RE: The Croc That Wanted to Be a Dinosaur

[Tim Williams <twilliams_alpha@hotmail.com>]

Jaime  Headden wrote:

> Alternate title, from M. Keesey: "Crocs: The Original Dinosaurs"

The amount of convergence between Triassic archosaurs and later dinosaurs is 
astonishing.  Not just _Shuvosaurus_ as an ornithomimosaur-mimic 
("ornithomimomimosaur"), but also tyrannosaur-mimics (_Postosuchus_), 
ornithischian-mimics (revueltosaurs) and probably ornithurine-mimics 
(_Protoavis_, or part of it).  We can probably throw aetosaurs in the mix as 
ankylosaur-mimics.  Now, if can only figure out what those 
pachcephalosaur-like domes from the Triassic of India really belong to...  
(Chatterjee originally touted them as evidence for Triassic 
pachycephalosaurs.)

As Mike Keesey noted, the forelimbs of_Effigia_ are extremely short.  Is 
_Effigia_ the first incontrovertible evidence for obligate bipedality in the 
Suchia?  I know the sphenosuchians include some gracile taxa that had an 
erect gait, but they were probably facultative bipeds at best (and I'm not 
sure if _Hallopus_ was a biped.)  Same for ornithosuchids.

>   It is also notable that many of tese features, as suggested by Nesbitt 
> and
> Norell, are found in various Chinle archosaurs, such as the 
> "chatterjeeids".

Nesbitt and Norell also suggest that the Argentine archosaur _Sillosuchus_ 
might belong to this group.

There is a family Chatterjeeidae Long and Murry, 1995.  So even if 
_Chatterjeea_ is a junior synonym of _Shuvosaurus_, then Chatterjeeidae 
remains as an available family name.

>   Note that not only is *Lagerpeton* included is a phylogeny testing the 
> early
> placement of various crurotarsans, but so is *Marasuchus* and both are
> dinosauromorphans. Technically, so is Pterosauria....

Darn... just as Dave Peters had convinced me that pterosaurs were lizards.  
:-)

>   Finally, Nesbitt and Norell note that this data provides evidence that 
> the
> cranial elements of *Shuvosaurus* belong to postcranial elements described 
> as
> *Chatterjeea*.

I don't want to tread on any corns... but I wonder how _Gojirasaurus_ fits 
into all of this, given its proposed chimeric nature.  Again, I don't have 
an opinion either way on this.

Cheers

Tim