Comparative Morphology And Phylogeny Of Themus Motschulsky(Coleoptera:Cantharidae)from China

The thesis focuses on the systematics,comparative morphology and phylogeny of Themus Motschulsky,1858 from China.In the systematic account,it includes 3 subgenera 123 species of Themus.The subgenus Haplothemus has 57 species,of which 38 species are redescribed in detail;Telephorops has 16 species,of which 14 species are treated;Themus has 50 species,of which42 species are involved.Each subgenus is provided with the key to Chinese species.Each species is provided with the literature citation,type locality,type depository and distribution data.The redescribed species are provided with morphological description and examined material,also illustrated with the genitalia of both sexes and abdominal sternite VIII of female.In total,94 species are redescribed and presented with 616 illustrations.Among them,8 species are new to science,Themus(Haplothemus)bimaculaticollis Y.Yang et Su,2015,Themus(H.)centrostriatus sp.nov.,T.(H.)fissus Y.Yang et Kopetz,2016,T.(H.)imparipennis Y.Yang,2016,T.(H.)licentimimus Y.Yang et Su,2015,T.(H.)rectus Y.Yang et X.Yang,2015,T.(s.str.)dalatensis Kopetz et Y.Yang,2014,T.(s.str.)senensomimus Y.Yang et Kopetz,2014 and T.(s.str.)dimorphus Y.Yang et X.Yang,2015;3 species are recorded to China for the first time,T.(s.str.)minimus Kopetz,2010,T.(Telephorops)masatakai Okushima,2003 and T.(T.)cavipennis Champion,1926;T.(H.)mishiensis Wittmer,1973 stat.nov.is upgraded from the subspecies of T.(H.)elongatior Pic,1955;T.(s.str.)magnificus(Pic,1906)stat.rev.is resurrected from synonym of T.(s.str.)rugosocyaneus(Fairmaire,1889)and T.(H.)muganglingensis ?vihla,2004 stat.rev.is resurrected from synonym of T.(H.)parallelus Wittmer,1973.In the comparative morphological study,all the redescribed species are compared in the characters of head,pronotum,elytra,legs,genitalia of both sexes and abdominal sternite VIII of female.According to similarities and differences in these characters,some related species are classified into several species group.In the last part,based on the above results,a phylogenetic tree is established to analyze the relationships among the species of Themus.In the study,61 representative species of Themus are chosen as the inner group and 5 species of Cyrebion Fairmaire,Lycocerus Gorham and Stenothemus Bourgeois as the inner group.In total,84 morphological characters are selected and analyzed by both cladistic analysis programs Nona(Goloboff,1995)and Winclada(Nixon,1999–2002).As a result,it shows that all species of Cyrebion are grouped with the species of Themus,which suggests that the former may be a synonym of the latter.The species of the subgenus Haplothemus show close relationships,but not grouped into a single clade;the species of the subgenera Telephorops and Themus are mixed together.This result suggests that none of the three subgenera of Themus is supported as monophly,and the species could be classified into several species groups but subgenera,so that Haplothemus and Telephorops are also probably the junior synonyms of Themus.