Abstract
In this work we record the highest number of bat flies species among those already performed in the Brazilian cerrado and discuss the associations and patterns of parasitism of these species and their hosts. A total of 1,390 ectoparasitic flies were collected, belonging to 24 species of Streblidae and one of Nycteribiidae, parasitizing 227 bats of 15 species. Among the species found, the presence of Trichobius sp. on Lonchophylla mordax and the first occurrence of Hershkovitzia sp. on Thyroptera devivoi are highlighted. Lophostoma species presented the highest proportion of individuals with infracommunities and the highest values of parasitological indexes. The high number of bat fly species and hosts, as well as the high values for rates of parasitism and infracommunities, suggests that this area of cerrado has good shelter conditions for these species. The abundance of species and high rates of parasitism detracts from the hypothesis that a higher mean intensity of ectoparasites results from lower competition among flies for hosts in areas with lower ectoparasite species richness. Biogeographical and historical factors of host populations, besides the number of host species and individuals sampled, may contribute to species number and intensity of parasitism.