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Re: Torvosaurus (or Megalosaurus) in Europe?



Jaime Headden wrote-

>   *Brachiosaurus atalaiensis* ----- *Brachiosaurus altithorax*

No, "Brachiosaurus" atalaiensis is not even titanosauriform as it lacks the
proximolateral femoral bulge (Salgado and Calvo, 1997).  Before someone
mentions Lourinhasaurus and Camarasaurus, the former was placed outside of
Neosauropoda by Upchurch and Barrett (2001).

>   Similarly, while smaller Morrison ornithischians are poorly known, there
> are several basal ornithischians in Portugal, including several
> thyreophroans, which do not presently compare well to Morrison material.

Poorly known?  Since when does Portugal have anything comparable in
completeness to Othnielia or Dryosaurus?  Which Portuguese thyreophorans
don't compare well with Morrison taxa?  Dacentrurus is the sister group to
Hesperosaurus in Carpenter et al. (2001).  Dracopelta is a small
non-ankylosaurid like Gargoyleosaurus and Mymoorapelta.  The
heterodontosaurid Echinodon has been reported from both Portugal and the US.

> teeth identified as tyrannosaur, velociraptorine, and *Ricardoestesia* [my
> copy of the Currie, Rigby, and Sloan paper (1990) makes no use of
> *Ric[h]ardoestesia,* oddly enough...]. Some remains from the Portugal
> levels are similar to the Kimmeridgian Solnhofen Limestone (cf.
> *Compsognathus*, teeth of *Archaeopteryx* sp.) and this is also
> contemporaneous with the lower Morrison.

I'd agree.  Of the Guimarota taxa, allosaurids, Stokesosaurus, basal
coelurosaur-like taxa ("Compsognathus" in Portugal, "Beelemodon" in the US),
troodontids, "velociraptorine-grade" eumaniraptorans and taxa close to Aves
(Archaeopteryx? in Portugal, "Paleopteryx" in the US) are also found in the
Morrison.  Richardoestesia and euronychodonts are so far absent from the
Morrison though.

>   The French have *Poekilopleuron*, a megalosaur that Greg Paul (1988)
> considers to be *Megalosaurus* as well, and there's the more generalized
> megalosaur *Edmarka rex* from the Morrison, and material that Bakker et
> al. have in prep that had a name, but remains to be described (making the
> name unavailable to use (so a warning: don't even try to use it here, it
> won't help)) of a more general nature that appears to be distinct. But,
> for the moment, the confusion of Morrison "megalosaurs" makes the
> identities of the material into different taxa ... questionable. We await
> study. Recent research by Holtz, Sereno and others indicates that
> *Torvosaurus* is closer to birds than is *Megalosaurus*, and in fact may
> be the sister group with spinosaurs.

The whole megalosaurid group is a mess.  Only Holtz has included
Megalosaurus in phylogenetic studies (1994, 1996, 2000), so saying "Recent
research by Holtz, Sereno and others indicates that Torvosaurus is closer to
birds than is Megalosaurus" is misleading.  Holtz didn't get a
Torvosaurus-Spinosauridae clade in those analyses either, so it's unknown if
Megalosaurus would join Torvosaurus in the almost universally accepted
Spinosauroidea.  If Tom is reading this, perhaps he'll elucidate where
Megalosaurus went in his 2001 analysis that did find a Spinosauroidea.
Poekilopleuron might not be a spinosauroid, as it didn't emerge in this
position in the only phylogenetic analysis it's been included in (Rauhut,
2000).  I do agree that the exact relationships of Torvosaurus, Edmarka and
"Brontoraptor" (ha ha ha :-) , it is useful to inform people what
"Brontoraptor" refers to, lest they see the name and not know what it is, or
think it's a dromaeosaurid *cringe*) are uncertain.  See
http://www.rjames.com/megalosaur/index.htm for a description of the material
that was to be named "Brontoraptor".

Mickey Mortimer