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Re: Phylogeny of basal birds 1/3



David Marjanovic wrote-

> +--allzero outgroup
> `--+--*Caudipteryx* (no braincase characters included; pygostyle = ?)
>    `--+--Scansoriopterygidae (fusion of *S.* and *Epidendrosaurus*)
>       |--*Archaeopteryx*
>       |--basal Troodontidae (fusion of *Sinovenator* and *-ornithoides*)
>       `--+--*Microraptor* (because of the flange on manual phalanx II-1)
>          `--+--+--*Rahonavis*
>             |  `--*Shenzhouraptor*
>             `--+--*Hulsanpes*
>                `--+--*Yandangornis* (coded as lacking a pygostyle...)
>                   `--+--*Sapeornis*
>                      `--+--*Confuciusornis*
>                         `--polytomy of everything else

Looks good.

> Odontognathae has one synapomorphy: a reduction of the acromion.

Did you include Clarke's (2002) Carinatae synapomorphies?

1. ossified tendons bridging dorsal transverse processes.
Absent in Archaeopteryx, Confuciusornis, Patagopteryx, Baptornis and
Hesperornis.  Present in Ichthyornis and neornithines.
2. mid sacral vertebrae with dorsally projecting transverse processes.
Absent in Archaeopteryx, Confuciusornis, Chaoyangia, Sinornis, Patagopteryx,
Apsaravis, Baptornis and Hesperornis.  Present in Ichthyornis, Apatornis and
neornithines.
3. pneumatic foramen on dorsal midline of sternum.
Absent in Confuciusornis and Hesperornis.  Present in Ichthyornis and
neornithines.  I admit this could be related to the lowered pneumaticity of
diving hesperornithines.
4. lateral process on coracoid.
Absent in Archaeopteryx, Confuciusornis, Concornis, Neuquenornis,
Gobipteryx, Apsaravis, Baptornis and Hesperornis.  Present in Songlingornis,
Ambiortus, Ichthyornis, "Iaceornis" and neornithines.  The presence in
yanornithids (which were later placed outside Apsaravis + Ornithurae by
Clarke et al. 2002), complicates things.
5. no depression at the medial opening of the n. supracoracoideus foramen.
Absent in Archaeopteryx, Confuciusornis, Sinornis, Concornis, Neuquenornis,
Gobipteryx, Apsaravis, Baptornis and Hesperornis.  Present in Songlingornis,
Ichthyornis, "Iaceornis" and neornithines.  Similar statements regarding
yanornithids could be said here.

Mickey Mortimer