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Hamipterus, new pterosaur from Cretaceous of China found with eggs

From: Ben Creisler

Not yet mentioned yet on the DML. (I was able to download the pdf from
the link.)

Xiaolin Wangl, Alexander W.A. Kellner, Shunxing Jiang, Qiang Wang,
Yingxia Ma, Yahefujiang Paidoula, Xin Cheng, Taissa Rodrigues, Xi
Meng, Jialiang Zhang, Ning Li & Zhonghe Zhou (2014)Sexually Dimorphic
Tridimensionally Preserved Pterosaurs and Their Eggs from China.
Current Biology (advance online publication)
doi: http://dx.doi.org/10.1016/j.cub.2014.04.054

The pterosaur record is generally poor, with little information about
their populations, and pterosaur eggs are even rarer, with only four
isolated and flattened eggs found to date.

We report here a population of a new sexually dimorphic pterosaur
species (Hamipterus tianshanensis gen. et sp. nov.), with five
exceptionally well-preserved three-dimensional eggs, from the Early
Cretaceous deposit in northwestern China. About 40 male and female
individuals in total were recovered, but the actual number associated
might be in the hundreds. All of the discovered skulls have crests,
which exhibit two different morphologies in size, shape, and
robustness. The eggs show pliable depressions with cracking and
crazing on the outer surface. The eggshell, observed by scanning
electron microscopy and energy-dispersive spectroscopy, comprises a
thin calcareous external hard shell followed by a soft membrane.

These fossils shed new light on the reproductive strategy, ontogeny,
and behavior of pterosaurs. The cranial crests show sexually dimorphic
morphologies, with presumed males and females differing in crest size,
shape, and robustness. Ontogenetic variation is reflected mainly in
the expansion of the rostrum. The eggs have some external rigidity of
the general pliable eggshell, and the microstructure of the eggshell
is similar to that of some modern “soft” snake eggs. We suggest that
this new pterosaur nested in colonies and thus exhibited gregarious
behavior, a possible general trend for at least derived pterodactyloid

•A population of a new pterosaur was discovered with 40 male and
female individuals
•Sexually dimorphic morphologies differ in crest size, shape, and robustness
•Pliable eggs have a thin calcareous hard eggshell and a thick soft
membrane layer
•The expansion of the rostrum is an ontogenetic character for the new species

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