RE: turtle origins?

["ekaterina amalitzkaya" <eamalitz@hotmail.com>]

Is it that the sud afrikan paleotologist Broom was the first to propose a 
diapsid chelonia? I think Lee and Gaffney have proposed the best description 
of anapsid turtle hypothesis. The position of Lee is attractive in terms of 
the pareiasaur scute-carapace connection. But Hedges alternative of it being 
a derivative of the archosaurian armour is also good. But the question is do 
any cladistic analyses also lift any of the parareptiles such as 
nyctyphuretids, lanthanosuchids, captorhinomorphs or pareiasaurs lifted into 
diapsida/sauria? So what is the consensus on the temporal fenestra of the 
last common ancestor of the amniotes- was it anapsid? So this would this 
mean that the synapsids and the Diapsids evolved their fenestra 
independently. DOes this make sense? How good is the support of for a 
synapsid-diapsid clade to the exclusion of the diapsids? What about the 
millerosaurs how they behave in more modern analyses? And finally would 
Limnoscelis  be a sister group of all amniotes or nested within it.
_EA
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