RE: pterosaur nostrils

["Thomas R. Holtz, Jr." <tholtz@geol.umd.edu>]

> From: owner-dinosaur@usc.edu [mailto:owner-dinosaur@usc.edu]On Behalf Of
> Daniel Bensen
>
> Where are they?  Pterosaur nares can be really big (in the large,
> later forms, specifically), and of course the actual holes
> through the skin can't be that big.  So where were the nostrils
> likely to be?  Toward the front?  The back?  The top? What's most likely?

Well, for one thing, the "nares" of later pterosaurs probably is an amalgam
of the nares proper and the antorbital/preorbital fenestra.  Thus the caudal
part of this opening probably housed the pneumatic tissues presumably
present in the antorbital fenestra.

Following the work of Witmer and colleagues, my first order approximation is
that the fleshy nostril would be at the rostral end of the opening, as it is
in nearly every other amniote they studied.  However, it must be added that
their justification in the case of various dinosaurs was the presence of
foramina and other bone traces associated with the soft tissues of the
fleshy nostril are at the rostral end of the snout: I do not know if Larry &
Co. have looked at pterosaurs yet for the same features.

                Thomas R. Holtz, Jr.
                Vertebrate Paleontologist
Department of Geology           Director, Earth, Life & Time Program
University of Maryland          College Park Scholars
                College Park, MD  20742
http://www.geol.umd.edu/~tholtz/tholtz.htm
http://www.geol.umd.edu/~jmerck/eltsite
Phone:  301-405-4084    Email:  tholtz@geol.umd.edu
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