西藏林芝真蚋亚属三新种（双翅目：蚋科）

本文记述西藏林芝真蚋亚属Ｅｕｓｉｍｕｌｉｕｍ三种：凸端真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｃｏｎｃａｖｕｓｔｙｌｕｍｓｐ．ｎｏｖ．、林芝真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｌｉｎｇｚｉｅｎｓｅｓｐ．ｎｏｖ．、裂缘真蚋Ｓｉｍｕｌｉｕｍ（Ｅｕｓｉｍｕｌｉｕｍ）ｓｃｈｉｚｏｌｏｍｕｎｓｐ．ｎｏｖ 。

THREE NEW SPECIES OF EUSIMULIUM FROMLINGZHI ,TIBET ,CHINA (DIPTERA : SIMULIIDAE)

This paper deals with three new species of Eusimulium from Lingzhi ,Tibet ,China. Themale,pupa and larva of Simulium (Eusimulium) concavustylum sp. nov.;the pupa and larvaof S. (E.) lingzhiense sp. nov. ;the pupa and larva of S. (E.)schizolomum sp. nov. are respec-tively described and discussed. Three new species belong to the montium-group. Gill with 12filaments.Simulium (Eusimulium) concavustylum sp. nov. (Fig. 1)S. (E.)concavustylum sp. nov. is closely related to S. (E.) odontostylum Rubzov , 1947 ;S. (E.) shadini Rubzov, 1956 (from U. S. S. R.) and S. (E.) ghonmense Datta, 1975 (fromIndia) ,but is distinguished from S. (E.)odontostylum by cocoon with a well-developed mid-dorsal projection in this new species, and the style with apical tooth cluster in the latterspecies. This new species is readily differentiated from two other related species by the char-acteristic shape of the genitalia of male and the arrangement of the filament of pupa.Simulium (Eusimulium) Iingzhiense sp. nov. (Fig. 2)S. (E.) lingzhiense sp. nov. is closely related to S. (E.) ghoomense Datta, 1975 (fromIndia) ;S. (E.)chowi Takaoka , 1979 (from Taiwan);S. (E.) nomorivagum Datta ' 1973 (fromIndia);S. (E.) kobayashii Okamoto et al, 1958 (from Japan) and S. (E.) kirgisorum Rub-zov,1956 (from U. S. S. R.) ,but is distinguished from S. (E.) ghoomense and S. (E.)chowiby the cocoon without mid-dorsal projection in this new species. This new species is differentfrom three other related species by the second seginent of the antenna of larva with three an-nulets .Simulium (Eusimulium) schizolomum sp. nov. (Fig. 3)S. (E.) schizolomum sp. nov. is readily differentiated from all known other relatedspecies by the characteristic shape of cocoon i. e. this new species with one well-developedmid-dorsal projection,two lateral-dorsal projection and two or three windows on either side.