Re: von Huene's Altispinax: a necessary clarification

["Jaime A. Headden" <qilongia@yahoo.com>]

Stephan Pickering (StephanPickering@cs.com) wrote:

<Thus: 
  Altispinax von Huene 1923 BMNH R1828 nomen conservandum
   = Becklespinax Olshevsky 1991 BMNH R1828 nomen rejectum
   = Valdoraptor Olshevsky 1991 BMNH 2559 nomen rejectum
   Altispinax lydekkerhueneorum Pickering 1990 BMNH R1828
    =   Megalosaurus oweni Lydekker 1889 BMNH 2559 nomen dubium
    = ?Acrocanthosaurus altispinax G.S. Paul 1988 nomen nudum
    = Becklespinax altispinax Olshevsky 1991 BMNH R1828 nomen rejectum et 
      nudum
    = Valdoraptor oweni Olshevsky 1991 BMNH 2559 nomen rejectum et nudum>

  Forgive me, especially for any crassness perceived, but it is my
understanding that only the ICZN can rule upon a _nomen conservandum_ or
_rejectum_ given these must be added to lists of names per said group. One
cannot just do this will-he/nill-he.

  The species *A. altispinax* for the same paradigm as the species *A.
lydekkerhueneorum* has precedent, and like it as not, would be the best
suited nomen given the twisted taxonomy. There is no further means of
comparison between the metatarsi made the paradigm of *Valdoraptor* or the
cranial dorsal vertebrae of *Becklespinax* to be compared to the first
named specimen, distinguished as George wrote _way_ back when, on a tooth.
George did not make the tooth the type of *Altispinax*, despite the
inappropriateness of the name.

  This would appear to me an attempted untwisting of thge history by
simply making all the specimens into a single paradigm, but there is no
way to easily confirm the associatiosn much less affinities of the
separate elements. In fact, comparisons of anatomy typically show the
different parts to pertain to different types of theropod:

  *Valdoraptor* has been likened unto the allosaurids, and it is under my
own comparisons that I cannot find any more suitable form to which they
woulkd apply. *Valdoraptor* may be a nomen dubium, but it is probably not
referrable to the same form as *Becklespinax*, a form whose vertebrae are
very different from those of allosaurids and tend to resemble, of
anything, spinosaurid (especially *Baryonyx* vertebrae) in the neural
arches (not spines) but with more "advanced" centra [reduction of
opisthocoely and cranial faces practically flat (=platycoelous) as in some
basal avetheropods]. The tooth is of generic identity, and *Altispinax*
can easily be considered a nomen dubium; basal theropod teeth are rather
conservative, unless you're a neoceratosaur it seems.


=====
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.

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