pterosaur crest extensions

[David Peters <davidrpeters@earthlink.net>]

Was wondering if anyone on the list could answer this one:

In Pterorhynchus, Germanodactylus and Tapejara a number of workers have
shown that the premaxillary crest is extended dorsally by soft tissue,
but in Tupuxuara, Thalassodromeus, Dsungaripterus and Phobetoropter, to
name a few, no such extensions have been indicated.

Why not?

I'm wondering, if the soft tissue pattern holds, how big the crest of
Tupuxuara or Thalassodromeus _really_ was? or did the bony part
represent the fullest extent of it?

David Peters