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Re: Dinosauricon Phylogeny: complete



Nick Gardner wrote-

> Isn't the group with _Confuciusornis_ and _Changchengornis_ the
> Confuciusornithidae or the Confuciusornithiformes or something like that?

Yes, and it IS defined-
"The common ancestor of Confuciusornis sanctus and Changchengornis
hengdaoziensis plus all of this ancestor's descendants." (Chiappe et al.,
1999)

> What is _Jinzhouornis_?

A probable junior synonym of Confuciusornis.  See
http://www.cmnh.org/dinoarch/2002Oct/msg00369.html

> I'm confident that *Jibeinia* is outside Ornithothoraces. But
*Protopteryx*
> and *Longipteryx* could be Enantiornithes... my analysis has failed to
find
> them elsewhere.

But you didn't include several characters I used to place Longipteryx and
Protopteryx outside Ornithothoraces, so how could you test that hypothesis?
- maxillary fenestra present (P)
- postorbital contacts jugal (P)
- posteromedial sternal process absent (P)
- posteromedial sternal processes not pointed (L)
- broad posteromedian sternal process (P)
- scapula broad distally (L)
- interclavicular angle <58 degrees (P, L)

> *Eoenantiornis* could have 2 separate phalanges per 3rd finger, like *P.*,
> *L.* and *Eocathayornis*... which you forgot. :-)

What's the source for this?

> I'm confident that *Avisauridae* is real. I'm also confident that
> *Cuspirostrisornis** is either a member or a very close relative.
> *Concornis*, probably *Enantiornis* and apparently *Eoalulavis* are close
> relatives, too. *Sinornis* appears to be close, even though its rather big
> toe claws were not in my matrix.

I see that Cuspirostrisornis and Largirostrornis are together in an unnamed
clade in the tree, presumedly based on Hou's (2000) Cuspirostrisornithidae
containing the two genera.  Hou only supports this family by listing-
- relatively elongate snout.
Not true.  Both have snouts similar in length to Archaeopteryx,
Confuciusornis, Sinornis, the Spanish nestling, and other basal birds.
Neither are similar to Longipteryx or Yanornis in this regard.
- similar tooth count.
Supposedly 5-0-5 in Cuspirostrisornis and 6-?-6 in Largirostrornis.  Tooth
counts are notoriously difficult to determine accurately in Yixian birds,
Sinornis having 4-(>0)-(4-5) for instance.
- fused carpometacarpus
Pygostylian plesiomorphy.
- similar humerofemoral ratio
Cuspirostrisornis has one of 1.06, Largirostrornis 1.09.  Not different from
Iberomesornis (1.06), Liaoxiornis (1.06), or Eoenantiornis (1.11).
Sinornis' is only slightly higher (1.14).

> *Nanantius* is Ornithothoraces incertae sedis -- it could be a derived
> enantiornithine, or related to *Apsaravis*, or who knows.

Yes, the reason you (Mike) have it and Gobipteryx together is because of
Nanantius valifanovi, which is now a junior synonym of Gobipteryx minuta.
Nanantius is just a tibiotarsus which hasn't been looked at closely in the
recent past.

> *Yixianornis* has a few derived characters that *Yanornis* AFAIK lacks.
> Namely, it has a small extensor process on mc I, a shorter thumb, the tip
of
> its pygostyle appears to be upturned a bit, and the tip of its pmx is
> toothless; the latter 2 characters are not in my analysis.

Yanornis could have an upturned pygostyle, judging by the schematic
illustration in Zhou and Zhang (2001).  I'd be careful about the application
of the term "extensor process".  It seems to develop gradually from way back
in the Maniraptora.

> What synapomorphies do *Ambiortus* and *Otogornis* share? (I got the
latter
> as an enanti, despite its euornithine shoulder.)

According to Kurochkin (1999)-
- thickened, three-edged acrocoracoid with acute top.
- flat, wide humeral articular facet for scapula.
- ventral position of a small, short and oval humeral articular head.
- long and thin manual digit II-2.

Mickey Mortimer