Australovenator

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Australovenator
Temporal range: Early Cretaceous,[1] 95Ma
Restoration of the skeleton, Australian Age of Dinosaurs Museum, Winton, Australia
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Theropoda
Clade: Megaraptora
Genus: Australovenator
Hocknull et al., 2009
Species: † A. wintonensis
Binomial name
Australovenator wintonensis
Hocknull et al., 2009

Australovenator (meaning "southern hunter") is a genus of either allosauroid or tyrannosauroid theropod dinosaurs from Albian (Early Cretaceous)-age rocks (dated to 95 million years ago[1]) of Australia. It is known from partial cranial and postcranial remains which were described in 2009 by Dr Scott Hocknull and colleagues.

Description and history[edit]

Silhouette with known skeletal elements
Life restoration

Australovenator is based on AODL 604 (affectionately named "Banjo" after Banjo Paterson[2]) a partial skeleton including a left dentary, teeth, partial forelimbs and hindlimbs, a partial right ilium, ribs, and gastralia. Australovenator was described in 2009 by paleontologist Scott Hocknull of the Queensland Museum, and colleagues. The type species is A. wintonensis, in reference to nearby Winton. A phylogenetic analysis found Australovenator to be an allosauroid carnosaurian, with similarities to Fukuiraptor and carcharodontosaurids. In the initial analysis, it was shown to be the sister taxon of the Carcharodontosauridae.[3] More detailed studies found that it formed a clade with several other carcharodontosaurid-like allosaurs, the Neovenatoridae.[4]

The ankles of Australovenator and Fukuiraptor are similar to the Australian talus bone known as NMVP 150070 that had previously been identified as belonging to Allosaurus sp., and this bone likely represents Australovenator or a close relative of it.[3][5] Alternatively, this bone could belong to an abelisaur.[6]

More arm elements of the holotype were described in 2012.[7]

Paleobiology[edit]

Life restoration of Australovenator feeding on carcass of Diamantinasaurus

AODL 604 was found about 60 kilometres (37 mi) northwest of Winton, near Elderslie Station. It was recovered from the lower part of the Winton Formation, dated to the latest Albian. AODL 604 was found in a clay layer between sandstone layers, interpreted as an oxbow lake, or billabong, deposit. Also found at the site were the type specimen of the sauropod Diamantinasaurus, bivalves, fish, turtles, crocodilians, and plant fossils. The Winton Formation had a faunal assemblage including bivalves, gastropods, insects, the lungfish Metaceratodus, turtles, the crocodilian Isisfordia, pterosaurs, and several types of dinosaurs, such as the sauropods Diamantinasaurus and Wintonotitan, and unnamed ankylosaurians and hypsilophodonts. Plants known from the formation include ferns, ginkgoes, gymnosperms, and angiosperms.[3]

Australovenator was a medium-sized allosauroid.[3] According to Hocknull, it was 2 m (6.6 ft) tall at the hip and 6 m (20 ft) long, with a weight of about 500-1000 kg. Because it was a lightweight predator, he coined it as the "cheetah of its time".[8] Like other carnosaurians, Australovenator would have been a bipedal carnivore.[9] Recent phylogenetic analysis suggests Australovenator is a tyrannosauroid, like with all other megaraptorans.[10]

References[edit]

  1. ^ a b White, M. A.; Falkingham, P. L.; Cook, A. G.; Hocknull, S. A.; Elliott, D. A. (2013). "Morphological comparisons of metacarpal I forAustralovenator wintonensisandRapator ornitholestoides: Implications for their taxonomic relationships". Alcheringa: an Australasian Journal of Palaeontology: 1. doi:10.1080/03115518.2013.770221.  edit
  2. ^ Australovenator on prehistoric-wildlife.com
  3. ^ a b c d Hocknull, Scott A.; White, Matt A.; Tischler, Travis R.; Cook, Alex G.; Calleja, Naomi D.; Sloan, Trish; Elliott, David A. (2009). "New Mid-Cretaceous (Latest Albian) Dinosaurs from Winton, Queensland, Australia". In Sereno, Paul. PLoS ONE 4 (7): e6190. Bibcode:2009PLoSO...4.6190H. doi:10.1371/journal.pone.0006190. PMC 2703565. PMID 19584929. 
  4. ^ Benson, R.B.J.; Carrano, M.T; Brusatte, S.L. (2010). "A new clade of archaic large-bodied predatory dinosaurs (Theropoda: Allosauroidea) that survived to the latest Mesozoic". Naturwissenschaften 97 (1): 71–78. Bibcode:2010NW.....97...71B. doi:10.1007/s00114-009-0614-x. PMID 19826771. 
  5. ^ Molnar, Ralph E.; Flannery, Timothy F.; Rich, Thomas H.V. (1981). "An allosaurid theropod dinosaur from the Early Cretaceous of Victoria, Australia". Alcheringa 5 (2): 141–146. doi:10.1080/03115518108565427. 
  6. ^ Agnolin, F. L.; Ezcurra, M. D.; Pais, D. F.; Salisbury, S. W. (2010). "A reappraisal of the Cretaceous non-avian dinosaur faunas from Australia and New Zealand: Evidence for their Gondwanan affinities". Journal of Systematic Palaeontology 8 (2): 257–300. doi:10.1080/14772011003594870. 
  7. ^ White, M. A.; Cook, A. G.; Hocknull, S. A.; Sloan, T.; Sinapius, G. H. K.; Elliott, D. A. (2012). "New Forearm Elements Discovered of Holotype Specimen Australovenator wintonensis from Winton, Queensland, Australia". In Dodson, Peter. PLoS ONE 7 (6): e39364. doi:10.1371/journal.pone.0039364.  edit
  8. ^ Scientists discover 3 new Aussie dinosaurs. ABC News. July 3, 2009
  9. ^ Holtz, Thomas R., Jr.; Molnar, Ralph E.; Currie, Philip J. (2004). Weishampel, David B.; Dodson, Peter; and Osmólska, Halszka (eds.), ed. The Dinosauria (2nd ed.). Berkeley: University of California Press. pp. 71–110. ISBN 0-520-24209-2. 
  10. ^ F. E. Novas, F. L. Agnolín, M. D. Ezcurra, J. I. Canale, J. D. Porfiri (2012). "Megaraptorans as members of an unexpected evolutionary radiation of tyrant-reptiles in Gondwana". Ameghiniana 49 (Suppl.): R33.