HISTOLOGY OF DERMAL OSSIFICATIONS IN AN ANKYLOSAURIAN DINOSAUR FROM THE LATE CRETACEOUS OF ANTARCTICA

Authors

  • Armand de Ricqlès Université París, Laboratoire d' Anatomie Comparée. College de France, Paris.
  • Xabier Pereda Suberbiola Universidad del País Vasco/EHU, Departamento de Estratigrafía, Bilbao, Spain. Muséum National d'Histoire Naturelle, Laboratoire de Paléontologie, Paris.
  • Zulma Gasparini Museo de La Plata, Departamento de Paleontología de Vertebrados, La Plata.
  • Eduardo Olivero CADIC (Centro Austral de Investigaciones Científicas), Ushuaia.

Abstract

Ankylosaurian remains from the Late Cretaceous (Campanian) Santa Marta Formation of the James Ross Island in the Antarctic Peninsula include several types of armour, the most abundant being tiny, button-like ossicles (less than 5 mm in diameter). An histological study of these small ossicles evidences an original tissue structure. We notice the very small amount of vascularization and of bone remodeling. Some structural aspects strongly suggest a direct (metaplastic) mineralization of the preexisting stratum compactum of the dermis. However, some contradictory evidences support instead the hypothesis of the structures originating de novo at the limit of the stratum compactum and stratum spongiosum of the dermis and experiencing further growth via neoplasy.

KEY WORDS. Ankylosauria. Late Cretaceous. Antarctica. Dermal armour. Histology.

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Published

2015-10-01

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Thematic Volume