Re: Suuwassea Press Release

[Mike Taylor <mike@indexdata.com>]

> Date: Wed, 12 May 2004 11:31:09 EDT
> From: Danvarner@aol.com
> 
> "Suuwassea is the first unequivocal new sauropod from the Morrison
> Formation a 150-million-year-old geological formation extending from
> New Mexico to Montana in more than a century."
> 
>        Seismosaurus gets no respect. It's the Rodney Dangerfield of
> sauropods. DV

Here's the full list of Late Jurassic sauropods from the U.S.A,
described since _Brachiosaurus_, _Haplocanthosaurus_ and 1903, and
still widely considered valid.  It's surprisingly short!

        1985: _Dystylosaurus_, _Supersaurus_
        1991: _Seismosaurus_
        1992: _Dyslocosaurus_
        1998: _Eobrontosaurus_

As you hinted, _Seismosaurus_ is rather cursorily synonimised with
_Diplodocus_ in Lucas and Heckert 2000.  The justifcation is
"... clearly not distinct from Diplodocus (B. Curtice, pers.  comm.,
2000)".  That's it.  Not entirely convincing yet, then.

Curtice et al. (2001) synonymise _Dystylosaurus_ with _Supersaurus_
I've not yet got that paper, but I'll be interested to see what it
says: that vertebra looks brachiosaurid to me.

_Supersaurus_ itself is trembling on the brink, having been
tentatively synonymised with _Barosaurus_ in a published abstract
(Curtice 2003).  He does get around, doesn't he?  Curtice seems to be
on a person crusade to eradicate _all_ Morrison dilodocids :-)  How
far will he go?

I mention _Dyslocosaurus_ because it has been claimed to be from the
Morrison, but also from the Lance.  I don't know if that controversy
is resolved yet, but at any rate _Dyslocosaurus_ can't be described as
an "unequivocal" Morrison sauropod.

That leaves _Eobrontosaurus_, which is Bakker's (1998) attempt to
revive everyone's favourite genus name using the _apatosaurine_
species _yahnahpini_ (Filla and Redman 1994).  I don't know of any
explicit slap-downs for the new genus, but it certainly doesn't seem
to be on everyone's lips.

So, to my surprise, it turns out that the claim in the press-release
is pretty much bang on target.  Although "unequivocal" is a cleverly
weaselly word to have used :-)


References
----------

Bakker, R. T.  1998. Dinosaur mid-life crisis: The Jurassic-Cretaceous
transition in Wyoming and Colorado; in proceedings volume for the "The
Lower to "Middle" Cretaceous terrestrial ecosystems" symposium,
Fruita, CO.  Spencer G. Lucas, James I. Kirkland and John W. Estep,
(eds.), Bulletin 14, New Mexico Museum of Natural History

Curtice, Brian D. and Kenneth L. Stadtman.  2001.  The demise of
_Dystylosaurus edwini_ and a revision of _Supersaurus vivianae_.
Western Association of Vertebrate Paleontologists and Mesa Southwest
Museum and Southwest Paleontologists Symposium, Bulletin, 8,
pp. 33-40.

Curtice, Brian D.  2003.  Two genera down, one to go?  The potential
synonomy[sic] of _Supersaurus_ with _Barosaurus_.  Southwest
Paleontological Symposium 2003, Guide to Presentations, Mesa Southwest
Museum, January 25 2003, unpaginated.

Filla, J. and P. D. Redman.  1994.  _Apatosaurus yahnahpin_: A
preliminary description of a new species of diplodocid dinosaur from
the Late Jurassic Morrison Formation of Southern Wyoming, the first
sauropod dinosaur found with a complete set of "belly" ribs.  Wyoming
Geological Assosiaction Guidebook 44:159-178

Lucas, S. G. and A. B. Heckert.  2000.  Jurassic dinosaurs in New
Mexico; pp. 43-46 in S. G. Lucas and A. B. Heckert (eds.), Dinosaurs
of New Mexico.  Bulletin 17, New Mexico Museum of Natural History and
Science.