Huge Titanosaur From 90 Million Years Ago Is Among 15 Largest Dinosaurs Ever Unearthed

Researchers have officially recognized a newly identified dinosaur species as being among the top 15 largest dinosaurs ever discovered worldwide based on skeletal measurements.

Remains of the dinosaur were first uncovered in 2006 west of Eromanga, in the northeastern state of Queensland, Australia. They represent the largest skeletal remains of a dinosaur ever to be discovered in the country.

After 15 years of painstaking excavation, palaeontologists from the Queensland Museum, the Eromanga Natural History Museum and the University of Melbourne have finally described the dinosaur scientifically in a paper published in the open-access journal PeerJ, naming it Australotitan cooperensis.

Bases on the prepared remains of the skeleton, which has been dated to approximately 92-96 million years ago, the authors of the study estimate that the species could reach 25-40 meters (about 82-131 feet) in length and 5-6.5 meters (about 16-21 feet) high from ground to hip.

While determining the potential mass of Australotitan is very difficult, the researchers estimated that it could have been between 23,000-74,000 kilograms (23-82 tons).

Australotitan is a sauropod—a group of herbivorous dinosaurs with very long necks, long tails, small heads and four thick legs, which boasted among them some of the largest animals to ever roam the Earth on land.

The new species belongs to a sauropod subgroup known as the Titanosaurians. The researchers found that it was closely related to three other sauropod species found in the same geological layer, known as the Winton Formation.

"We compared the three species found to the north, near Winton, to our new Eromanga giant and it looks like Australia's largest dinosaurs were all part of one big happy family," Scott Hocknull, a palaeontologist at the Queensland Museum, said in a statement issued Monday.

"We found that Australotitan was the largest in the family, followed by Wintonotitan with big hips and long legs, whilst the two smaller sauropods, Diamantinasaurus and Savannasaurus were shorter in stature and heavily-set."

"Australotitan adds to the growing list of uniquely Australian dinosaur species discovered in Outback Queensland, and just as importantly showcases a totally new area for dinosaur discovery in Australia," he said.

The dinosaur was first uncovered on the family property of husband and wife Robyn and Stuart Mackenzie, who are are co-founders of the Eromanga Natural History Museum, as well as authors on the new study. The remains of around 15 dinosaurs have since been found on the property Robyn Mackenzie told The Guardian. The specimen was nicknamed "Cooper" after the nearby freshwater Cooper Creek.

"Finding Cooper has changed the course of our lives and led to the establishment of the Eromanga Natural History Museum," Robyn Mackenzie said in the Queensland Museum statement.

"Working with Queensland Museum to formally describe Cooper has helped put our little town of Eromanga in Quilpie Shire, southwest Queensland on the map. Australotitan is just the start, we have many more discoveries awaiting full scientific study.

 Vlad Konstantinov/Queensland and Eromanga Natural History museums
Artist's reconstruction of "Australotitan cooperensis." Vlad Konstantinov/Queensland and Eromanga Natural History museums