, 95:975 | Cite as

The skull of the giant predatory pliosaur Rhomaleosaurus cramptoni: implications for plesiosaur phylogenetics

  • Adam S. SmithEmail author
  • Gareth J. Dyke
Short Communication


The predatory pliosaurs were among the largest creatures ever to inhabit the oceans, some reaching gigantic proportions greater than 15 m in length. Fossils of this subclade of plesiosaurs are known from sediments all over the world, ranging in age from the Hettangian (approximately 198 Myr) to the Turonian (approximately 92 Myr). However, due to a lack of detailed studies and because only incomplete specimens are usually reported, pliosaur evolution remains poorly understood. In this paper, we describe the three dimensionally preserved skull of the giant Jurassic pliosaur Rhomaleosaurus cramptoni. The first phylogenetic analysis dedicated to in-group relationships of pliosaurs allows us to hypothesise a number of well-supported lineages that correlate with marine biogeography and the palaeoecology of these reptiles. Rhomaleosaurids comprised a short-lived and early diverging lineage within pliosaurs, whose open-water top-predator niche was filled by other pliosaur taxa by the mid-late Jurassic.


Reptiles Plesiosaurs Phylogenetics Anatomy Cladistics 



We thank N. Monaghan, M. Parkes and J. Sigwart (NMI) for supporting this project, S. Moore-Fay and C. Collins for the preparation, K. Grimes for photographs and R. O’Keefe, R. Schouten, R. Forrest and M. Taylor for the assistance. G. Mayr, M. Caldwell and three referees provided comments in review.

Supplementary material

114_2008_402_MOESM1_ESM.doc (155 kb)
ESM 1 (DOC 158 KB)
114_2008_402_MOESM2_ESM.xls (52 kb)
ESM 2 (XLS 53 KB)


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.School of Biology and Environmental ScienceUniversity College DublinDublin 4Republic of Ireland
  2. 2.Department of GeologyTrinity College DublinDublin 2Republic of Ireland

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