New fossil species of ommatids (Coleoptera: Archostemata) from the Middle Mesozoic of China illuminating the phylogeny of Ommatidae

摘要

BackgroundOmmatidae is arguably the “most ancestral” extant beetle family. Recent species of this group are only found in South America and Australia, but the fossil record reveals a much broader geographical distribution in the Mesozoic. Up to now, thirteen fossil genera with more than 100 species of ommatids have been described. However, the systematic relationships of the extant and extinct Ommatidae have remained obscure. Three constraint topologies were designed based on Kirejtshuk’s hypothesis, enforced the monophyly of Tetraphalerus + Odontomma, Pareuryomma + Notocupes and both respectively.