Mixosauridae was an early group of ichthyosaurs, living between 247.2 and 235 million years ago, during the Triassic period. Fossils of mixosaurs have been found across the Northern Hemisphere (Europe, Asia and North America).
Mixosauridae was an early group of ichthyosaurs, living between 247.2 and 235 million years ago, during the Triassic period. Fossils of mixosaurs have been found across the Northern Hemisphere (Europe, Asia and North America).
==History and classification== ===Naming and definitions=== Mixosauridae was named by Georg Baur in 1887 as a family-level group to contain the new genus, Mixosaurus that he named in the same publication. The name Mixosauria has been used for a larger group containing Mixosauridae, but also as an equivalent term for Mixosauridae, resulting in Mixosauria being regarded as a junior synonym of Mixosauridae. Motani defined the clade Mixosauria as comprising all descendants of the last common ancestor of Mixosaurus cornalianus and M. nordenskioeldii, which was applied to its equivalent group Mixosauridae by Maisch and Matzke in 2000. This definition was emended by Ji and colleagues in 2016 by replacing Mixosaurus nordenskioeldii with Phalarodon fraasi, as the former had since been determined to not be diagnostic. The definition was changed again in 2017, this time by Moon. As the evolutionary relationships his analyses found would have resulted in many traditional mixosaurids falling outside of the group, he redefined it as being all ichthyosaurs more closely related to Mixosaurus cornalianus than Ichthyosaurus communis for consistency.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).