Bat fly

Bat flies are members of the insect order Diptera, the true flies, which are external parasites of bats. Two families of flies are exclusively bat flies: Nycteribiidae and Streblidae. Bat flies have a cosmopolitan distribution, meaning that they are found around the world. Nycteribiidae and Streblidae are members of the superfamily Hippoboscoidea, along with the families Hippoboscidae and Glossinidae.