关键词: 云南省北部金沙江流域, 小兽, 恙螨, 群落结构

Abstract: Objective To study the structure of Chigger mite communities on small mammals in the surrounding areas of north Jinsha River in Yunnan.Methods The areas in different orientation surrounding north Jinsha River were selected as investigated spots.Small mammals were randomly captured with cage trap.Two auricles and hip of every small mammal host were chosen as a fixed site for collecting chigger mites.All the chigger mites on the surface of two auricles and hip were scraped off by a bistoury at first and then preserved in 70% of ethanol.Hoyer's medium was used to mount the chigger mites onto glass slides and every species of the specimens of the chigger mites on the slides was finally identified under a microscope.A series of ecological methods about community structure diversity and similarity was involved in this paper.Results The captured 302 small mammals were identified as 16 species and 13 genera in 7 families.4550 individuals of Chigger mites were collected from the two auricles of 302 small mammal hosts and they were identified as 63 species and 12 genera in 3 subfamilies of Trombioulidae.The amount of six dominant Chigger mites species accounted for 75.68% of the total mites,which were Walchia ewingi,W.micropelta,Leptotrombidium sinicum,L.scutellare,Helenicula simena,L.scutellare.There were 4 main species of small mammal hosts,which richness indices were above 10,the highest reached 32.While the diversity indices of the 4 hosts were above 1 with the highest index 2.5732.The similarity indices of community structure of Chigger mites on the same species of host in different ecological surroundings were all above 0.9.Conclusion The community structure of Chigger mite are complicated with high diversity index in the surrounding areas of north Jinsha River in Yunnan.