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Re: When did the comsognathid lineage end? (fwd)

Rutger Jansma (fam.jansma@worldonline.nl) wrote:

<And I suspect that Nquebasaurus is also soms sort of compsognathid based
on the overall similarities between it and Sinosauropteryx +
Compsognathus, like a relatively short arm when compared to the hindlimb.
Furthermore, the pubis is very similair to that of Sinosauropteryx and it
appears to have the characteristic "fan-shaped" dorsal neural arches for
this genus.>

  The fan-shaped neural arches have been questioned by some for both
*Compsognathus* and *Sinosauropteryx* based on defining the phrase, and
may actually be a basal coelurosaurian feature as they are present also
*Deltadromeus* for the caudal vertebrae, and could corresponded to
proximal ossification of the intraspinous tendons.

<And the unnamed Solnhofen genus, which, according to some sources, might
be a new species of Compsognathid. It only comprimises of a complete skull
and a few cervical vertebrae, more might be present though, given the
excellent preservation we have all come to love from this formation and
all I had to go on was a partial photograph.>

  Viohl mentioned this in issue 17 of the journal _Archaeopteryx_, and
theat partial photograph of the skull only and the few verts shows all
that there is.

<Scipionyx is another small theropod, and based on the pubic similarities
to Compsognathus, might also be a compsognathid, but it is based on a
juvenile specimen so many other distinctive characters are not present to
code for a detailed analysis.>

  In fact, all these taxa are fairly similar, and the so-called
compsognathid autapomorphies, some of which are seen in *Coelurus* and the
nearly complete skeleton of the "coelurid" that may geta  new name, may be
symplesiomorphies of a basal radiation of coelurosaurs.
  The youngest "compsognathid" appears to be from the Romualdo Member of
the Santana Formation, and is therefore Aptian in age.


Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)

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