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Sharovipteryx & pterosaur ankles

I don't think Sereno's 1991 paper (on basal archosaurs) even mentions Sharovipteryx or the prolacertiforms, so perhaps he believes the similarities between Sharovipteryx and pterosaurs to be convergences (not sure).
But I would assume that those workers who ally pterosaurs to the prolacertiforms must believe that the derived ankle-type of pterosaurs is convergent with the similar ankle of dinosauromorphs (contra Sereno's view that such ankles are synapomorphic). Does Sharovipteryx have this same ankle type or something more primitive?
-----------Cheers, Ken Kinman
P.S. I don't think Dinosauricon shows either _Doswellia_ or _Elastichosuchus_. Doswellia was described by Weems, 1980 (Transactions of the American Philosophical Society, 70(7):1-53). Elastichosuchus was described much earlier (I think it is listed in Romer, 1966).
******************************************************* 
From: "T. Mike Keesey" <tmk@dinosauricon.com>
To: Ken Kinman <kinman@hotmail.com>
CC: dinosaur@usc.edu
Subject: Re: Sharovipteryx
Date: Tue, 23 May 2000 14:01:50 -0400 (EDT)

On Tue, 23 May 2000, Ken Kinman wrote:

>      I would be interested to know if you regard Sharovipteryx as a
> prolacertiform or as an archosauriform (perhaps an ornithodiran, sensu
> stricto).

My observation is that people tend to place _Sharovipteryx_ wherever they
place Pterosauria. If they conside pterosaurs to be prolacertiforms, _S._
goes there. If they consider them to be ornithosuchians (not to be
confused with ornithosuchIDs), _S._ goes there.

The same can not be said for the other pterosaur sister-group candidate,
_Scleromochlus_, which always seems to be placed in Ornithosuchia.

These are just observations of existing phylogenies.

> The same question could be asked concerning Longisquama. In the
> archosauromorph classification I posted yesterday, I preliminarily placed
> them both as prolacertiforms, but I'm certainly not strongly wed to this
> position.

On my site I keep _L._ as ?Archosauromorpha _incertae sedis_.

> I'm even more uncertain about Doswelliidae.

Dos-who-iidae?

-- T. Michael Keesey .................................. <tmk@dinosauricon.com>
My Worlds (including The Dinosauricon) ... <http://dinosauricon.com/keesey>
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