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David Marjanovic wrote-
>> 14. manual ungual II much smaller than
I
>> Another synapomorphy indicating Ingenia
the confuciusornithid sister group, not known in >> any other
theropod.
> Apart from Compsognathidae and Mononykinae at
least. :-)
Damn. I forgot about these, but I could come
up with a quantification that would exclude baryonychines and other basal
tetanurines.
Steve Brusatte wrote-
> Well, David, I don't know if this is exactly
what you are looking for, but Chiappe (2001)
> defined the clade in the Ostrom Symposium
volume. He diagnosed Pygostylia by using
> four synapomorphies: the loss of
hyposphene-hypantrum articulations in the thoracic
> vertebrae, the presence of a pygostyle (!),
the presence of a retroverted pubis forming an
> angle of 65-45 degrees from the main synsacral
axis, and the presence of a wide and
> bulbous medial condyle of the
tibiotarsus. He puts both the Confuciusornithidae and the
> Ornithothoraces (as sister groups) into the
clade.
His data matrix is a great resource for my analysis
btw.
But look at how weak the evidence
confuciusornithids are avians is- ;-)
1. no hyposphene-hypantrum
articulations
Also found in Mononykus.
2. pygostyle
As in the oviraptorosaur Nomingia.
3. opisthopubic pelvis
Like segnosaurs, mononykines, dromaeosaurids,
Bambiraptor and Sinornithosaurus.
4. wide and bulbous medial condyle of
tibiotarsus
As stated in Chiappe et al. (1999)- "The medial
condyle is slightly wider than the lateral one, a primitive condition shared by
other nonornithurine birds and nonavian theropods."
With these sorts of synapomorphies supporting avian
confuciusornithids, it should be easy to defend their oviraptorid position.
;-)
Mickey Mortimer
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