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Re: Dinosauricon Phylogeny: complete



Mickey Mortimer wrote:
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)


Heh, I thought I was losing my marbles for a second there... :-)

> What is _Jinzhouornis_?

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


Hm... perhaps in the near future someone will perform a specimen by specimen cladistic analysis of the Confuciusornithidae, or is that far too much to expect from anyone? Are the alleged account of hundreds of confuciusornithid specimens being recovered from the Yixian correct? How many are actually Confuciusornis?


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



Mickey Mortimer replied:
What's the source for this?


Eoenantiornis is restored with a single phalanx on the third manual digit in the paper describing it, I can't make much from the photographs. As usual though, I find the illustrations somewhat suspect, so I would like to know as well.




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).



Hm... I had just recently read Hou's book and was wondering about this myself. CMIIW, but doesn't the presence of more than 4 teeth still represent itself as possibly synapomorphic for Largirostrornis and Cuspirostrisornis?



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.


Can you provide a reference for the original description of Nanantius and "N. valifanovi", as well as for the synomization of Gobipteryx with "N. valifanovi"?



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.



Does this mean that the process identified in both Deinonychus and Archaeopteryx is homologous to those extensor processes? IIRC, such a process was described for the manus referred to Ornitholestes that is now referred to Coelurus, does anyone know about it?


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


Based on what characters did you get Otogornis as an enantiornithine? That reminds me of Hou 2000.



Nick Gardner

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