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JON & ORNITHOLESTES
Jon Wagner has written us a long load of text on big
non-coelurosaurian theropods. And he says...
> I don't think anyone who talks about a monophlyetic
> Carnosauria thinks it includes tyrannosaurs, except maybe Norell and
What's your basis for this statement Jon?
Regarding Paul Sereno and the Allosauroidea, Jon writes..
> He has not, to my knowledge, given a definition of Allosauroidea, he's just
> labelled the
> node (IMHO, no priority for this sort of thing. Blind nodelabelling
> is kind of annoying).
You shouldn't have said this Jon - Sereno et al. (1996 - the paper
that describes the new _Carcharodontosaurus_ material
and _Deltadromeus_) does include a diagnosis of
Allosauroidea (in the notes and references section). One good derived
allosauroid character they cite, incidentally, is lack of nasal
participation in the antorbital fossa. And Jon - if you are
interested in the systematics and morphology of carnosaurs, you MUST
get hold of Harris (1998). It's one of the best theropod monographs
ever, up there with Currie and Zhao (1994) and Gilmore (1920).
Something Jon does not note is Phil Currie's endorsement of a
monophyletic Carnosauria. Though (to my knowledge), Currie has not
published an in-depth analysis of the relationships of these
theropods (yet), he has said that _Ceratosaurus_, sinraptorids and
allosaurids do belong together (which means he is at discordance with
the phylogeny in the Bakker, Williams and Currie _Nanotyrannus_
paper [where, if memory serves, acrocanthosaurs were basal
tyrannosauroids]... but then that was a long time ago).
>The thing is, the line between derived "carnosaurs" and primitive
>"coelurosaurs" is a little blurred. Look at the carnosaur-like
>features of _Ornitholestes_
_Ornitholestes_ is one of the most poorly known of 'well known'
theropods - Osborn's (1903, 1917) brief descriptions are inadequate,
as are the reappraisals of Ostrom (1980) and Paul (1988a, 1998b), and
Paul makes a few comments, and adds certain details in his
reconstructions, that are at odds with Osborn's reconstruction (e.g.
4 vs. 3 premax teeth). Goddam it, things are just a mess, with lots
of half-truths and rumours floating around in the literature - we
need a good monograph (and, of course, a number of theropod workers
are fully aware of this). But what _has_ been described and figured
so far is not carnosaur-like, so far as I can tell. (Well, Greg Paul
(1988b - PDOTW) did mention that the lower limb bones were 'short').
Got to go. They're closing the office.