关键词: 玉龙鼠疫疫源地, 蚤类, 群落结构, 物种多样性, 空间分布

Abstract: Objective To understand the community structures and species diversity of fleas, and their relationship with plague prevalence in Yulong plague focus, Yunnan province. Methods According to geography and vegetation distribution, Yulong plague focus was divided into four different altitude gradients and two different habitats (forest and agricultural area). Small mammals and their ectoparasite fleas were surveyed by using snap-trap method every quarter from March to December in 2015. The spatial distribution pattern of ectoparasite fleas along environmental gradients was studied using ecological indexes. Results A total of 1 031 ectoparasite fleas belonging to 12 species of 8 genera in 3 families were collected from 1 575 small mammals which belonged to 22 species, 12 genera, 6 families and 4 orders. The predominant species of fleas were Neopsylla specialis specialis, Ctenophthalmus quadrates, and Frontopsylla spadix spadix, accounting for 86.13% of total fleas. The fleas captured in altitude gradients Ⅳ had the highest species richness(10)and number of individuals(639), which was larger than the total of individuals in other three altitude gradients. With the increase of altitude, the species richness and number of individuals increased, while diversity index of fleas showed the trend of a gradual increase followed by a decrease. Conclusion In altitude gradient Ⅳ, ectoparasite fleas had low species diversity and evenness, high dominance and the highest total flea index, and epidemic sites were centralized. Therefore, gradient Ⅳ is not only the core area of Yulong plague focus but also the key area of the plague surveillance and prevention.

Key words: Yulong plague focus, Fleas, Community structure, Species diversity, Spatial distribution