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



Jaime Headden wrote-

>   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....

It's not that simple.  Nomingia has eleven dorsal vertebrae that are not
fused into the sacrum.  I said ten in my Details on... post, but after
reading Makovicky's thesis, it seems the "last cervical" of my post is the
first dorsal based on the large hypapophysis.  The tenth dorsal vertebra has
a transverse process that contacts the ilium though- does this make it a
sacral vertebra?  The eleventh dorsal centrum is sutured to the sacrum- does
this make it a sacral vertebra?  As usual, once we get to know situations in
detail, they reveal little complexities.  And what about Shuvuuia and
Avimimus?  They have seven sacral vertebrae too.

>   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 would agree the differences in caudal morphology may be due to
intraspecific variation, not incomplete preservation.  I don't recall you
giving me the idea the new Caudipteryx specimens are a new species, but it
would have been a while ago...  I'm still not certain we can assign C. dongi
to either C. zoui or C. sp. nov. with any assurance given the lack of good
cranial material.

Mickey Mortimer