Australia: The Land Where Time Began
Late Cretaceous Dinosaurs
In the Winton Formation, Queensland, sauropods are the most common type of dinosaur present. Many vertebrae, limb bones and girdles are present that have been attributed to Titanosauriforms, that were the dominant group of Late Cretaceous sauropods from Gondwana. Wintonotitan, a primitive titanosaurian with affinities that are uncertain, and Diamantinasaurus matildae, more advanced and possibly related to saltasaurids, bizarre armoured dinosaurs that are known best in the South American cretaceous, are at least 2 new taxa present. Wintonotitan and Diamantinasaurus were both very large animals that grew up to 25 m long. It is suggested by these finds and a possible 3rd sauropod taxon, not yet described, that the lowland floodplains of central Queensland supported a surprisingly diverse assemblage of mega-herbivores about 100 Ma.
Among other body fossils of dinosaurs from the Winton Formation were small and large ornithopods, known only from isolated teeth, phalanges, limb bones and vertebrae. Theropods appear to have been rare, with only a few isolated teeth and a partial skeleton that was found near Winton, Australovenator wintonensis, a medium sized dinosaur about 4-5 long, is the most complete carnivorous dinosaur found in Australia at the time of writing. The parts of this specimen that have been found include elements of the fore- and hind limbs, part of the pelvis, some ribs, lower jaw, and some loose teeth. It was lightly built and is believed to have been a theropod that could run fast, and on its hands were enlarged cycle-shaped claws. The authors3 suggest it may have used its hooked claws to grapple with prey, though there is evidence that indicates it may have also been a scavenger as it has been found in association with a massive sauropod. Australovenator is believed to have been a primitive carcharodontosaurid, a group of allosauroids that are found predominantly in Gondwana, including some forms from South America and Africa that were larger than Tyrannosaurus of North America. Australovenator is most closely related to allosauroids from the Northern Hemisphere, England and Japan, the authors3 suggesting that this implies a distribution that is near global for allosauroids during the Early-Middle Cretaceous.
See Lark Quarry
In the marine Molecap Greensand deposit and Miria Formation isolated dinosaur fossils from the Upper Cretaceous have been found that are believed to have been dinosaur carcasses that floated out to sea. Among the fossils found are a theropod toe-bone that is allosaurid-like from the Molecap Greensand at Molecap Hill Quarry near Gingin. A large humerus 210 mm long has been recovered from the Miria Formation in the Giralia Ranges that displays similarities to the humerus of tetanuran theropods and dromaeosaurs.
|Author: M.H.Monroe Email: email@example.com Sources & Further reading