The holotype individual of the ornithopod dinosaur Leaellynasaura amicagraphica Rich & Rich, 1989 (late Early Cretaceous, Victoria, Australia)

Abstract

Doubt has been cast upon the association of the skull roof and postcranial bones, originally regarded as part of the same individual as the holotype, the left side of the skull, of Leaellynasaura amicagraphica Rich & Rich 1989. The reasons given for these doubts, the form of the prefrontal and the proportions of the supratemporal region being inconsistent with the holotype, are imprecise. The association is supported both by the morphology of the parietal and jugal, which are similar to those of Dryosaurus, and the unique sedimentological setting.

Key words:

• Cretaceous
• Dinosauria
• distortion
• high latitude
• holotype
• Leaellynasaura
• Ornithopoda
• taphonomy
• taxonomy

Acknowledgements

We wish to thank Nicholas van Klaveren, Natalie Schroeder and Helen Wilson for providing information about the circumstances under which the holotype individual of Leaellynasaura amicagraphica was collected. We also thank Draga Gelt, Steven Morton and Timothy Rich of Monash University and Martin Gomon of Museum Victoria for assistance with the graphics and Lesley Kool for preparation of the fossil. Thanks also for the long-term support by the Committee for Research and Exploration of the National Geographic Society, the Australian Research Council, and Atlas Copco for their support that made it possible to collect this fossil material. Finally, we thank Steve McLoughlin for his editing of this paper and Ralph Molnar, Kat Pawley, and Anthony Martin for their most helpful comments on the manuscript.