RE: Choosing Twenty-Six Representative Genera

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Mike Taylor


Quite frankly your list could use MAJOR improvements.  I would suggest using
only forms for which good skeletons are known (or which are clearly
referrable to groups for which good skeletons are known).

This list is, sadly, a product of the sort of web-based environment we live
now.  People can pull up the "list of all dinosaur names" without any idea
if the taxon is based on more than a scrap (or for that matter, is even
formally published).  I'll through in a few comments.

>
> Dear Dino-Members,
>
> I come to you with a request for help.  I'm trying to put together a
> book overviewing the whole of the dinosauria for youngish children
> (maybe ages 7-9) by picking twenty-six representative genera -- one
> beginning with each letter of the alphabet.
>
> In selecting the genera, my goals, in decreasing order of importance,
> are as follows:
>
> 1.  Use each letter exactly once.
> 2.  Cover all the main branches of the dinosaurian "family tree".
> 3.  Use valid genera where possible (which I don't think it is for "F")
> 4.  Good (wide & even) coverage of geological time in which they lived.
> 5.  Good (wide & even) coverage of recent time in which they were named.
> 6.  I favour genera represented by good material where I have a choice.
>
> After _a lot_ of work, I have come up with the following list:
>
>       Argentinosaurus (Titanosauria)

Good

>       Borogovia (Troodontidae)

Very poorly known.  Byronosaurus, at least, has a partial skull known.  (I
would have gone with Brachiosaurus or Barosaurus or Baryonyx: something with
a resonable skeleton.

>       Chasmosaurus (Coronosauria)
>       Diplodocus (Diplodocimorpha)
>       Euoplocephalus (Ankylosauria)

The three above are excellent!

>       Futabasaurus (Tyrannosauroidea)

Completely, utterly useless.  Fukuiraptor would be your best bet for a valid
non-avian dinosaur with an "F"-name, but sadly it is very fragmentary.

>       Giganotosaurus (Allosauridae)
>       Harpymimus (Ornithomimosauria)

Guys are okay.

>       Irritator (Spinosauria)

Keep in mind that the published reconstruction of the skull is just plain
wrong: there will be some important changes when the revision is done (no
crest, for example).

>       Jobaria (Sauropoda)
>       Kentrosaurus (Stegosauria)
>       Lurdosaurus (Iguanodontia)
>       Massospondylus (Sauropodomorpha)

Above all good.

>       Nanshiungosaurus (Therizinosauria)

Unfortunately, not very well known.  None of the "N"-name dinosaurs are very
complete, though.

>       Oviraptor (Oviraptorosauria)
>       Parasaurolophus (Hadrosauridae)

Good choices.

>       Quetzacoatlus (Pterosauria)

Yeah, your kind of screwed with Q; Quaesitosaurus may be a junior synonym of
Nemegtosaurus.  Qantassaurus might serve, though.

>       Rahonavis (Avialae)
>       Sauroposeidon (Brachiosauridae)
>       Tyrannosaurus (Tyrannosauridae)
>       Udanoceratops (Ceratopsia)
>       Velociraptor (Deinonychosauria)

Good.

>       Wannanosaurus (Pachycephalosauria)
>       Xenotarsosaurus (Ceratosauria)

Best options you've got for these.

>       Yanchuanosaurus (Sinraptoridae)
>       Zephyrosaurus (Ornithopoda)

Good.

> It's worth making a few comments on this selection:
> 1.  Some choices -- e.g. Tyrannosaurus -- are clearly non-negotiable.
> 2.  Yes I know Quetzacoatlus is not a dinosaur!  It's too cool to omit.
> 3.  I believe that Futabasaurus is nomen nudum: are there any valid "F"s?
>
> Before I plough into writing a lot of prose on these genera, the
> families that they represent and their positions in them, I welcome
> anyone's comments on this selection.  Specifically, I would love to
> find a way to replace one of the somewhat redundant genera (the
> tyrannosaurid Futabasaurus or the sauropod Jobaria) with a
> Coelophysoid, Nodosaur or Centrosaurine -- can it be done, with
> appropriate reshuffling elsewhere?  Have I missed any other important
> groups?  Can I find anything geologically earlier than Massospondylus
> while keeping a prosauropod in the list?

Saturnalia and Plateosaurus would work; use Brachiosaurus for "B" and
replace Sauroposeidon with Saturnalia, for example.

> Are any of these genera likely to disappear in the immediate
> future (or have some of them already slipped out from under my feet?)

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
Fax (Geol):  301-314-9661       Fax (CPS-ELT): 301-405-0796