Abstract: This paper deals with the fatty acids in female midges of five species. They are Culicoides ebsoletus (Meigen), C. sinanoensis Tokunaga, C. nuiiangensis Liu,C. pulicaris (Linneaus) and C. punetatus (Meigen). The results showed that there were 12-14 major fatty acids in the female midges, of which the predominant ingredients were palmitoleic (C16:1), palmitic (Cl6:0), oleic (C18:1), and steraic(Cl8:0).Clustering analysis revealed that the Euclid distances between any two species of C.Obsoletus group was closer than that between C. obsoletus group and C. pulicarisgroup. The differences of the ingredients and contents among the five species are of some reference values to the taxonomy of Culicoides midges.

Key words: Culieoides obsoletus——Culicoides Pulicaris——fatty acid——gas chromatography