Wikipedia
Mixosauria
The Mixosauria were an early group of ichthyosaurs, living between 250 and 230 million years ago, during the Triassic period. Fossils of mixosaurs have been found all over the world: China, Timor, Indonesia, Italy, Germany, Spitsbergen, Switzerland, Svalbard, Canada, Alaska, and Nevada.
Cladogram based on Motani (1999), Maisch and Matzke (2000), and Jiang, Schmitz, Hao & Sun (2006), with clade and generic names following Maisch (2010):