Stalk-eyed flies are insects of the fly family Diopsidae. The family is distinguished from most other flies by most members of the family possessing "eyestalks": projections from the sides of the head with the eyes at the end. Some fly species from other families such as Drosophilidae, Platystomatidae, Richardiidae, and Tephritidae have similar heads, but the unique character of the Diopsidae is that their antennae are located on the stalk, rather than in the middle of the head as in all other flies. Stalked eyes are present in all members of the subfamily Diopsinae, but are absent in the Centrioncinae, which retain unstalked eyes similar to those of other flies. The stalked eyes are usually sexually dimorphic, with eyestalks present but shorter in females.
Hover flies of the genus Microdon are unusual among the Diptera. Like other members of the subfamily, they are myrmecophiles, meaning they inhabit the nests of ants.
The Pyrgotidae are an unusual family of flies (Diptera), one of only two families of Cyclorrhapha that lack ocelli. Most species are "picture-winged", as is typical among the Tephritoidea, but unlike other tephritoids, they are endoparasitoids; the females pursue scarab beetles in flight, laying an egg on the beetle's back under the elytra where the beetle cannot reach it. The egg hatches and the fly larva enters the body cavity of the beetle, feeding and eventually killing the host before pupating. In the United States, some species of Pyrgota and Sphecomyiella can be quite common in areas where their host beetles are abundant. Like their host beetles, these flies are primarily nocturnal, and are often attracted to artificial lights.
Ceriana is a genus of hoverfly. All species are wasp mimics.
Milesia is a genus of very large hoverflies, which mimic social wasps. For example, the European species Milesia crabroniformis is a convincing mimic of the hornet species Vespa crabro. Milesia are predominantly Palaeotropical in distribution almost entirely Oriental.
Diasemopsis is a genus of stalk-eyed flies in the family Diopsidae. They are known from sub-Saharan Africa.
Teleopsis is a genus of stalk-eyed flies in the family Diopsidae. All species in the genus are found in Asia. About 20 species are described and several others as yet are to be described.
Mydas is a genus of flies in the family Mydidae.
Metadon is a genus of hoverfly containing 43 species. Most of the species were originally described in the genus Microdon.
Suragina is a genus of flies in the family Athericidae.
