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Re: Regarding Hou's Mesozoic Birds of China



Nick Gardner wrote-

>     In his section on Liaoningornis, Hou describes the presence of two
> paired bones anterior to the sternum which he refers to as "presterna".
> >From the description, these sound more like the sternum had broken
anterior
> perhaps?  This looks plausible from the figures.

Yeah, the original description (Hou, 1997) mentions the fact the slab is
cracked and that the "presterna" may be only parts of the anterior sternum.
This is apparently what Hou now thinks, based on Zhou and Hou (2002).
Notably, the scapula is now identified as a possible pubis, and the coracoid
is thought to be in articulation with the sternum.  The pair of thin bones
extending from the coracoid to the distal humerus has been identified as the
other pubis.

>     This may or may not be directly related to Hou's paper, but I am under
> the impression that Sinornis was synonymized with Cathayornis. If this is
> true, which species was it synonymized with?  C. yandica? C. caudatus?  Is
> there a reference for this?  If they are synonyms, than why is there such
> variation in the amount of fusion present in the manus?  The mtcIII of
> Sinornis does not appear to be fused proximally to mtcII, but in C.
yandica,
> it is.  The caudals of C. caudatus _appear_ to not be fused distally into
a
> pygostyle.  Is this the correct condition or has the artist made a
mistake?

Sinornis was synonymized with (at least the holotype of) Cathayornis
yandica, the type species.  This was done officially by Sereno, Rao and Li
(2002) in the Mesozoic Birds volume.  "Cathayornis" caudatus was not
considered by Sereno et al. because they hadn't studied the material.  The
Sinornis holotype has a fragmented base to the carpometacarpus, and
metacarpal I is broken off in both manus.  Sinornis actually has all three
metacarpals fused to each other and the semilunate (but II and III are
separate distally).
Hou does describe "Cathayornis" caudatus as lacking a pygostyle, and while I
don't normally like to doubt descriptions of specimens without additional
evidence, only Hou has described Mesozoic pygostylians without pygostyles
(also some Confuciusornis, Longchengornis).  Hou also doesn't have the best
record for accurate interpretations.  I would say it was a juvenile
character, if not for Liaoxiornis.  Like most aspects of Hou's (1997) taxa,

>     Has anyone ran a cladistic analysis in which more than one species of
> Confuciusornis was included?  If so and it is published, can you provide a
> reference?  If it is not published and you if you wish to, could you
contact
> me offlist regarding it?

No, but look here- http://www.cmnh.org/dinoarch/2002Oct/msg00369.html
That's the most I've seen written on comparisons between Confuciusornis.

Mickey Mortimer