Flies are insects of the order Diptera, the name being derived from the Greek δι- di- "two", and πτερόν pteron "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced mechanosensory organs known as halteres, which act as high-speed sensors of rotational movement and allow dipterans to perform advanced aerobatics. Diptera is a large order containing an estimated 1,000,000 species including horse-flies, crane flies, hoverflies and others, although only about 125,000 species have been described.
The Bombyliidae are a family of flies. Their common name is bee flies. Adults generally feed on nectar and pollen, some being important pollinators. Larvae generally are parasitoids of other insects.
The Asiloidea comprise a very large superfamily insects in the order Diptera, the true flies. It has a cosmopolitan distribution, occurring worldwide, with many species living in dry, sandy habitat types. It includes the family Bombyliidae, the bee flies, which are parasitoids, and the Asilidae, the robber flies, which are predators of other insects. Members of the other families are mainly flower visitors as adults and predators as larvae.
The Acroceridae are a small family of odd-looking flies. They have a hump-backed appearance with a strikingly small head, generally with a long proboscis for accessing nectar. They are rare and not widely known. The most frequently applied common names are small-headed flies or hunch-back flies. Many are bee or wasp mimics. Because they are parasitoids of spiders, they also are sometimes known as spider flies.
Nannochoristidae is a family of scorpionflies with many unusual traits. It is a tiny, relict family with a single extant genus, Nannochorista, with eight species occurring in New Zealand, southeastern Australia, Tasmania, Argentina and Chile. Due to the groups distinctiveness from other scorpionflies, it is sometimes placed in its own order, the Nannomecoptera. Some studies have placed them as the closest living relatives of fleas. Most mecopteran larvae are eruciform, or shaped like caterpillars. Nannochoristid larvae, however, are elateriform, and have elongated and slender bodies. The larvae are aquatic, which is unique among mecopterans. The larvae are predatory, hunting on the beds of shallow streams, primarily on the larvae of aquatic Diptera like chironomids.
The Empidoidea are a large monophyletic superfamily of true flies, the sister taxon to the Muscomorpha (Cyclorrhapha). These two groups are sometimes united in the unranked taxon Eremoneura. There are some 10,000 known species within Empidoidea, which are represented on all continents except Antarctica. They are known to have existed since the Jurassic period.
The Limoniinae are a paraphyletic assemblage of genera within the crane flies, Tipulidae, although they can usually be distinguished by the way the wings are held at rest. Limoniines usually hold/fold the wings along the back of the body, whereas other tipulids usually hold them out at right angles. Snow flies such as Chionea scita have no wings at all. Limoniines are also usually smaller than other tipulids, with some exceptions. Limoniinae are a very large assemblage with nearly 10,500 described species in 133 genera, and were historically treated as a subfamily, but their classification is in flux; numerous authors recently treated the group at the rank of family, but subsequent phylogenetic analyses revealed that the remaining groups of tipulids render the group paraphyletic. These flies are found in damp places throughout the world, and many species form dense swarms in suitable habitats.
The Scenopinidae or window flies are a small family of flies (Diptera), distributed worldwide. In buildings, they are often taken at windows, hence the common name window flies.
Apsilocephalidae is a family of flies in the superfamily Asiloidea. The family was proposed in 1991 as a close relative of Therevidae distinguishable by genitalic characters. The family contains three extant genera and four extinct genera described from the fossil record..
Atelestidae is a family of flies in the superfamily Empidoidea. The four genera were placed in a separate family in 1983; they were formerly either in Platypezidae or considered incertae sedis. While they are doubtless the most basal of the living Empidoidea, the monophyly of the family is not fully proven. The genus Nemedina seems to represent a most ancient lineage among the entire superfamily, while Meghyperus is probably not monophyletic in its present delimitation, and it is liable to be split up eventually, with some species being placed elsewhere. In 2010, the genus Alavesia, previously only known from Cretaceous fossils, was found alive in Namibia, subsequent species were also described from Brazil.
Apystomyia is a genus of flies in the family Apystomyiidae. The genus contains the single living Apystomyiidae species, Apystomyia elinguis, which is primarily found in California. Details of its life history are largely unknown. The extinct genus Hilarimorphites is known from the Cretaceous Burmese and New Jersey ambers. Formerly placed in the Asiloidea, molecular phylogenetic studies in 2010 placed the genus unambiguously as a sister of the Cyclorrhapha within the clade Eremoneura.
Panorpida or Mecopterida is a proposed superorder of Endopterygota. The conjectured monophyly of the Panorpida is historically based on morphological evidence, namely the reduction or loss of the ovipositor and several internal characteristics, including a muscle connecting a pleuron and the first axillary sclerite at the base of the wing, various features of the larval maxilla and labium, and basal fusion of CuP and A1 veins in the hind wings. The monophyly of the Panorpida is supported by recent molecular data.
Cretomicrophorus is an extinct genus of flies in the family Dolichopodidae from the Upper Cretaceous of Russia, France and the United States. The generic name is a combination of the Latin word creta ("chalk") and the generic name Microphorus.
Microphorinae is a subfamily of flies in the family Dolichopodidae. It is part of an expanded concept of the family, Dolichopodidae sensu lato, though it was previously considered a family of its own.
Archichrysotus is an extinct genus of flies in the family Dolichopodidae. The generic name is a combination of the Greek prefix archi- and the generic name Chrysotus. The genus is known from Upper Cretaceous amber from the Taymyr Peninsula in Russia, New Jersey in the United States and Cedar Lake in Manitoba, Canada.
Eremoneura is a clade of flies within the Brachycera that includes the Empidoidea and the Cyclorrhapha and is a sister of the Asilomorpha. They are thought to have evolved around the Mesozoic. The group includes fossils described in the genus Chimeromyia from 125 million year old amber which show both empidoid and cyclorrhaphan characters. The monotypic family Apystomyiidae has also been placed within the Eremoneura as a sister of the Cyclorrhapha.
Rhagionemestriidae is an extinct family of brachyceran flies known from the Jurassic and Cretaceous periods. It was first named as a subfamily of the Nemestrinidae by Ussatchov (1968), and was raised to full family status by Nagatomi and Yang (1998). They are considered to be closely related to the family Acroceridae. Similar to Acroceridae, members of the family possess a large hemispherical head, with eyes covering nearly all of the area.
Eremochaetidae is an extinct family of brachyceran flies known from the Jurassic and Cretaceous periods of Asia. It is part of the extinct superfamily Archisargoidea. The morphology of the ovipositor of the only 3 dimensionally preserved genus Zhenia was initially interpreted as evidence of being an endoparasitoid of arthropods, however a subsequent study suggested that the ovipositor was used to deposit its eggs in plant material, similar to members of Tephritoidea. In a phylogenetic analysis, Ermochaetidae was found to be monophyletic, surrounded by a paraphyletic Archisargidae.
Tethepomyiidae is an extinct family of small brachyceran flies known from the Cretaceous period of Laurasia. It is part of the extinct superfamily Archisargoidea. The family is characterised by "very large eyes, reduced mouthparts, a highly reduced antennal flagellum, and greatly reduced venation." The ovipositor of Tethepomyia zigrasi has a hypodermic morphology likely used for injecting eggs into hosts.
Archisargidae is an extinct family of brachyceran flies known from the Jurassic and Cretaceous periods. It is part of the extinct superfamily Archisargoidea. Most members of the family are known from the Callovian-Oxfordian Daohugou biota of Inner Mongolia, China, and the equivalently aged Karabastau Formation of Kazakhstan. The family has been found to be paraphyletic with respect to Eremochaetidae in a cladistic analysis.
