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Anhanguerid pterosaur skull variation and premaxillary crest shape



From: Ben Creisler
bcreisler@gmail.com

A new online paper:


R.A.M. Bantim, A.A.F. Saraiva & J.M. Sayão (2014)
Skull variation and the shape of the sagittal premaxillary crest in
anhanguerid pterosaurs (Pterosauria, Pterodactyloidea) from the
Araripe Basin, Northeast Brazil.
Historical Biology (advance online publication)
DOI:10.1080/08912963.2014.921818
http://www.tandfonline.com/doi/full/10.1080/08912963.2014.921818#.U4iivfldXTo


Sagittal cranial crests are evident in several groups of pterosaurs,
although their exact function has still not been determined. One of
the most distinctive features of the Anhangueridae is a sagittal
premaxillary crest on the anterior portion of the skull. A comparison
of the skulls of anhanguerids revealed that they all have similar
skull and crests shapes. In this paper, six anhanguerids from Araripe
Basin were analysed using bidimensional geometric morphometrics. As a
result, the taxa were arranged in two groups and two isolated taxa in
the morphospace: elongated skulls, with crests high and expanded,
representing 40% of the skull length; and median size skulls; and low
and short crests starting posteriorly on the region of the seventh and
fourth pairs of alveoli. Some of these groupings also share a
phylogenetic relationship. Despite this separation in morphospace, the
difference between the morphology of the crest was not as striking as
in other pterodactyloid pterosaurs. Crest variation in Anhangueridae
presented in this paper is considered as non-specific, with some
patterns of similarity, such as the shape and the beginning of this
structure on the premaxilla. In addition, the presence of positive
allometric growth in the skull was observed and no trend in sexual
dimorphism could be pointed.