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Re: *Jeholornis* (Archaeopterygiformes: Rahonavidae)??



> > I think it's hardly similar at all. The dentary is long and low, instead
> > of very high and short as in oviraptorosaurs (even *Incisivosaurus*,
> > the least extreme example).
>
> Caenagnathids show a long and low dentary,

Sorry, I assumed their dentaries (not their whole lower jaws) were shorter.
False memory strikes again. :-) Unfortunately I can't find a caenagnathid
lower jaw in lateral view at the moment. -- But their symphysis is much
longer than that of *Jeholornis*, so it's still not similar... and I can't
find the famous caudal bifurcation of the dentary. Doesn't argue against it
being a very basal oviraptorosaur, but doesn't argue for it either.

> Second, a slender dentary is in line with the dentary observed in
> Archaeopteryx, impying it's connecting position between Archie and Ovi's.

In that case it's a plesiomorphy...

> > This <a reduced maxilla> sounds better. But it could be convergence
> > because of selection for a
> > strong bite in the front of the jaw...

Just trying to weight characters. :-) Devil's advocate is a well-paid job.

> > and it's also present in all
> > avebrevicaudans with described skulls.

Which might one day turn out as a synapomorphy of "enigmosaurs" +
Avebrevicauda... I have to get some numbers sometime.

> The distal end of the jugal is broken of about a centimer from the jugal
> process, so the curvature is not completely observed, but there is a small
> indication. The indicication is to be found just right of the quadrate
which
> is the remainder of the jugal of what is preserved. As you will notice,
> there is a curvature seen at it's distal end, a feature, as you have
> mentioned, is seen Incisivosaurus.

Looks like it.

> Meaning?

--+----+--*Archaeopteryx*
  |    `--+--*Rahonavis*
  |       `--*Jeholornis*
  |
  `--Avebrevicauda (and who knows what else)

> > > This has been my two cents...
> >
> > You're underpaid.
>
> Is this a compliment? ;)

Sure. Because you _got the idea_ of comparing it with oviraptorosaurs (and
did that in some detail), while the original describers apparently didn't,
there are none in their cladogram, and the text doesn't mention any.