology at Wits and then went into the industry.

But not before taking Choiniere's predecessor Dr Adam Yates, now at the Museum of Central Australia, to the spot. Yates and colleague Dr Matt Bonnan started digging and the slow, painstaking work of taking the fossils to the laboratory, cleaning and studying them, took around ten years.

They were convinced that what they had found was different to the dinosaurs that had roamed the area around 200-million years ago.

"Adam always talked about these bones - he said they were different," said Choiniere.

Final pieces of the puzzle

Yates moved to Australia, and the work was handed over to Choiniere. Enter another graduate student, McPhee, and the final pieces of the puzzle were put in place.

Geologist Dr Johann Neveling from the Council for Geoscience's job was to study the locality where the Rain Lizard was found.

Neveling, who is the hero of his young nephews after showing them a real dinosaur bone, told News24 that there were more channel deposits there which showed evidence of a lot more water flow than elsewhere.

"There are plants that collect along the river bank and this would have supported larger animals," he said. He explained that because of the river and its plants, the dinosaurs started feeding differently and more efficiently.

It wasn't until 2010 that Pulanesaura finally got its name. It is derived from Pulane, the childhood Sesotho nickname of Panie, the daughter of the late Naude Bremer whose farm the bones were found on. Heelbo has already revealed Aardonyx and Arcusaurus, both more primitive members of the same lineage of dinosaurs.

Wits added that translated, "Pulane" means "comes with rain", and Pulanesaura was excavated during a rainy period on the farm.

In a taster of the paper authored by McPhee, Bonnan, Choiniere, Yates and Neveling, McPhee says: "This dinosaur showcases the unexpected diversity of locomotion and feeding strategies present in South Africa 200-million years ago. This has serious implications for how dinosaurs were carving up their ecosystems."

News24.com