Para- and polyphyletic dinos (was Re: Paraphyletic Dinosaurs...)

["Thomas R. Holtz, Jr." <th81@umail.umd.edu>]

At 03:26 PM 7/21/99 -0400, Jaime A. Headden wrote:
>You know, why we would have to coin a taxonomic unit
>to represent this or that paraphyletic group is beyond
>me when everyone could (and for the most part does)
>use vernacular terms, then this would be just as good.
>For instance, instead of calling 'em
>"Nontyrannosauria", one could just use
>"nontyrannosaurs;" it's simpler, more efficient, and
>one simply clarifiy definition before proceeding.

Exactly!!  Much as other biologists have been satisfied with doing
(non-human primates, for example).

[refering to "paleotheropods"]
>been used to denote very primitive theropods, which I
>guess would be things like *Procompsognathus*,
>*Segisaurus*, etc.

Sereno's 1999 review of dinosaur evolution in Science gives evidence that
_Procompy._ and _Segi._ are members of Coelophysidae and together form
Procompsognathinae, the sister taxon to Coelophysinae.

In a second posting, refering to prosauropods:
> and this would effectively exclude
>Plateosauria (a name that has been coined to my
>knowledge, correct me if I'm wrong)

There is indeed a formal taxon Plateosauria Tornier 1913, used by Sereno as
all decendants of the MRCA (most recent common ancestor) of _Plateosaurus_
and _Massospondylus_.

                        Thomas R. Holtz, Jr.
                        Vertebrate Paleontologist
Deptartment of Geology                  Director, Earth, Life & Time Program
University of Maryland                  College Park Scholars
College Park, MD  20742       
Webpage: http://www.geol.umd.edu        Phone:301-405-4084
Email:tholtz@geol.umd.edu               Fax:  301-314-9661