Systematic Taxonomy Of Platyscelidini From China(Coleoptera:Tenebrionidae)

The dissertation presents a systematic taxonomy of Platyscelidini from China on the basis of the examination of type and named specimens.The general part includes nomenclature and systematic status,history of studies,classification system,morphological characters,biology,material and methods,phylogeny,geographic distribution of Platyscelidini.The taxonomic part presents Chinese name and scientific name,bibliography,synonym and homonym,diagnostic characters,included taxa and distribution of each taxonomic unit,and also keys to tribe,genera(subgenera)and species from China.Data of type locality,type depository and studied material are provided for each species.Fifty-three plates with 419 figures are attached to show the characters of new species,parameres of male aedeagus,male protibiae,habitus,habitat and habit of Chinese species.The main results as follows:1.Taxonomic revision and new taxa.(1)Eighty-nine species within four genera are recognized from China(excluding species indeterminate),with 14197 specimens belonging to 88(99%)of the Chinese known species examined,of which 81(91%)being types.Twenty-eight new species are published,eight synonyms are ascertained,one subgenus and one species are newly recorded from China,two species are downgraded to subspecies rank(including unpublished one),lectotypes are designated for 22 species(including three unpublished ones).(2)The Nepalese Bioramix(Leipopleura)medvedevi Bai,Merkl & Ren,2019 was misidentified as the endemic Chinese species Bioramix(Leipopleura)politicollis(Kaszab,1940).2.Systematic status and phylogeny.Based on the concatenated dataset of three mitochondrial genes(COI,Cytb,16S)and one nuclear gene(28S),with 60 species within 4 genera of Platyscelidini as ingroup,the first molecular phylogeny of Platyscelidini is reconstructed.Bioramix,Myatis,Oodescelis and Platyscelis were recovered as monophyletic with strong supports.Myatis was recovered sister to Platyscelis,Myatis + Platyscelis was recovered sister to Bioramix,i.e.Oodescelis +((Myatis + Platyscelis)+ Bioramix).The monophyly of subgenera and phylogenetic relationships among them were not well demonstrated.3.Distribution pattern and origin.(1)The world fauna of Platyscelidini includes 215 species of eight genera,of which 213 inhabit Asia,only four species reaching Europe.Tajikistan has the highest diversity of genera,China has the largest diversity of species,the genus Bioramix has the widest distribution,subgenera Acutoodescelis and Planoodescelis are endemic to China.(2)In China,Xinjiang has the highest diversity of genera and subgenera,Xizang has the largest diversity of species,subgenera Acutoodescelis and Platyscelis has the widest distribution.Xizang and Qinghai are centers of diversity and/or origin of the subgenus Leipopleura,Sichuan is the center of diversity of the subgenus Cardiobioramix,Gansu is the center of diversity of the subgenus Platyscelis.It is predicted that new species of the subgenera Leipopleura and Cardiobioramix will be found in Xizang,Qinghai,and central China in the future,as well as new record species in Xinjiang.