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



----- Original Message -----
From: "Jaime A. Headden" <qilongia@yahoo.com>
Sent: Thursday, November 01, 2001 6:59 PM


> 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 ... ;)

Yeah, sure. Of course. This is why I didn't write 10 or 20 KB about it as I
fear I'd have done otherwise, but just mentioned the issues that are most
important for me at the moment.

Shame on me that I really forgot that *C. dongi*, whatever it is, lacks a
skull, so of course I can't say it's distinct from IVPP V 123430 when the
authors don't do that either.

> <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

So you mean it has the normal 5 sacrals + 2 dorsosacrals, rather than the
normal 5 + a dorso- and a caudosacral? I wouldn't expect that, but of course
I don't know, so if it has the former condition, my paragraph cited above is
indeed rubbish. The shapes of the distal surfaces of the caudal centra would
fit, contrary to what I wrote, both conditions (*Nomingia*: 17 -- 20 flat,
21 and 22 rounded, 23 and 24 too small to make a meaningful distinction;
*Caudipteryx* sp.: 17, 18 and 21 flat, 20 in ventral view, 22 rounded) as
long as someone tells me what caudal 20 of *C.* sp. looks like in lateral
view.

> <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.

I don't have an opinion about whether *C. dongi* is *C. zoui* or not, and I
wrote so, I think. If my English is too long-winded and/or my sentences too
long, please tell me, I want to learn :-)

> <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.
> [...]
> Again, go to China.


I'd be surprised if I wouldn't wind up there sooner or later. Until then I'm
just a 19-year-old trying to defend the ? for character 26 of
*Caudipteryx*...

> Until then, the tail is a stiff rod without any apparent
> fusion.

So far we have statements from several people who saw and described the real
specimens that there is no fusion; statements from BANDits who may or may
not have seen the specimens that there is fusion (they took that as evidence
*C.* is a bird, just wondering what they say about *Nomingia*); the
low-resolution photo of the holotype in color photo 2E of Mesozoic
Vertebrate Life (between p. 110 and 111), which IMHO looks like the pointed
end might be a short pygostyle, but that's far from an argument; and the
drawing on p. 123 of same (Fig. 10.2D) that also looks suggestive of a short
pygostyle (but shorter than in *Nomingia*), but isn't very detailed and
shows large areas of unpreserved bone, as well as a line, behind the
distalmost such area, that doesn't reach the ventral margin -- which may be
indicative of partial fusion, something else entirely or just a mistake. The
accompanying text is silent. So for the moment I'll keep saying that we
don't know that *Caudipteryx* did not have a pygostyle.

> this is the only real recourse for the suggestion, one
> cannot work it out from photos and casts [...].

Depends on how good the photos and casts are IMHO (which is of course
untestable without the specimens at hand).

>   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.,

Sure? Not to IVPP V 12344 and thus *C. dongi*, as it seems to say in the
second cite?

> and indicates that the pubes are actually
> _sigmoid_ along their length.

Definitely not in BPM 0001, though.

> They do not just curve cranially from their iliac articulation, a
> feature known only in Therizinosauridae and Ingenia. Other taxa, including
[...]
> Nomingia,

Is the drawing in the Barsbold et al. 2000 Nature paper wrong/not
3-dimensional enough/...? I seem to have lost the URL for the Acta Pal. Pol.
paper.

> [...] 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....

Sounds interesting! Anyway thanks for telling me that therizinosaurids have
the feature, that eliminates a - from my matrix, even if a 1 must be changed
to a polymorphism! :-)