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> I was just wondering if anyone out there has seriously questioned the
> placement of _Monolophosaurus_ as basal Carnosauria. I feel like it is
> possibly basal Coelurosauria. I would be happy to discuss this with
> anyone, on or offlist, if there is any interest.
I'm not so sure it is basal Carnosauria. Before I go on I think it's
worth mentioning that "Carnosauria" means different things to
different people. As I understand the term, the "Carnosauria" is
a paraphyletic assemblage of non-coelurosaurian tetanurines
(megalosaurids, allosauroids, maybe spinosauroids). Others regard
the Carnosauria as a valid clade - the monophyletic sister-group to
the Coelurosauria (and the basal clade of the Avetheropoda) including
only the allosauroids and maybe a few closely related genera.
Confused? It gets worse. I believe the original description of
_Monololophosaurus_ regarded it as a "megalosaur-grade" theropod -
essentially a basal tetanurine or basal "carnosaur". But subsequent
revisions (sorry, don't have the papers handy) have moved
_Monolophosaurus_ further up the tree and put it somewhere among the
Allosauroidea. Under this scheme, the Allosauroidea is the sister-
group to the Coelurosauria.
The thing is, the line between derived "carnosaurs" and primitive
"coelurosaurs" is a little blurred. Look at the carnosaur-like
features of _Ornitholestes_ - Greg Paul (in _PDW_) even regarded
_Ornitholestes_ as an allosaurid. Future cladistic analyses could
push other "carnosaurs" - like _Baryonyx_, _Proceratosaurus_ and
_Gasosaurus_ - into the Coelurosauria.