New Pterodaustro Ref.

["Christopher Collinson" <Chris_Collinson@monarch.net>]

I don't believe this paper has been mentioned on list yet, so here goes.

Codorniú, L. and Chiappe, L. M. (2004) Early juvenile pterosaurs
(Pterodactyloidea: Pterodaustro guinazui) from the Lower Cretaceous of
central Argentina. Can. J. Earth Sci./Rev. Can. Sci. Terre 41(1): 9-18

Abstract:
 We report on two juvenile specimens of Pterodaustro guinazui, a
medium-sized, filter-feeding pterodactyloid pterosaur from the Lower
Cretaceous (Albian) lacustrine deposits of the Lagarcito Formation of
central Argentina (Sierra de Las Quijadas, San Luis Province). Both
specimens lack the skull, but one is otherwise nearly complete and
articulated, and the other is more fragmentary. Their small size (~300 mm of
wingspan), the lack of fusion of several postcranial bones, the minimal
epiphyseal ossification, and the porous appearance of the periosteal
surfaces indicate the specimens died at a very early stage of postnatal
development. The presence of derived characters unique, within
Pterodactyloidea, to P. guinazui (e.g., caudal vertebrae exceeding 16
elements) supports the proposed specific identification of the specimens.
The new material provides anatomical information previously unknown for P.
guinazui and sheds light on allometric transformations during the growth of
this pterosaur. Comparisons with more mature and much larger individuals
support two major allometric trends: (i) the negative allometric growth of
the proximal portion of the forelimb, and (ii) the positive allometric
growth of the metacarpal IV.

Cheers,
Christopher