云南大理洱海周边地带小兽体表恙螨群落相似性及分类研究

目的 探讨云南大理洱海周边地带12种主要小兽体表恙螨群落之间的相似性及移行规律。方法 在云南大理洱海周边地带野外选点，于不同生境下诱捕小兽。对小兽及其体表的恙螨种类进行分类鉴定。应用系统聚类分析方法，计算Block距离。组内连接法（within-group linkage）进行聚类，聚类结果用树状图（dendrogram）表达。结果 齐氏姬鼠、灰麝鼩、锡金小鼠、斯氏家鼠和大绒鼠体表恙螨群落之间相似性较大，聚为一类，基本属于野柄型小兽恙螨群落；褐家鼠、大足鼠、黄胸鼠、大臭鼩和社鼠体表恙螨群落聚为一类，基本属于家栖小兽恙螨群落（社鼠恙螨群落例外），在此群落类型中，相应恙螨群落的小兽宿主在动物分类上的亲缘关系比较接近，同属于鼠科（大臭鼩例外）。与其他小兽比较，贝氏树鼩、珀氏长吻松鼠的栖息环境及其在动物分类上的相似性较低。其体表恙螨群落聚类顺序明显推后，独自归成一类。结论 小兽的生境分布对其体表恙螨群落类型的影响比较突出。在生境选择相近的前提下，小兽宿主在动物分类上的关系越近，其体表恙螨群落相似程度越高。

Studies on the similarity and classification of chigger mite communties on small mammals in the surrounding areas of Erhai Lake in Dali of Yunnan, China

Objective The chigger mite communities on 12 main species of small mammals were chosen as the target in the paper for illustrating the similarity and classification of the chigger mite communities.All the data were obtained from the surrounding area of Erhai Lake in Dali of Yunnan,China.Methods The field investigation was done in the surrounding areas of Erhai Lake and the small mammals were captured with mouse traps in different habitats.All the chigger mites,together with their small mammal hosts,were then identified into species respectively.Hierachical clustering analysis was used to analyze the classification of chigger mite communities.On the basis of calculating Block distance,within-group linkage was used in the clustering process and the final results were presented in a dendrogram.Results The 5 chigger mite communities on Apodenus chevrieri,Crocidura attenuate,Mus pahari, Rattus rattus sladeni and Eothenomys miletus are obviously clustered into one group at first with a prominent similarity.These 5 chigger mite communities basically belong to domestic-rat types.Another 5 chigger mite communities on Rattus norvegicus,Rattus nitidus,Suncus murinus and Niviventer confucianus are clustered into one group and they basically belong to the wild-rat types,but the chigger mite communities on N.confucianus is an exception.In the wild-rat types of chigger mite communities,the corresponding small mammals are quite close to each other,all belonging to the same family,Muridae,in zoological taxonomy,while S.murinus is an exception.Tupaia belangeri and Dremomys pernyi are quite different from the former small mammal hosts in both habitats and taxonomic affinity and therefore the chigger mite communities on these two species of hosts form two different types of chigger mite communities alone.Conclusion Ecological habitats of small mammal hosts strongly influence the types of chigger mite communities on their body surface.When the habitat selection of the hosts is similar,the closer the taxonomic position is,the more similar the chigger mite communities on their body surface will be.