RE: Titanoceratops, giant ceratopsian from New Mexico

[GUY LEAHY <xrciseguy@q.com>]

Here's a pic of the Oklahoma specimen:

http://en.wikipedia.org/wiki/Titanoceratops

Guy Leahy

----------------------------------------
> Date: Wed, 29 Dec 2010 14:33:39 -0500
> From: tholtz@geol.umd.edu
> To: bh480@scn.org
> CC: dinosaur@usc.edu
> Subject: Re: Titanoceratops, giant ceratopsian from New Mexico
>
> > From: Ben Creisler
> > bh480@scn.edu
> >
> > In case this new advance publication paper has not been
> > mentioned yet:
> >
> > Nicholas R. Longrich (2010)
> > Titanoceratops ouranous, a giant horned dinosaur from the
> > Late Campanian of New Mexico.
> > Cretaceous Research (advance online publication)
> > doi:10.1016/j.cretres.2010.12.007
> [snip}
>
> > At the end of the Cretaceous, 65.5 million years ago, the
> > giant ceratopsids Triceratops and Torosaurus dominated
> > North America's dinosaur fauna. The origins of these
> > giant ceratopsids, the Triceratopsini, are poorly
> > understood. This paper describes Titanoceratops ouranos,
> > a giant ceratopsid from the late Campanian (73-74 Ma) of
> > New Mexico, and the earliest known triceratopsin. The
> > holotype was previously interpreted as an aberrant and
> > exceptionally large specimen of Pentaceratops sternbergi,
> > but the animal does not show the diagnostic features of
> > Pentaceratops. Instead, cladistic analysis shows that
> > Titanoceratops is the sister taxon of a clade formed by
> > Eotriceratops, Triceratops, and Torosaurus. With an
> > estimated mass of 6.5 tons, Titanoceratops is the largest
> > dinosaur known from the Campanian of North America, and
> > rivaled Triceratops in size. The recognition of
> > Titanoceratops suggests that giant chasmosaurines evolved
> > once, among the Triceratopsini, and that the group
> > evolved large size five million years earlier than
> > previously thought. The giant horned dinosaurs probably
> > originated in the southern part of the North American
> > continent during the Campanian but only became widespread
> > during the Maastrichtian.
>
> The specimen in question is the tremendous Oklahoma Museum of Natural
> History skeleton labeled as (and frill restored after) Pentaceratops.
>
> Cool paper. But I disagree that this is the largest North American
> Campanian dinosaur: several hadrosaurids of this stage ("Lambeosaurus"
> laticaudus, Hypsibema, Parrosaurus, etc.) indicate HUGE duckbills.
>
> Interesting, though, that you get triceratopsin giants in the same region
> in which some awfully large robust tyrannosaurines were present...
>