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Re: A long-tailed bird with a pygostyle



I've asked Lu for a pdf.  If anyone has access (and please tell me if you
do), it can be downloaded here-
http://www.wanfangdata.com.cn/qikan/periodical.Articles/dzxb-e/dzxb2005/0501
/0501mle.htm

Mickey Mortimer
Undergraduate, Earth and Space Sciences
University of Washington
The Theropod Database - http://students.washington.edu/eoraptor/Home.html

----- Original Message -----
From: "Brad McFeeters" <archosauromorph2@hotmail.com>
To: <dinosaur@usc.edu>
Sent: Friday, April 08, 2005 6:05 PM
Subject: A long-tailed bird with a pygostyle


> Lü, Junchang & Lianhai Hou, 2005.  A possible long-tailed bird with a
> pygostyle from the late Mesozoic Yixian Formation, western Liaoning,
China.
> Acta Geologica Sinica 79 (1): 7-10.
>
> Abstract:  An incomplete caudal vertebral series (IVPP V11309) from the
> Yixian Formation of late Mesozoic, Jianshangou area of Beipiao, western
> Liaoning Province, may represent a new bird. The tail is composed of at
> least 12 free caudal vertebrae and the most distal 5 caudal vertebrae
> co-ossified into a pygostyle. The pygostyle is plate-like and slightly
> curved dorsally. The anterior free caudals are amphiplatyan. The anterior
> caudal surfaces of the last three free caudals are concave, but their
> posterior articular surfaces are convex. The pygostyle is regarded as the
> first appeared flight apparatus during the evolutionary process from
> *Archaeopteryx* to neornithes. The pygostyle appeared in most early fossil
> birds and almost all the modern birds. Although their morphologies are
> different, they are basically formed by at least four last caudal
vertebrae.
> The specimen V11309 is regarded as a bird rather than a non-avian theropod
> dinosaur based on the following characters: short caudal vertebrae,
numerous
> pits present on the surfaces of the centra and, a foramen present between
> the basal part of the fused neural spines, which is similar to that of
> *Struthio camelus*. The discoveries of pygostyles from the
therizinosauroids
> and oviraptorosaurs may provide strong evidence for supporting the origin
of
> birds from small theropod dinosaurs. The structure of the pygostyle in
> specimen V11309 is different from those of *Beipiaosaurus*
> (Therizinosauroid) and *Nomingia* (oviraptorosaur). The most parsimonious
> interpretation is that these pygostyle-like structures are independently
> acquired by *Beipiaosaurus* and *Nomingia* during their evolutionary
> process.
>
> Looks like no new taxon named this time, but I cannot be sure having seen
> only the abstract.
>
>
>