Myosaurus

Myosaurus (Greek for “mice-like lizard,” with mys- meaning mouse, and -sauros meaning lizard) is a genus of dicynodont synapsids. Myosaurus was a small, herbivorous synapsid that existed around the early Triassic period. All of the fossils found of this species were found in Antarctica and South Africa. Compared to other fossils found from species that existed during this time, the Myosaurus is not common in the fossil record. This is due to a shortage of discovered fossils that possess characteristics unique to the Myosaurus. Notably, under 130 fossil fragments have been found that have been classified as Myosauridae, and almost all have been skulls. These skulls can be classified as Myosaurus because this species, unlike other dicynodonts, do not possess tusks or postfrontal teeth. The only species identified in the family Myosauridae is the Myosaurus gracilis, or M. gracilis. It should be recognized that the Myosaurus is almost always referred to as the M. gracilis in scientific research.

==History and discovery== The Myosaurus was first discovered in the Harrismith Commonage locality, a site found in the Lystrosaurus zone. This locality is based in South Africa. Around 10 skulls were discovered that could not be classified as Lystrosauridae, and were thus identified as being Myosaurus. Around 116 specimens later identified as Myosauridae were also found by W.R. Hammer and J. W. Cosgriff, and these specimens were located in the early Triassic Fremouw Formation of the Cumulus Hills in the Queen Maud Mountains. This location is found in the Transantarctic range in Antarctica. Almost all the specimens of Myosaurus found were preserved in green siltstone.