Re: An Interesting URL!

["Mickey Mortimer" <Mickey_Mortimer11@msn.com>]

Christopher Robert Noto wrote-

> I'm curious what the current status of "Megalosaurs" are.  I know that
> some considered it a valid taxon, while others a vast wastebasket of
> unknown theropoda.  Is there any chance that "megalosaurs" are actually
> torvosaurids?

Depends on how broad your definition of "megalosaurs" is and who you ask.
Pretty much all taxa previously placed as megalosaurids are basal
tetanurines or carnosaurs, though there was the occasional ceratosaur and
coelurosaur threw in there as well. Current theories-
Sereno 1999
_________Afrovenator
|  |________Eustreptospondylus
|        |_____Torvosaurus
|        |_____Chilantaisaurus
|        |_____Spinosauridae
|__________Monolophosaurus
 |        |_____Sinraptoridae
 |        |_____Allosauridae
 |        |_____Carcharodontosauridae
 |__________Coelurosauria
Rauhut 2000
_________Piatnitzkysaurus
|_________"Szechuanosaurus" zigongensis
        |___________Magnosaurus (including Eustreptospondylus)
          |     |_______Monolophosaurus
          |     |_______Poekilopleuron
          |     |_______Torvosaurus
          |     |     |____Chilantaisaurus
          |     |        |___Spinosauridae
          |     |_______Afrovenator
          |          |_____Allosauridae
          |          |_____Sinraptoridae
          |          |_____Carcharodontosauridae
          |____________Coelurosauria
Holtz 2000
_________Spinosauridae
|_________Megalosaurus
 |_________Eustreptospondylus
  |_________Torvosaurus
   |_________Piatnitzkysaurus
    |_________Afrovenator
     |_________Monolophosaurus
      |       |_____Sinraptoridae
      |         |____Allosauridae
      |           |___Carcharodontosauridae
      |_________Coelurosauria
Edmarka rex is close to Torvosaurus, perhaps a junior synonym.
"Brontoraptor" is also similar to Torvosaurus, but seems more distinct.
Erectopus is a basal tetanurine according to Rauhut (2000).
New remains of Marshosaurus (Chure and Britt, 1997) suggest it is a basal
tetanurine closer to Megalosaurus and Eustreptospondylus than to
allosauroids.
Metriacanthosaurus coded identically to sinraptorids in Rauhut's (2000)
analysis, suggesting Paul's (1988) placement of the genus by
Yangchuanosaurus and the "Szechuanosaurus campi" skeleton was correct.
Valdoraptor seems to be a basal tetanurine.
Xuanhanosaurus came out as a basal tetanurine or carnosaur in Rauhut 2000.
Piveteausaurus is probably a basal tetanurine.
Becklespinax (=Altispinax?) has been said to be similar to Piatnitzkysaurus.
New remains show Gasosaurus to probably be a sinraptorid (Currie pers. comm.
to Holtz).
Kaijiangosaurus may be synonymous with Gasosaurus, but no one's looked at it
closely.
"Chilantaisaurus" maortuensis is a coelurosaur (Chure 1997, Rauhut 2000).
I think that covers the main taxa assigned to the Megalosauridae recently.
If you have questions about any of the lesser known taxa I didn't list, feel
free to ask.

Mickey Mortimer