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A therizinosauroid dinosaur with integumentary structures from China



It's official.  The May 27, 1999 issue of _Nature_ features the above named 
paper,
authored by Xing Xu, Zhi-Lu Tang, and Xiao-Lin Wang, which describes a
therizinosauroid specimen, named _Beipiaosaurus inexpectus_, which is estimated 
to
have a length (in life) of 2.2 meters, and which features the remains of
integumentary filaments resembling those of _Sinosauropteryx prima_, which are 
up
to 70 mm in length (the average fiber length being 50 mm).  The specimen, which
was discovered in 1996, is far from complete, but contains a number of 
articulated
bone pieces.  It gives us more precious information on a little-understood group
of dinosaurs, and distinguishes itself as the fourth non-avian theropod dinosaur
genus found with the remains of integumentary fibers -- all from the same region
of China.  Wow.

Quoting the first paragraph posted at <www.nature.com>:

"A therizinosauroid dinosaur with integumentary structures from China
Xing Xu, Zhi-Lu Tang, & Xiao-Lin Wang

Therizinosauroidea ('segnosaurs') are a little-known group of Asian dinosaurs 
with
an unusual combination of features that, until recently, obscured their
evolutionary relationships.  Suggested affinities include Ornithischia,
Sauropodomorpha, Theropoda, and Saurischia _sedis mutabilis_.  Here we describe 
a
new therizinosauroid from the Yixian formation (Early Cretaceous, Liaoning,
China).  This new taxon provides fresh evidence that therizinosauroids are 
nested
within the coelurosaurian theropods.  Our analysis suggests that several
specialized therizinosauroid characters, such as the Sauropodomorpha-like
tetradactyl pes, evolved independently within this group.  Most interestingly,
this new dinosaur has integumentary filaments as in _Sinosauropteryx_.  This
indicates that such feather-like structures may have a broad distribution among
non-avian theropods, and supports the hypothesis that the filamentous
integumentary structures may be homologous to the feathers of birds.

Dinosauria Owen 1842
Theropoda Marsh 1881
Coelurosauria _sensu_ Gauthier 1986
Therizinosauroidea Russell and Dong 1993
_Beipiaosaurus inexpectus_ gen. et sp. nov.

Etymology.  Beipiao: the city near the locality where the specimen was found;
saurus: lizard; inexpectus: referring to the surprising features in this animal.

Holotype. IVPP V11559 (Institute of Vertebrate Paleontology & Paleoanthropology,
Beijing, China; see Fig.1)."

End quote.  The reference is as follows:

XING XU et al: A therizinosauroid dinosaur with integumentary structures from
China
_Nature_ 399, 350-354 (1999) _Letters to Nature_

A character matrix and list for phylogenetic analyses is available on-line to
subscribers as a supplement to the paper.  (The paper is likewise available
on-line to subscribers at this time).  Being a subscriber myself (for the time
being), I don't know what of the above materials are available to 
non-subscribers.

Thank you all for keeping a lid on this, so the the legitimacy of the taxon is
secure.  Whew!

Question:  How should we pronounce the name of this fabulous animal?    ~:^\

Ralph W. Miller III <gbabcock@best.com>

(I hope that this doesn't mean you'll be too busy to discuss classroom 
"digestion"
activities)!