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Re: New Jeholornis specimen



David Marjanovic wrote-

> Wonderful. Wonderful... just right now, right today, while I'm coding that
> animal for my analysis of K birds. Aaaah... and extra info on *Sapeornis*,
> too. It's so great :-)

Yeah, I was able to add several codings for Jeholornis too.  And good
sternal information just as I'm coding that area.  I'm on character 180- the
length/width ratio of the sternum.

> > They confirm the absence of premaxillary and maxillary teeth, but one
> > has a couple dentary teeth.
>
> While *Shenzhouraptor* is said to have premaxillary teeth, right?

No, Shenzhouraptor is said to lack visible dentition.  But the dentary teeth
of Jeholornis seem hard to discern, so that (and the absence of upper
dentition on any of these specimens) may not mean much.
Incidentally, Shenzhouraptor was reported to have 23-25 (and possibly more)
caudal vertebrae, which should have been a hint some of Jeholornis' holotype
were missing.

> And can someone tell me if the articulation between scapula and coracoid
> is as in Enantiornithes (peg on the coracoid in a socket in the scapula)
> or in Euornithes (peg on the scapula in a socket in the coracoid)?
> (*Rahonavis*, *Longipteryx* and *Eocathayornis* have the enantiornithine
> condition.) While I am at it, can someone confirm the euornithine
> condition in *Otogornis*, and tell me which one *Jibeinia* and
> *Protopteryx* have?

Impossible to tell the condition in Jeholornis from the scapula in lateral
view, and the coracoid in anterior/ventral view.  I also cannot determine
the condition in Otogornis, and that of Jibeinia is undescribed (and
probably not preserved).  Protopteryx has a flat articulation for the
coracoid on the scapula, so is intermediate between the enantiornithine (and
apparently basal) condition and the ornithuromorph one.

> > The hallux is reversed as preserved.
>
> Hm... it's pretty long, but mt I is located as high up on mt II as in
> Archie, and the claw of I points the same way as the others...

True, at least for one pes of the less complete specimen.  I really should
have checked this before I repeated the author's statements.

> While I am at it, what should I choose as an outgroup for an analysis of
> the above problem, without having to make a 500-character coelurosaur
> analysis out of it?

Why not make a Denonychosauria outgroup by independently coding several
deinonychosaurs, then making PAUP treat them as a forcibly monophyletic
outgroup?

Mickey Mortimer