Re: Labrosaurus (was RE: birds and dinosaurs)

[Tim Williams <twilliams_alpha@hotmail.com>]

Mickey Mortimer wrote:

> Just which specimen of Allosaurus fragilis is the paratype?  YMP 1930 is 
> the
> holotype, USNM 4734 is the topotype, and DINO 2560 (=UUVP 6000) is the
> unecessary neotype...

The paratype for _A. fragilis_ is  USNM 4734 - which (by definition) comes 
from the same locality and horizon as the holotype.  USNM 4734 is a fairly 
complete specimen - unlike the holotype.  As a topotype, this specimen can 
be recruited to uphold the validity of _A. fragilis_.

USNM 4734 was collected in 1883 by M.P. Felch near Canon City, Colorado.  It 
is now exhibited at the USNM in D.C.  USNM 4734 must have been a rather 
unhappy individual when he/she died, given its misshapen lower jaw (from _L. 
ferox_), the broken shoulder blade, and the injury it sustained (and healed) 
in its belly region.

As Mickey notes, USNM 4734 would seem to make the designation of an _A. 
fragilis_ neotype redundant.  Further, DINO 2560 comes from a different 
locality to the holotype, and some authors (e.g., Bakker) think that USNM 
4734 and DINO 2560 represent different allosaur species.  It would be 
preferable (IMHO) that the name _A. fragilis_ be attached to a specimen from 
the _Allosaurus_ type locality.

To further muddy the waters, various new and unofficial _Allosaurus_ species 
have popped up in various sources (e.g., "Madsenius", "Allosaurus whitei", 
"Allosaurus jimmadseni").   "Allosaurus jimmadseni" appeared in a 
dissertation, and has yet to be officially named; "Madsenius" (like 
"Brontoraptor") may have emanated from the imagination of Bakker, and gone 
no further; and "A. whitei"... well that's a potential Pandora's box.  At 
any rate, all these names are currently _nomina nuda_, and it would be best 
if they were left out of scientific discourse until they are officially 
described.






Tim



Tim

_________________________________________________________________
FREE pop-up blocking with the new MSN Toolbar ? get it now! 
http://toolbar.msn.click-url.com/go/onm00200415ave/direct/01/