Sydney, Oct 21 (IANS) Researchers have discovered a new species of long-necked dinosaurs in northeastern Australia that could have arrived from South America 105 million years ago, officials said on Friday.

The Savannasaurus elliottorum were between 12-15 metres long with a long neck, a relatively short tail and hips around 1.5 metres wide, EFE news reported.

The Savannasaurus belong to a branch of the sauropods known as titanosaurs, the largest land animals to have inhabited the Earth, Stephen Poropat, of the Australian Age of Dinosaurs Museum of Natural History (AAOD), said.

The paleontologist, whose study was published in the journal Scientific Reports, said they could recover only 20-25 per cent of the Savannasaurus, mostly parts belonging to its torso, limbs and the pelvis.

"Because they are very large animals it would take a fair bit of sediment to bury it before predators come along," Poropat said.

He added that teeth of carnivorous dinosaurs were also found at the site, which suggests there might have been scavenging of the remains of the Savannasaurus.

The first fossils of these titanosaurs were found in 2005 by grazier David Elliot, the chairman of AAOD in Winston in Queensland state.

Shortly after the AAOD and the Queensland Museum began excavating the fossil site, but it was nearly a decade till they could remove the bones from the rocks in which they were encrusted.

Besides the Savannasaurus, Poropat also described another dinosaur in his study that was discovered in Australia in 2009, Diamantinasaurus matildae, whose excavation enabled the discovery of the first skull of a sauropod in the country.

The discovery of the Savannasaurus and the Diamantinasaurus have sparked a controversy over the origin of the titanosaurs in Australia.

Earlier studies on megafauna suggested they were similar to dinosaurs from Laurasia, the ancient supercontinental landmass in the Northern Hemisphere.

However, Poropat argued against that theory explaining that Laurasia and Gondwana - which gave rise to the continental masses of the Southern Hemisphere: South America, Africa, Australia and Antarctica - were separated.

According to the expert, the discovery shows the Savannasaurus and the Diamantinasaurus arrived from South America 105 million years ago through the Antarctica during an era of warmer temperatures and when the three continents were connected.