The Streblidae are a family of flies in the superfamily Hippoboscoidea, and together with their relatives the Nycteribiidae, are known as bat flies. They are winged or wingless ectoparasites of bats, and often have long legs. They appear to be host-specific, with different species of bat flies occurring only on particular species of bat hosts, sometimes with multiple species of flies sharing a host bat. Systematics The 237 or so species are divided among roughly 33 genera and five subfamilies. The monophyly of this family has not been supported. The streblid subfamily Trichobiinae may be more closely related to the Nycteriboscinae and other lineages in the Nycteribiidae. Several authors favor splitting the family into an Old World lineage consisting of the Ascodipterinae and Nycteriboscinae and a New World lineage containing all other subfamilies. The former would be named Ascodipterinae and the latter would retain the name Streblidae. Alternatively, the Streblidae and Nycteribiidae might be united as a monophyletic family containing all bat flies. Subfamilies are here listed in presumed order of most ancient to most recently evolved. Selected genera are also given, sorted alphabetically, as too little is known about their interrelationships. Subfamily Brachytarsininae Speiser 1900 (sometimes Nycteriboscinae) Genus Brachytarsina Macquart, 1851 Genus Megastrebla Maa, 1971 Subgenus Aoroura Subgenus Megastrebla Maa, 1971 Genus Raymondia Frauenfeld, 1855 Genus Raymondiodes Jobling, 1954 Subfamily Ascodipterinae Monticelli 1898 Genus Ascodipteron Adensamer, 1896 Genus Maabella Hastriter & Bush, 2006 Genus Paraascodipteron Advani & Vazirani, 1981 Subfamily Nycterophiliinae Wenzel, 1966 Genus Nycterophilia Ferris, 1916 Genus Phalconomus Wenzel, 1984 Subfamily Streblinae Speiser, 1900 Genus Anastrebla Wenzel, 1966 Genus Metelasmus Coquillett, 1907 Genus Paraeuctenodes Pessôa & Guimarães, 1937 Genus Strebla Wiedemann, 1824 Subfamily Trichobiinae Jobling, 1936 Genus Anatrichobius Wenzel, 1966 Genus Aspidoptera Coquillett, 1899 Genus Eldunnia Curran, 1934 Genus Exastinion Wenzel, 1966 Genus Joblingia Dybas & Wenzel, 1947 Genus Mastoptera Wenzel, 1966 Genus Megistopoda Macquart, 1852 Genus Megistapophysis Dick & Wenzel, 2006 Genus Neotrichobius Wenzel & Aitken, 1966 Genus Noctiliostrebla Wenzel, 1966 Genus Paradyschiria Speiser, 1900 Genus Parastrebla Wenzel, 1966 Genus Paratrichobius Costa Lima, 1921 Genus Pseudostrebla Costa Lima, 1921 Genus Speiseria Kessel, 1925 Genus Stizostrebla Jobling, 1939 Genus Synthesiostrebla Townsend, 1913 Genus Trichobioides Wenzel, 1966 Genus Trichobius Gervais, 1844 Genus Xenotrichobius Wenzel, 1976 Subfamily incertae sedis †Enischnomyia Poinar & Brown, 2012 Morphology One of the characteristic feature of streblid bat flies is their variable degree of eye reduction. The compound eyes are highly, but variably reduced, with