Re: DML Omnipedia stuff

[Thomas_R_HOLTZ@umail.umd.edu (th81)]

>   Still doin' some work on the Omnipedia.  Here's some issues:
>
>   The clade Archosauria ("ruling lizards"?) includes the Crocodylia
>("???"), Pterosauria ("flying lizard"?), Dinosauria (including Aves),
>Thecodontia ("???") and ????

Thecodontia is paraphyletic.  Archosauria is DEFINED as all descendants of
the most recent common ancestor of birds and crocs.  All closer to birds are
Ornithosuchia, all closer to crocs are Pseudosuchia (aka Crurotarsi).
Pseudosuchia includes Ornithosuchidae, Aetosauria, Rauisuchidae,
Poposauridae, Parasuchia (aka Phytosauria), and the Crocodylomorpha.

>
>   Ornithodira ("bird ankle"?) includes Dinosauria, Pterosauria and ???
>
Ornithodira is a node within Ornithosuchia joining Dinosauria, Pterosauria,
and Lagosuchus.  The current phylogeny for this group seems to be:
 (Pterosauria + Schlermochlus ) + (Lagerpeton + ((Lagosuchus + Marasuchus) +
(Pseudolagosuchus + Dinosauria).

>   How's this definition:  Diapsida n. ("two holes in the head"?) clade of
>animals distinguished by two temporal fenestrae, consisting of the
>Archosauria and ?

ARchosauromorpha and Lepidosauromorpha.  Archosauromorpha includes
Archosauria, Prolacertilia, Rhynchosauria, maybe Choristodira.
Lepidosauromorpha includes Lepidosauria (squamates and tuataras), maybe the
Euryapsida, and some Permo-Triassic guys.

>Is there a feature that Saurischians share that they do not share with
>predentatans?  I've decided to drop Ornithischia in favor of Predentata and
>it might be a good idea to drop Saurischia for the same reasons.  What would
>be a good name?

Checklists of charcters shared uniquely between sauropodomorphs and
tehropods can be found in the Dinosauria and in Gauthier 1986. (Don't leave
home without these!)

>
>   I think I'm going to do a simple, static cladogram for the Omnipedia.
>Anybody have web pages with "up to date" cladograms I can put in links to?
>Also, in _The Dinosauria_, there's a clade between coelurosauria and
>maniraptora that is not identified.  It places the Elmisauridae in this
>clade.  Anybody know the name for this clade?
>
The name of the clade is "Out-of-date".  Elmisauridae is now within
Oviraptorosauria. Deinonychosauria is polyphyeltic.


Thomas R. Holtz, Jr.
Vertebrate Paleontologist
Dept. of Geology
University of Maryland
College Park, MD  20742
Email:Thomas_R_HOLTZ@umail.umd.edu (th81)
Fax: 301-314-9661
Phone:301-405-4084