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RE: Tyrannosaur stuff



Another interesting question in regards to this topic
is how long it took tyrannosauroids to become
"big-ass" after the end-Cenomanian extinction of
carcharodontosaurids/spinosaurids. Did the early Late
Cretaceous faunas (Turonian-Coniacian) in NA, for
example, contain any "big-ass" predators, and if so,
were they tyrannosauroids?? Perhaps there were some
"big-ass" Turonian dromaeosaurs?  :-)

Guy Leahy

--- Tim Williams <twilliams_alpha@hotmail.com> wrote:

> 
> T. Michael Keesey wrote:
> 
> >I'm not sure where the cut-off between
> "small-bodied" and "big-ass" is,
> 
> :-)   Let's go for an arbitrary cut-off of 4-5m. 
> Above that is 'big-ass".
> 
> >but _Alectrosaurus olseni_, _Alioramus remotus_,
> and _Dryptosaurus 
> >aquilunguis_ were smaller than any tyrannosaurines,
> 
> There is a school of thought that _Alioramus
> remotus_ is based on an 
> immature specimen, and so some of its
> 'autapomorphies' may be related to 
> ontogeny.  It could be a bona fide tyrannosaurine. 
> _Dryptosaurus 
> aquilunguis_ is estimated to be have been a little
> over 6m long, based on 
> the type material (which appears to come from an
> adult individual).  (The 
> type material for _Appalachiosaurus_ indicates an
> animal around the same 
> size as the _Dryptosaurus_ type specimen, but the
> former was immature when 
> it died.)  I'm not sure about the maxium dimensions
> of _Alectrosaurus 
> olseni_, given that the hypodigm for this species
> requires revision.  In any 
> case, all these guys were much larger than _Dilong_
> (1.6m; type) and 
> _Aviatyrannis_ (ilium only 90mm long) and
> significantly larger than 
> _Stokesosaurus_ and _Tanycolagreus_ (both maybe 4m
> in body length).  
> _Eotyrannus_, with an estimated body length of 4-5m,
> falls in the middle of 
> the "small-bodied" and "big-ass" categories.  :-)
> 
> >and not terribly larger than EK tyrannosauroids.
> 
> Some of the less well known theropod taxa from the
> EK may turn out to be 
> tyrannosauroids - like the rather large (but perhaps
> not "big-ass") 
> _"Chilantaisaurus" maortuensis_.
> 
> Cheers
> 
> Tim
> 
> 
>