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Re: Fixing dinosaurian carnivour question




Tracy Ford - Ann & Randy wrote:

> >Also I would like to know if Quetzalcoatlus sp is ever going to be named!
> >Last I heard they were still debating over whether or not it was a juvenile
> >of Q.northropi or a seperate species.

The Qsp specimens don't appear to be juvenile.  Some of you guys know more about
species naming than I do, but I believe a different species name would have to
be based on skeletal differences in the wing between Qsp & Qn, and so far,
(insofar as I know) none have been identified that are not due simply to the
difference in size required to carry the additional loads (conceptually similar
to the skeletal differences between Morgan horses and Clydesdales).  I have the
Qsp left wing cast that appeared in Wellnhofer's book here at the house,
together with a cast of part of the northropi wing, and the only differences I
see are due to the required enlargements for muscle, tendon, and ligament
attachments and enlarged mechanisms for transferring shear and compressive loads
through the joints.

> I don't know if or when it'll be named, but it they are different genera.

If the above is based on the following statement, see response further below.

> >See the following for the skull of Quetzalcotalus...
> >Kellner, Alexander Wilhelm Armin, and Wang Langston, Jr., 1996. Cranial
> >remains of Quetzalcoatlus (Pterosauria, Azhdarchidae) from the Late
> >Cretaceous sediments of Big Bend National Park, Texas. Journal of Vertebrate
> >Paleontology, Volume 16, Number 2: 210-221.
>
> Different then the skull in Wellnhofer's book.

Langston's first name is Wann, not Wang.  The 'Qsp' beak in Wellnhofer's book is
an inadvertent mislabeling of a Tapejarid skull from much further down in the
Big Bend  formations (?Morrison from memory -- double check me on this because
I'm at the age where my memory has been known to blink out momentarily). The
Wellnhofer skull image did not belong to Qsp, and everyone involved is aware of
the unfortunate mislabeling (the mislabeled Wellnhofer photo was taken at UT
Austin, but was not one of the 10-11 Qsp specimens, and was not found in
association with them).  Also unfortunately and consequently, the chisel beak
has migrated from Wellnhofer's book and shown up in a lot of Qsp/Qn paintings
and illustrations.  The skull on Matt Smith's new Qn skeletal replica at the
Carnegie Museum corrects that error and is loosely based on Wann's recent Qsp
skull replica (so far, unpublished, and a work still in progress, but quite
lovely nonetheless), with Matt's Qn skull being about 2.06 times longer and with
height increased by a factor a bit more than that.  At the moment, there doesn't
appear to be evidence sufficient to demonstrate that Qn and Qsp are different
species or different genera. Would that there were.

JimC