Hydrotherosaurus was a plesiosaur, a type of marine reptile. It was not a dinosaur, though it coexisted with many dinosaurs. The first Hydrotherosaurus fossil was discovered in 1943.

Quick facts about Hydrotherosaurus:

  • Existed from Maastrichtian Age to 66 million years ago
  • Lived in a marine habitat
  • Was a carnivore
  • Reproduced by live birth
  • Only one specimen has been found by paleontologists

All the Hydrotherosaurus illustrations below were collected from the internet. Enjoy and explore:

Hydrotherosaurus was described by the following scientific paper(s):
  • S. P. Welles. 1943. Elasmosaurid plesiosaurs with description of new material from California and Colorado. Memoirs of the University of California 13:125-254