Friday, July 03, 2009

New Australian Dinosaurs


Scientists have confirmed for the first time that Australia was once home to a dinosaur that was big, fast and terrifying, and they've named it like something from an Arnold Schwarzenegger movie. Meet the Australovenator.

The beast was a 1,100 pound (500 kilogram) meat-eating predator with three slashing claws on each of its powerful forelimbs that stalked the Outback 98 million years ago, researchers said in a report published Friday.

Fossilized remnants of its limb bones, ribs, jaw and fangs were found — along with bones of two other new species of gigantic, long-necked herbivores weighing up to 22 tons (20 metric tons) — in Queensland state over the past three years.

The discovery, analyzed in a 51-page report published in the peer-reviewed online science journal PLoS ONE, was the first substantial find of large dinosaurs in Australia to be revealed in 28 years.

[...]

The finders nicknamed the 16-foot (5-meter) long carnivore, Australovenator wintonensis (pronounced oss-tra-low-VEN'-ah-tor win-TON'-en-sis), "Banjo," after the poet A.B. "Banjo" Paterson who in 1885 penned Australia's unofficial anthem "Waltzing Matilda" on a sheep ranch near Winton — a cattle town that lies closest to where the dinosaur bones were found. Banjo's Latin name means "Winton's Southern Hunter."

"The cheetah of his time, Banjo was light and agile," the report's lead author, Scott Hocknull, a Queensland Museum paleontologist, said in a statement.

"He's Australia's answer to Velociraptor, but many times bigger and more terrifying," Hocknull added, referring to the turkey-sized prehistoric predators recreated with artistic license in the "Jurassic Park" movies.

The other two finds — 52-foot- (16-meter-) long herbivores — were previously unknown types of titanosaur, the largest dinosaurs that ever lived. The giraffe-like Wintonotitan wattsi (pronounced win-ton-oh-TIE-tan wot-SIGH) and nicknamed Clancy translates from Latin as "Watts' Winton Giant." The Diamantinasaurus matildae (pronounced dye-man-TEEN'-ah-sor-us mah-TIL'-day) resembled a hippopotamus and has been nicknamed Matilda; the Latin name translates as "Matilda's Diamantina River Lizard."


Paper link is here.

New Mid-Cretaceous (Latest Albian) Dinosaurs from Winton, Queensland, Australia

Scott A. Hocknull (a*)
Matt A. White (b)
Travis R. Tischler(b)
Alex G. Cook(a)
Naomi D. Calleja(b)
Trish Sloan(b)
David A. Elliott(b)

a Geosciences, Queensland Museum, Hendra, Queensland, Australia

b Australian Age of Dinosaurs Museum of Natural History, The Jump-up, Winton, Queensland, Australia

Abstract:

Background

Australia's dinosaurian fossil record is exceptionally poor compared to that of other similar-sized continents. Most taxa are known from fragmentary isolated remains with uncertain taxonomic and phylogenetic placement. A better understanding of the Australian dinosaurian record is crucial to understanding the global palaeobiogeography of dinosaurian groups, including groups previously considered to have had Gondwanan origins, such as the titanosaurs and carcharodontosaurids.
Methodology/Principal Findings

We describe three new dinosaurs from the late Early Cretaceous (latest Albian) Winton Formation of eastern Australia, including; Wintonotitan wattsi gen. et sp. nov., a basal titanosauriform; Diamantinasaurus matildae gen. et sp. nov., a derived lithostrotian titanosaur; and Australovenator wintonensis gen. et sp. nov., an allosauroid. We compare an isolated astragalus from the Early Cretaceous of southern Australia; formerly identified as Allosaurus sp., and conclude that it most-likely represents Australovenator sp.
Conclusion/Significance

The occurrence of Australovenator from the Aptian to latest Albian confirms the presence in Australia of allosauroids basal to the Carcharodontosauridae. These new taxa, along with the fragmentary remains of other taxa, indicate a diverse Early Cretaceous sauropod and theropod fauna in Australia, including plesiomorphic forms (e.g. Wintonotitan and Australovenator) and more derived forms (e.g. Diamantinasaurus).




Perhaps Australia wasn't as much of a refugium as people - including me - have thought. Perhaps the difference in fauna - labrynthodonts, possibly dicynodonts, etc - are just a case of a different locale's fauna. huh. Wouldn't be funny if in Laurasia, in a polar region, there ended up being some dicynodonts and uber sized amphibians, too? And the only reason we don't know they are there is just sampling bias...huh. Interesting thought that.

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