Re: Antentonitirus pro-nun-see-a-shun?

["Mickey Mortimer" <Mickey_Mortimer111@msn.com>]

Jaime A. Headden wrote-

> <Actually, Antetonitrus would probably be thought of as a prosauropod
> using the traditional division between the two sauropodomorph groups.
> After all,
> > it is closest to Blikanosaurus and Lessemsaurus.>
>
>   Aside from *Lessemsaurus*, which was not mentioned by Yates and Kitching
> and its position in the analysis thus ambiguous, I beleive the
> relationship would be a traditional Melanorosauridae/Blikanasauridae
> relationship, which have been for a few decades considered close to the
> origin of sauropods more so than other "prosauropods."

To the contrary, Yates and Kitching do mention Lessemsaurus-
"Antetonitrus ingenipes most closely resembles Blikanasaurus cromptoni
(Galton & Van Heerden 1985) and Lessemsaurus sauropodoides (Bonaparte 1999),
both of which are poorly known (a partial hindlimb and a dorsal series,
respectively).  It differs from Blikanasaurus in having a less robust
metatarsus and lacking the marked cranial extension of the proximal
articular surface of metatarsal II. It differs from Lessemsaurus in having
triangular hyposphenes and incipient lamination of the dorsal neural
spines."
And melanorosaurids were thought to be closer to sauropods than Plateosaurus
only until the 1990's (or earlier).  Then with the advent of cladistic
analyses, the consensus for a decade was that they were actually part of a
monophyletic Prosauropoda and not particularily close to sauropods (eg.
Gauffre 1995; Galton 1990, 2001; Sereno 1989, 1997, 1998, 1999).  Now
opinions are turning around again, largely due to Yates' excellent work.

>   Or *Jingshanosaurus* with its fairly sauropod-like skull, or
> *Bellusaurus* with its sauropodan vertebrae and primitive leg
> structure....

Upchurch and Barrett (2001) found Bellusaurus to be a basal macronarian,
while Wilson (2002) could only say it was more derived than Barapasaurus and
more primitive sauropods.
I thought Jingshanosaurus was the Yunnanosaurus-like taxon, while
Yimenosaurus had the sauropod-like skull...

Mickey Mortimer