[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Ceratosaurian astragalocalcaneum from Australia



What is *Ozraptor* now thought to be?

----------------------------------------
> Date: Sun, 6 May 2012 19:18:19 -0700
> From: bcreisler@gmail.com
> To: dinosaur@usc.edu
> Subject: Ceratosaurian astragalocalcaneum from Australia
>
> From: Ben Creisler
> bcreisler@gmail.com
>
>
> A new online paper:
>
>
> Erich M. G. Fitzgerald, Matthew T. Carrano, Timothy Holland, Barbara
> E. Wagstaff, David Pickering, Thomas H. Rich and Patricia Vickers-Rich
> (2012)
> First ceratosaurian dinosaur from Australia.
> Naturwissenschaften (advance online publication)
> DOI: 10.1007/s00114-012-0915-3
> http://www.springerlink.com/content/n6564767577306m3/
>
>
> The basal theropod dinosaur clade Ceratosauria, and its subclade
> Abelisauroidea, is characteristic of late Mesozoic terrestrial
> vertebrate faunas in western Gondwana (South America, Africa,
> Madagascar, and India) and Europe. Yet unambiguous records of
> ceratosaurs have hitherto been absent from Australia, where the
> theropod assemblage appears to include several typically Laurasian
> clades. Here, we report the first evidence of ceratosaurs (and
> potentially abelisauroids) from eastern Gondwana––a diagnostic
> astragalocalcaneum from the Aptian (121–125 Ma) of Victoria,
> Australia. Ceratosauria thus occurred in both western and eastern
> Gondwana during the Early Cretaceous. This fossil adds to the poorly
> known dinosaur fauna of Australia, a major clade of basal theropods,
> emphasising that its mid-Cretaceous theropod diversity was
> surprisingly cosmopolitan despite relative geographic isolation,
> including clades that have been thought to be typical of both Gondwana
> and Laurasia––Ceratosauria, Spinosauridae, Carcharodontosauria,
> Tyrannosauroidea, and Deinonychosauria. Such a contemporaneous
> association of theropod clades is unknown from other Gondwanan
> continents and questions the views that the late Mesozoic dinosaur
> fauna of Australia was dominated by Gondwanan or Laurasian elements,
> extreme isolation, relictualism, and/or novelty as a ‘centre of
> origin’. The cosmopolitan theropod fauna of Australia probably
> reflects the global distribution of these clades early in their
> history, prior to significant continental breakup.