Temnodontosaurus is a genus of ichthyosaurs in the family Temnodontosauridae. Fossils have been found mostly in Europe, but possibly in South America as well. It lived from the Hettangian to Toarcian ages of the early Jurassic period, from about 200 to 175 million years ago. Several species are known: the type species T. platyodon, T. crassimanus, T. eurycephalus, T. nuertingensis, T. trigonodon, and T. zetlandicus. Another species, Temnodontosaurus azerguensis, has been proposed by some paleontologists.