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Re: A couple of questions (Oviraptorids)



<... and an embryo included in one egg of Big Mama. To Citipati sp. is
assigned the "classic" skull and skeleton (GI 100/42) that was assigned,
for years, to Oviraptor philoceratops.>

  Actually, the egg and associated two troodontid skulls are not part of
"Big Momma", but rather a different, isolated find. The embryo was
referred to *Citipati* on the basis of a vertical premaxilla, but this is
questionable given the specimen's ontogenetic age. We have no idea the
premax variation that would occur, or the egg-shell variation among
oviraptorids that might predicate referral. It seems a good bet, but not
to *C.* sp..

<Note that I've just received the volume on the Proceedengs of the 5th 
Symposium of the Society of avian paleontology and evolution: in the paper
 "Oviraptorosaurs compared to birds" by Lu, Dong, Azuma, Barsbold and
Tomida 
> there is a description of a new specimen, PC 100/2112 (here labelled 
Ingenia sp.), that is almost identical to Citipati, particularly to GI 
100/42. When the paper was written, the Citipati description was not out
again, but for me this is another Citipati sp.>

  This skull is VERY like GI 100/42, with the exception of a *C.
osmolskae* dorsal profile of the skull and the problems of related the
crushed rear fourth of the skull. The quadrate seems more vertical, but I
can't say much else of it. Looks like *C.* sp. or whatever taxon GI 100/42
will be called. In particular, the sacrum is comprised of eight elements
and most of these compared to other maniraptorans appear to have been
added from the caudals.

  And before they jump on it, a big criticism. Lü et al., 2002, Maryanska
et al., 2001, and so forth, relate the oviraptorids to a clade within
Aves, particularly closer to modern birds than *Archaeopteryx* (and
dromaeosaurs are outside that clade), and rather close spatially to
confuciusornithids. This is an interesting conclusion, but it's fraught
with absence of data to round out the possibilities of placement. The
absence of segnosaurs and maybe a couple basal maniraptorans,
alvarezsaurs, and ornithomimosaurs, which in my own prelim studies really
do have an effect on the tree. If working from Czerkas and Martin's idea
of a non-dinosaurian Maniraptora, then at least several other
maniraptorans in the mix would have been influencial. The enormous about
of similarities in oviraptorids and some toothless early birds (e.g.,
Confuciusornithidae) avoids an essential problem of convergences, as basal
forms are less specialized. There are six-sacralled troodontids and
dromaeosaurids, some with braincase and postcranial features that far
surpass oviraptorids'. I have not seen the matrix, so I cannot really
comment on inclusiveness or character selection. If anyone out there could
offer this to me as I am not likely to get the paper for some time, it
would really be helpful of you and I would appreciate it greatly.

  On the topic of *Khaan*'s fingers, there are two basic finger
arrangements in maniraptorans: 1) the third finger is intermediate in
length between fingers one and two, and 2) the third finger approaches
finger two in length. Oviraptorids exhibit both types, where *Oviraptor*,
*Khaan*, *Conchoraptor*, *Chirostenotes*, and *Microvenator* have type 1;
*Citipati* is the only oviraptorid with type 2; *Ingenia* has shortened
second and third fingers, as does *Shuvuuia*, and *Caudipteryx* has a
shortened third finger with loss of the last two phalanges, and so the
manus type is unique for all three (types 3, 3 and 4, respectively). This
is true for all specimens with an articulated manus. Segnosaurs also have
a type 1 manus, and dromaeosaurids have a type 2; *Sinornithoides* has a
type 2, as well.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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