Bat flies - obligate ectoparasites of bats

Bat flies (Diptera: Hippoboscoidea) are highly specialized ectoparasites and only associate with bats (Mammalia: Chiroptera). They live in the fur and on the wing membranes where they feed on host blood. Bat flies are nominally divided into two cosmopolitan families, Streblidae and Nycteribiidae, but recent phylogenetic studies suggest these are not natural groups (Dittmar et al. 2006). Nycteribiids (275 species) are more speciose in the Eastern Hemisphere, whereas the streblids (227 species) are richer in the Western. Generally, both families are most diverse in the tropics, less diverse in subtropics, and rather impoverished in temperate regions. However, this latitudinal richness gradient is more pronounced in the Western Hemisphere. Mystacinobia zelandica (Mystacinobiidae) has been considered a “bat fly” (Holloway 1976). This fly is a roost associate with and phoretic on the endemic New Zealand bat Mystacina tuberculata. Unlike members of the Nycteribiidae and Streblidae, M. zelandica feeds on guano, not host blood. Molecular analysis places M. tuberculata within the Oestroidea (Gleeson et al. 2000). This chapter summarizes current understanding of the taxonomy, life history, and breeding biology of flies allocated to Streblidae and Nycteribiidae, and offers overviews of morphology, behavior, specificity, ecology, and cospeciation in the context of the parasitehost association.