A Taxonomic Study And Phylogenetic Research On The Tribe Leptochirini Of China (Coleoptera: Staphylinidae: Osoriinae)

Staphylinidae is one of the largest families in Coleoptera in Insecta. They occupy awide variety of habitats and feed on a wide range of food: besides most carnivorousspecies, there are also omnivorous, saprophagous, coprophagous, fungivorous,carpophagous and pollinophagous species. Staphylinidae has a close relationship withhuman and is an unneglectable resources. Some of them could be natural enemies ofverminous insects, and some could be used as medicinal materials while some arehygienic pests.Leptochirini is one tribe of the subfamily Osoriinae in the family Staphylinidae. Itwas established by Sharp in 1887. It includes 4 genera all together: Leptochirus,Borolinus, Priochirus and Thoracochirus. Up to the present, 368 species of the tribehave been known from the world. Among them 22 species have been known in China,of which 14 reported from the mainland of China, 11 from Taiwan, and 3 from boththem. Most species of the tribe are well adapted to habitats in leaf-litter layer and deadwood mainly in tropical zone.In China, however, taxonomic study on this genus is relatively behind. Up to thepresent, only some scholars separately studied on this field but no systematic worksconcerning Chinese Leptochirini. Most of the Chinese known species were described orrecorded by foreign scholars and the type specimens were deposited overseas. For thesereasons, it leaves us many difficulties to study the Chinese fauna of the tribeLeptochirini.This study was based on all related literature and examinations of about 380specimens collected from a lot of places in China. The results have been summarized asfollows:1. This paper was the first systematic study of the tribe Leptochirini of China.2. Within the paper, 21 Chinese species of the tribe were recognized. Among themthere were 9 new species and 5 species new to China including which were firstfound from Mainland.3. All the species were described in detail, with the research history, synonym,collecting data and distribution of each species. The color photos of all the specieswere given and the diagnostic characters were illustrated.4. The key to the Chinese species of the tribe Leptochirini was provided.5. A catalog of the 4 genera of the tribe Leptochirini in the world was edited. 6. A database of all the known species of the tribe Leptochirini in the world wasestablished.Besides, it is the first time that the phylogenetic relationship of the 4 genera of theLeptochirini was discussed through the cladistic analysis, with the WinClada software.It shows that Borolinus,Priochirus and Thoracochirus appear to be a monophyleticgroup, with common genealogic relationships. In addition, Leptochirus and the otherthree genera of the tribe, which are from one common ancestral progeny, demonstratethe sister group relationship between them.Abstracts of the New Species in This Paper1. Priochirus (Eutriacanthus) manfeiensis sp. nov. (PlateⅡ-C, Fig. 7)Body lengths: 13.2～14.0 mm (from front margin of head to anal end); 6.5～7.0 mm(from front margin of head to elytral apices).This new species is very similar to Priochirus alutaceus Bernhauer (1903), but canbe easily distinguished from the latter by the following points: median tooth of headshorter, with apex behind the level of the apices of lateral teeth; the sulcus in anteriorpart of vertex continuous.Holotype: (?), Manfei, Nabanhe Conv., Yunnan Prov., 9-Ⅰ-2004, LI & TANG leg.Paratypes: 4♀♀, same data as holotype; 1(?), Nabancum, Nabanhe Conv., Yunnan Prov.,26-Ⅶ-2005, LI & LI leg.2. Priochirus (Eutriacanthus) guangxiensis sp. nov. (PlateⅡ-D, Fig. 8)Body lengths: 8.6～10.0 mm (from front margin of head to anal end); 4.4～5.3 mm(from front margin of head to elytral apices).The present new species can be easily distinguished from all the known species ofthe subgenus Eutriacanthus by the particular shape of frontal teeth, by the differentforms of the male and female 9th sternite, and aedeagus.Holotype: (?), Leye Yachang Forest, Guangxi Chuang A. R., 26-Ⅶ-2004, YU &GAO leg. Paratypes: 3(?)(?), 5♀♀, Leye Yachang Forest, Guangxi Chuang A. R.,29-Ⅶ-2004, YU & GAO leg.