title: New fossil species of ommatids (Coleoptera: Archostemata) from the Middle Mesozoic of China illuminating the phylogeny of Ommatidae.
abstract: BACKGROUND
  Ommatidae 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.
  
  
  RESULTS
  In this study, four new species, Pareuryomma ancistrodonta sp. nov., Pareuryomma cardiobasis sp. nov., Omma delicata sp. nov., and Tetraphalerus decorosus sp. nov., are described. Based on well-preserved fossil specimens and previously published data the phylogenetic relationships of extant and extinct lineages of Ommatidae were analyzed for the first time cladistically. Based on the results we propose a new classification with six tribes of Ommatidae: Pronotocupedini, Notocupedini, Lithocupedini, Brochocoleini, Ommatini and Tetraphalerini. These taxa replace the traditional four subfamilies.
  
  
  CONCLUSIONS
  There is good support for the monophyly of the ingroup. Notocupedini, as defined by Ponomarenko, are paraphyletic. Notocupoides + Eurydictyon are the sister group of the remaining fossil and extant ommatids. Together they form the clade Pronotocupedini. Notocupedini and Lithocupedini are the next two branches. The tribe Brochocoleini is the sister group of a clade comprising Tetraphalerini and Ommatini.
authors: Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Box 92 No. 1, Beichen West Road, Chaoyang District, Beijing 100101, People's Republic of China.
authors: Jingjing
authors: J
authors: Tan
authors: Yongjie
authors: Y
authors: Wang
authors: Dong
authors: D
authors: Ren
authors: Xingke
authors: X
authors: Yang
mesh_terms: D000818:Animals; D002681:China; D001517:Coleoptera / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics*; D005580:Fossils; D010802:Phylogeny; D009626:Terminology as Topic