Titanosaur osteoderms from Upper Cretaceous of Argentina

[Ben Creisler <bcreisler@gmail.com>]

Ben Creisler
bcreisler@gmail.com

A new online paper:


Ignacio A. Cerda, Rodolfo A. García, Jaime E. Powell & Oscar Lopez (2015)
Morphology, microanatomy, and histology of titanosaur (Dinosauria,
Sauropoda) osteoderms from the Upper Cretaceous of Patagonia.
Journal of Vertebrate Paleontology (advance online publication)
DOI:10.1080/02724634.2014.905791
http://www.tandfonline.com/doi/full/10.1080/02724634.2014.905791#.VNCI4p3F_To



ABSTRACT—Titanosaurs are the only group of sauropodomorph dinosaurs
that possesses osteoderms. The Anacleto and Allen formations (Upper
Cretaceous) from northern Patagonia (Argentina) have provided an
abundance of these elements, isolated or associated with more or less
complete skeletons. Here, we study the morphology, microanatomy, and
histology of titanosaur osteoderms found in these stratigraphic units.
The size and gross anatomy of the osteoderms are strongly variable, as
well as their microanatomy, which ranges from compact structures to
those with strong development of cancellous bone. The primary bone
tissue is composed of structural fiber bundles that are ossified by
dermal metaplasia. Bone pathologies were identified in at least two
osteoderms. Bone histology suggests that the osteoderms were entirely
imbedded in the stratum compactum of the dermis. Titanosaur osteoderms
were probably employed for multiple functions, including mineral
storage and defense.