Re: oviraptorosaurs (sensu lato)

["Jaime A. Headden" <qilongia@yahoo.com>]

Ken Kinman (kinman@hotmail.com) wrote:

<I will code it as such:
      8A   Therizinosauridae
      8B   Caudipteridae
     _a_   Oviraptoridae (incl. Caenagnathines)

I personally find splitting off caenagnathines (hope I spelled
this correctly) as a separate family unnecessary and a little
distracting (but you can split it into two small families if you
wish).>

  I would essentially agree with the idea that it might be more
simpler to render the taxon Caenagnathoidea to a single clade in
traditional trees instead of naming this group.... You'd be the
first to suggest a caenagnathine terminology.

<            3  Enigmosaurus
>               Erlikosaurus     (not sure how to
>               Nanshiungosaurus   code these genera)
>               Segnosaurus
>               Therizinosaurus>

  Based as they are on a few taxa with little overlapping parts,
the relationships are a little screwy without complete material.
Nonetheless, there are distinct individuals, but without
comparative distribution, that's as close as anyone's going to
get for now.

<    8B  Caudipteridae
            1  Microvenator
            2  Caudipteryx
            ?  {{Oviraptoridae}} "sedis mutabilis"
            3  Nomingia>

  I'd hesitate to place *Nomingia* anywhere without more
material; the tibia is reminiscent of both *Ingenia* and
*Chirostenotes*, and the pelvis is plesiomorphic to
Oviraptorosauria sensu stricto (inclusive of Caudipteridae).

<   _a_  Oviraptoridae
            1  Caenagnathasia
           2A  Chirostenotes
           2B  Elmisaurus
            3  Oviraptor
            4  Ingenia>

  I would change the latter two to 3A-B respectively. Suggestion
is that *Ingenia* could be intermediate in morphology between
caenagnaths and oviraptors....

<In any case, it is in such cases of cladistic uncertainty that
I believe paraphyly to be useful (but rendered
"semi-holophyletic" by adding the exgroup marker).>

  For now, I couldn't agree or dissagree. Too much work needs to
be done. There are projects on oviraptorosaur phylogeny and taxa
that should clarify at least the internal format of the
Oviraptoridae. I have my own opinions, too :) .

=====
Jaime A. Headden

  Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
  Where the Wind Comes Sweeping Down the Pampas!!!!

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