云南省保山等25县市黄胸鼠革螨的寄生状况

Primary Analysis of ectoparasitic gamasid mites on Apodemus chevrieri

目的初步了解黄胸鼠体表革螨在不同生境条件下的寄生状况、种类组成、优势螨种及其空间分布和性比特征以及革螨群落结构特点。方法选择云南省境内25个县（市）作为调查点，分别在四种不同的生境条件下用鼠笼加食饵诱捕黄胸鼠，用“全捕法”法采集其体表全部革螨。革螨群落结构用丰富度（S）、Shannon-Wiener多样性指数（H’）、均匀度（J’）及优势指数（C＇）描述。革螨空间分布格局用分布型指数中的扩散系数（C）、Cassie指数（CA）、丛生指数（1）及聚块指数（m^·／m）测定。结果在调查的25个县（市）中，共捕获到黄胸鼠3765只。3765只黄胸鼠体表采获到40种革螨，共计18251只，物种丰富度及生物多样性都很高（如S高达31，H’高达220．59）。毒厉螨，柏氏禽刺螨和纳氏厉螨三种革螨数量在整个革螨群落中占绝对优势，合计相对优势度Dr为93．58％，优势种地位突出，其余革螨相对优势度Dr只有6．43％。3种优势螨种在黄胸鼠体表的分布均表现为聚集型分布格局，其生活史时期均以雌成虫为主（25．66％～90．87％），幼虫比例最低（均小于1）。3种优势革螨的雌虫比例明显大于其相应的雄虫比例。结论黄胸鼠体表革螨种类繁多，群落结构复杂多样，毒厉螨，柏氏禽刺螨和纳氏厉螨3种优势螨种在宿主体表的寄生呈高度聚集性，雌性明显高于雄性。

To investigate the basic information of gamasid mites on the body surface of Apodemus chevrieri （a dominant species of wild rat in Yunnan, China） , including the mites species constitution and distribution, the dominant mites species and their spatial pattern, the sex ratio of the dominant mites species and the mites community structure, etc. Apodemus chevrieri （the host of mites） in 25 counties （towns） of Yunnan province was captured alive with mouse-traps. All the mite on the body surface of the hosts were completely collected. Richness, diversity index, evenness and dominance index were used to illustrate the community structure of gamasid mites on the hosts in the light of Shannon-Wiener＇s method. Disperse coefficient, Cassie index, clumping index and patch index were adopted to measure the spatial distribution pattern of gamasid mite. A total of 3 765 A. chevrleri were captured in 25 counties （towns）, and 40 species of gamasid mites （18251 individuals） were collected from the body surface of 3765 （chevrieri）. Both the richness and diversity index of gamasid mite community were quite high. Laelaps echidainus （Berlese, 1887） ,Ornithonyssus bacoti （Hirst, 1913） and Laelaps nuttalli （Hirst, 1915） were three dominant mites species with 93.58% of the total relative dominance, others with 6.43% of the total relative dominance. The three dominant mites species showed an aggregated pattern of spatial distribution among the diffcrent individuals of the small mammal host. More female adults were collected than the nymphs in the life history. The ratio of the female is much higher than that of the male in the three dominant mites species. From these obsecvations, it is concluded that the gamasid mites community on chevrieri is very abundant with more mites species. The dominant mites species on A. chevrieri are echidainus （Berlese, 1887）, Ornithonyssus bacoti （Hirst, 1913） and nuttalli （Hirst, 1915）. The distribution of the gamasid mite on chevrieri is of an aggregation pattern with more female adults.