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Re: Piksi a pterosaur, not a bird from Upper Cretaceous



_Piksi_, _Eurolimnornis_ and  _Palaeocursornis_ add to a growing list
of Mesozoic "birds" that have been re-classified as pterosaurs:
_Cimoliornis_, _Cretornis_, _Palaeornis_, _Laopteryx_, _Samrukia_.
There might be others.


I can't think of too many examples in the opposite direction (i.e.,
originally thought to be a pterosaur, then re-classified as a bird).
Though I guess _Pterodactylus crassipes_ counts (later referred -->
_Archaeopteryx_).


There are worse examples of mis-classification regarding Mesozoic
"birds".  _Priscavolucris_ was originally regarded as a Jurassic bird;
it was subsequently re-identified as a Cretaceous shark!




On Sat, Dec 29, 2012 at 4:17 AM, Ben Creisler <bcreisler@gmail.com> wrote:
> From: Ben Creisler
> bcreisler@gmail.com
>
> A new paper. The pdf is free.
>
> F. L. Agnolin & D. Varricchio (2012)
> Systematic reinterpretation of Piksi barbarulna Varricchio, 2002 from
> the Two Medicine Formation (Upper Cretaceous) of Western USA (Montana)
> as a pterosaur rather than a bird.
> Geodiversitas 34 (4): 883-894.
> http://dx.doi.org/10.5252/g2012n4a10
> free pdf:
> http://www.mnhn.fr/museum/front/medias/publication/48099_g2012n4a10.pdf
>
> Varricchio (2002) described some forelimb bones from the Late
> Cretaceous (Campanian) Two Medicine Formation, Glacier County, Montana
> (USA), as the holotype of Piksi barbarulna, a supposed
> ornithothoracine bird. However reevaluation of Piksi Varricchio, 2002
> instead recognizes this genus as belonging to Pterosauria Kaup, 1834
> and not Aves Linnaeus, 1758. Piksi exhibits the following derived
> humeral traits of pterosaurs: 1) very large ectepicondyle; 2) large
> trochlea; 3) with a deep, wide and poorly deliminated brachial
> depression that is proximodistally extended; 4) a wide and deep
> olecranal fossa not marked dorsally by a ridge; and 5) lacking a
> distal depression of the groove for the m. humerotricipitalis.
> Moreover, the putative Early Cretaceous birds Eurolimnornis Jurcsák &
> Kessler, 1986 and Palaeocursornis Jurcsák & Kessler, 1986, based on
> distal humeri, are also regarded as pterosaurs. The record of Piksi
> constitutes an important addition to the Latest Cretaceous
> pterosaurian record.