Re: Segnosauria vs. Therizinosauria

[Dinogeorge@aol.com]

In a message dated 4/6/00 4:04:48 PM EST, twilliams_alpha@hotmail.com writes:

<< It may come to be that the teeth named _Troodon_ are not diagnostic at the 
genus/species level (as happened for _Deinodon_ and _Trachodon_).  If so, it 
too gets flung into the abyss as a _nomen dubium_.  This possibility has been 
raised a few times (and I think once in a paper by Tom Holtz - apologies if 
I'm mis-quoting; I'm going from memory).  Should this occur, we go back to 
calling this family the Saurornithoididae.  _Saurornithoides_ is based upon a 
reasonable specimen.  _Troodon_ isn't.  My point is that it might have been 
easier back in the 1980's to retain the name Saurornithoididae for this 
family, irrespective of the "new" _Troodon_ material that was being described 
at the time. >>

I wouldn't be at all surprised if  Troodon is soon declared a nomen dubium. 
Then Troodontidae would be replaced by the next oldest family-level taxon, 
which is indeed Saurornithoididae. There is, however, a peculiarity that may 
develop. If the genus Ornithodesmus, which is now known to be a small 
theropod, proves to be a troodontid, then its family name Ornithodesmidae 
Hooley, 1913 takes precedence over >both< Troodontidae Gilmore, 1924 (coined 
when Troodon was thought to be a pachycephalosaur, senior synonym of 
Stegoceras) and Saurornithoididae Barsbold, 1974.