[Investigation of chigger mites on the rat Eothenomys miletus in Yunnan].
OBJECTIVE
To understand the species, species distribution, the dominant species and their interspecies interaction of chigger mites on Eothenomys miletus(a dominant species of rats) in Yunnan.


METHODS
The rats were captured with mouse traps in 16 counties (or cities) during 2000-2004. All mites on the surface of two auricles of the hosts were collected and identified. The patch index (m*/m) and the coefficient of association (V) were adopted to judge the spatial distribution patterns and interspecies interaction of the dominant chigger mite species among different individuals of the rats (E. miletus).


RESULTS
1157 individuals of E. miletus were captured from 16 counties (citys). 37613 chigger mites (belonging to 3 subfamily, 9 genus and 80 species) were collected from the auricles (body surface) of 1157 rat hosts with a high "overall mite infestation rate" (68.2%) and "overall mite index" (32.5). Six species of mites were found dominant on E. miletus: Leptotrombidium scutellare, Leptotrombidium sinicum, Helenicula simena, Leptotrombidium eothenomydis, Herpetacarus hastoclavus and Leptotrombidium hiemalis. The distribution of the chigger mites among different individuals of E.miletus showed an aggregation pattern. Both positive and negative association existed between each two dominant species of chigger mites.


CONCLUSIONS
The species composition of chigger mites on Eothenomys miletus is complex with abundant individuals, which reflects a high species diversity of the mites. The main species of chigger mites tend to an aggregation on the body surface of E. miletus.
Hou
Shu-xin
SX
Faculty of Basic Medicine, Dali University, Dali 671000, China.
Guo
Xian-guo
XG
Men
Xing-yuan
XY
Niu
Ai-qin
AQ
Dong
Wen-ge
WG
Shi
Wu-xiang
WX
D000465:Algorithms; D000818:Animals; D003411:Arvicolinae / Q000469:parasitology*; D044822:Biodiversity; D002681:China; D006790:Host-Parasite Interactions; D008924:Mite Infestations / Q000469:parasitology*; D008925:Mites / Q000145:classification / Q000254:growth & development*; D013045:Species Specificity