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Matt A. White Alex G. Cook Scott A. Hocknull David A. Elliott 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):435-441
WHITE, M.A., FALKINGHAM, P.L., COOK, A.G., HOCKNULL, S.A. & ELLIOTT, D.A., 2013. Morphological comparisons of metacarpal I for Australovenator wintonensis and Rapator ornitholestoides: implications for their taxonomic relationships. Alcheringa 37, 1 - 7. ISSN 0311-5518.Various comparisons of left metacarpal I of the Australovenator wintonensis holotype have been made with Rapator ornitholestoides. These specimens were identified as being morphologically more similar than either was to that of the neovenatorid Megaraptor namunhuaiquii. Owing to the poor preservation of A. wintonensis and R. ornitholestoides, distinct morphological separation between the two appeared minimal. The recent discovery of a near perfectly preserved right metacarpal I of A. wintonensis enables a direct and accurate comparison with R. ornitholestoides. Distinct morphological differences exist between the metacarpals of the two species. A re-evaluation of the age of the A. wintonensis holotype site (AODL 85 ‘Matilda Site’) with zircon dating reveals a maximum age of 95 Ma, 10 Ma younger than the Griman Creek Formation at Lightning Ridge, from which R. ornitholestoides was recovered. This age difference detracts from the probability that the specimens belong to the same genus.Matt A. White? [fossilised@hotmail.com], School of Engineering, The University of Newcastle, Callaghan, New South Wales 2308, Australia; Peter L. Falkingham? [pfalkingham@rvc.ac.uk], Department of Comparative Biomedical Sciences, Structure and Motion Laboratory, Royal Veterinary College, London, UK; Alex G. Cook [alex.cook@y7mail.com] and Scott A. Hocknull [scott.hocknull@qm.qld.gov.au], Ancient environments, Queensland Museum, Hendra, Queensland, 4011, Australia; David A. Elliott [david.elliott@aaod.com.au], Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland, 4735, Australia. ?Also affiliated with Australian Age of Dinosaurs Museum of Natural History, The Jump Up, Winton, Queensland 4735, Australia. ?Also affiliated with Department of Ecology and Evolutionary Biology, Division of Biology and Medicine, Brown University, USA. Received 22.9.2012; revised 13.1.2013; accepted 17.1.2013. 相似文献
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John G. Conran David C. Christophel 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):343-348
A new fossil triplinerved dicotyledon leaf, Laurophyllum acrocryptocaryoides Conran & Christophel (Lauraceae) from Eocene deposits at Nerriga is described. The fossil is similar to the previously described L. acrodromum Hill, also from this site, but differs in leaf shape and cuticular features. L. acrocrytocaryoides also resembles some members of the extant genus Cryptocarya and its relationship to extant taxa is discussed. 相似文献
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John G. Conran David C. Christophel 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):349-357
A monocotyledonous leaf macrofossil taxon from Golden Grove in Adelaide, South Australia is recognised as being close to several extant Australasian species of Cordyline, especially those in the C. stricta (Sims) Endl. / C. fruticosa (L.) A. Chev. complex. The fossil is assigned to the form genus Paracordyline, known previously from the Oligocene Kerguélen Islands. However, as the Golden Grove taxon differs markedly from the Kerguélen species, it is considered to be a new species, P. aureonemoralis Conran & Christophel. 相似文献
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