Species Investigation of Chigger Mites on the Rat,Rattus flavipectus in 16 Counties(or Towns) of Yunnan,China

Objective To understand the species composition,species distribution,the dominant species and their spatial pattern of ectoparasitic chigger mites on Rattus flavipectus(a dominant species of rats in Yunnan,China).Methods(R.flavipectus)(the host of mite) was captured with cage trap method in 16 counties(or towns) of Yunnan.All the mites on the two auricles surface of the hosts were completely collected,made into specimens and then identified under a microscope.The patch index((m~*/m)) was adopted to judge the spatial distribution patterns of the dominant chigger mite species among the different individuals on their rat hosts((R.flavipectus)). Results 725 individuals of R.flavipectus were captured only in 13 ones of those 16 counties(towns).(2 710) chigger mites(belonging to 3 subfamily,10 genus,42 species) were collected from the auricles(body surface) of 725 rat hosts(R.flavipectus) with high mite infection rate and mite index.There are four dominant mite species: Ascoschoengastia indica,(A.leechi),Walchia micropelta and Microtrombicula munda.Conclusion(The chigger) mites species on R.flavipectus is very abundant with more individuals.The distribution of the chigger mites among different individuals of(R.flavipectus) is of an aggregation pattern.