Thaumatosaurus was a plesiosaur, a type of marine reptile. It was not a dinosaur, though it coexisted with many dinosaurs.

All these Thaumatosaurus pictures were collected from the internet. Enjoy and explore:

Thaumatosaurus was described by the following scientific paper(s):
  • J. A. Eudes-Deslongchamps. 1837. Mémoire sur le Poekilopleuron bucklandi, grande saurien fossile, intermédiare entre les crocodiles et les lézards, découvert dans les carrières de la Maladrerie, près Caen, au mois de juillet 1835 [Memoir on the Poekilopleuron bucklandi, a great fossil saurian, intermediate between crocodiles and lizards, discovered in the Maladrerie quarries, near Caen, in July 1835]. Mémoires de la Société Linnéenne Normandie 6:1-114
  • A. S. Woodward. 1895. Catalogue of the Fossil Fishes in the British Museum (Natural History), Part III