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Tim Williams wrote-

> I would guess that David M. is referring to 'Pteromimus' and 
> 'Procoelosaurus'. Neither has been formally named or described. As such, it 
> is perhaps advisable to hold off on declarative statements regarding their 
> affinities until the material is published.

Also because the cladistic analysis in the thesis has the same problems as 
almost every analysis dealing with pterosaur affinities- Lepidosauromorpha is 
the outgroup, Prolacertiformes is an OTU, etc..  The latter fact means Peters' 
hypothesis is not tested.  It should be noted too that in that analysis, 
Ornithodira is only unequivocally supported by five characters (thin tapered 
fibula; advanced mesotarsal ankle; astragalus transversely widened; astragalar 
ascending process between tibia and fibula; calcaneal tuber absent (actually 
untrue in basal dinosaurs and dinosauromorphs).  Also, "Procoelosaurus" is only 
placed in Pterosauromorpha due to subthecodont dentition (pterosaurs aren't 
thecodont?) and a short ischium (which is found in reptiles primitively).  
"Pteromimus" is sister to Pterosauria because it has unserrated teeth (which is 
also primitive for reptiles, and  don't basal pterosaurs have serrated teeth?). 
 So their position as pterosauromorphs seems very poorly supported.  I'm not 
saying I agree they're langobardisaurs, but I would say I'm highly skeptical of 
Atanassov's placement.
Mickey Mortimer