Technosaurus a silesaur? (from Bill Parker) (was Re: Krzyzanowskisaurus)

[Tim Williams <twilliams_alpha@hotmail.com>]

[Message forwarded on behalf of Bill Parker...- TW]

I don't subscribe to the DML but I do peruse the archives.  In case no one
has answered, here you go.  Feel free to post this response to the DML.

Tim Williams wrote:

> Very true. But what I was alluding to is that, given that _Revueltosaurus_
> and_Silesaurus_ are both herbivorous non-dinosaurian archosaurs from the
> Late Triassic, it is possible that superficially ornithischian-like teeth
> could come from 'silesaurs', as well as 'revueltosaurs'.

We (Randall Irmis, Sterling Nesbitt and I) have tentatively argued that
Technosaurus may represent a 'silesaur' based on the morphology of the
premaxilla that was excluded from the holotype by Sereno.  I scaled the
holotype material over the reconstruction of the skull of Silesaurus and
the premax and dentary fit well so Sereno's removal of the premaxilla from
the type based on size is unwarranted.  Presumably they were also divided
as the premax seemed to superficially resemble a sauropodomorph whereas the
dentary was considered to be ornithischian. Interestingly a
'sauropodomorph'-like premaxilla combined with an 'ornithischian' like
dentary is found in one taxon...Silesaurus.  BTW...according to Sterling
Nesbitt the posterior jaw fragment of Technosaurus belongs to Shuvosaurus
(found in the same quarry).

************************************************************************
Bill Parker
Vertebrate Paleontologist
Division of Resource Management
Petrified Forest National Park
P.O. Box 2217
1 Park Road
Petrified Forest, AZ 86028
(928) 524-6228 x262