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Re: Old refs :-) [Really old....]



David Marjanovic (david.marjanovic@gmx.at) wrote:

<Zhou Zhonghe, Wang Xiaolin, Zhang Fucheng, Xu Xing: Important features of 
*Caudipteryx* --
evidence from two nearly complete new specimens, Vertebrata PalAsiatica = Gu 
Jizhui Dongwu Xuebao
38 (4), 241 -- 254 (October 2000)

Finally managed to copy this paper!>

  A paper which Mickey and I already discussed ... ;)

<But hey! *Nomingia* has _7 sacrals_, *Caudipteryx* only 5, that means, 
*Nomingia* has transformed
a caudal into a sacral, thus 22 of *Caudipteryx* is homologous to 21, not 22, 
of *Nomingia*!!!
This fits their shapes better and means that not 2 but _3_ caudals may be 
missing from the tail
end in IVPP V 123430!>

  Gosh, let's celebrate! It's a shear pity Nomingia couldn't have acquired 
excessive sacra from
the dorsal series, diagnostically short in maniraptorans, especially Oviraptor 
+ birds. The last
sacral is actually in the same position as the fifth sacral of most other 
five-sacral theropods
with relatively "normal" postacetabular alae. This is not counting the fact 
that two of the
anterior vertebrae in the pelvic block (not prepared) are clearly easily 
separated from the sacrum
in lateral view by a definite hiatus of matrix, but that they extend cranially 
beyond the
preacetabular alae. They appear to be dorsals, or at least one is a 
sacrodorsal. It works both
ways, David. I have also seen Mickey write about seven sacrals, and forgot to 
reply in that
degree. The only non-pygostylian maniraptoran with seven sacrals appears to be 
*Ingenia*,
sorry....

<On page 123 of Mesozoic Vertebrate life the tail end of NGMC 97-4-A, the type 
specimen of
*Caudipteryx zoui*, is drawn. It looks totally unlike that of IVPP V 123430 and 
is pointed, which
means that the latter specimen does NOT preserve the very end of the tail. The 
real end seems to
exhibit some fusion, but the drawing isn't very detailed, and the fossil itself 
isn't of much
better quality, as shown by the large areas of unpreserved bone.>

  After much fun discussion with Mickey, I introduced to him the idea that 
Caudipteryx sp. is a
new species, distinct from other specimens of Caudipteryx, but C. dongi is only 
just C. zoui in
disguise. Life's funny.

<Therefore I conclude _for now_: If Caudipter(yg)idae sensu Mortimer (onlist) 
is real,
*Caudipteryx* _may_ have fused its last 3 vertebrae into a pygostyle;>

  Yeah, now go to China and find it. Until then, the tail is a stiff rod 
without any apparent
fusion. Sorry for the coarseness, but this is the only real recourse for the 
suggestion, one
cannot work it out from photos and casts, or theory.

<the claim in the paper that "None of the caudals are fused, the pygostyle that 
was recently
reported in oviraptorids (Barsbold et al., 2000) is absent in *Caudipteryx* 
(Fig. 3; Pls. I -- II,
VI)" is apparently not based on the very end of the tail.>

  Yes, there may be more caudals apparent. Again, go to China.

<BPM 0001, referred to *C. zoui*, is the specimen a cast of which is now 
somewhere in the museum
here, which means I should sooner or later get a look at its complete tail end. 
Practically no
feather remains are preserved or at least prepared. So I was talking about its 
pubis when I
introduced the character "pubis gently concave over its entire cranial margin" 
into my matrix and
gave it to oviraptorosaurs including *Caudipteryx* but not *Avimimus*.>

  Good for you. Half right, anyway ... read below:

<But now I reread
 
Zhou Zhonghe, Wang Xiaolin: A new species of *Caudipteryx* from the Yixian 
Formation of Liaoning,
northeast China, same journal 38 (2), 111 -- 127 (April 2000)

Fig. 2, the reconstruction of the pelvis of IVPP V 12344 (holotype of 
*Caudipteryx dongi*), shows
a pubis intermediate between that of BPM 0001 and *Avimimus* (with an 
additional convex curve
shortly above the pubic boot). I can't say how accurate this is because the 
fused pubes are
preserved in caudal view which should make diagenetic compression able to 
produce this additional
curvature. If on the other hand this feature is real it may add evidence for 
putting *Avimimus*
among the oviraptorosaurs as was done in several SVP talks.>

  It would be interesting to some people to know that the "cranially concave 
pubis" character is
not as prevalent a feature in oviraptorosaurs as previously thought. In David's 
second cite, an
outline sketch of the pelvis of C. sp. was rendered, but until the first cite 
was published, it
was only a drawing. The pelvis drawn belongs to C. sp., and indicates that the 
pubes are actually
_sigmoid_ along their length. They do not just curve cranially from their iliac 
articulation, a
feature known only in Therizinosauridae and Ingenia. Other taxa, including 
Avimimus, Caudipteryx,
Nomingia, Chirostenotes and Triebold's new beastie, some oviraptorids, and 
Microvenator, have an
additional, plesiomorphic curve in the pelvis that reduces the cranial 
concavity to a cranial
sigmoidy. This destabilizes the utility of the character to an effective 
Therizinosauridae
autapomorphy. Now, dang, wish I could get that paper written so I can destroy 
all the other
oviraptorosaur and ovi/segnosaur synapomorphies, and show you what's really 
there.... Ah, as Enya
says, "Only time...."

=====
Jaime A. Headden

  Interesting Dichotomy:
  "When the state sends someone to the electric chair, it's called murder; when 
the state sends someone to prison, they sanction a gay dungeon."

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