Unplaced species of Tabanidae
These species do not currently belong to a generic classification, and are considered incertae sedis, Latin for "of uncertain placement."
There are about 4,500 species of horse fly. These flies are known for the painful bite that many have. Horse flies mostly eat nectar, but females must eat blood before laying eggs. The black horse fly lives mostly in the eastern US. It often attacks farm animals, causing serious blood loss. It can also carry diseases that harm animals and people.
- “Horsefly.” Wikipedia, the Free Encyclopedia. Available from: http://en.wikipedia.org/wiki/Horse-fly
- Long, W. 2001. "Tabanus atratus" (On-line), Animal Diversity Web. Accessed January 26, 2012 http://animaldiversity.ummz.umich.edu/site/accounts/information/Tabanus_atratus.html.
The Chrysops spp. (Deer flies) are fairly large and often brightly patterned in yellow and black. They favor open woodlands and bite deer and other warm-blooded animals. The larvae feed on decaying vegetable matter in shallow water. The adults may obtain nectar from flowers, but they are not important pollinators. Horseflies are even larger, and found in pastures or prairies where there are large hoofed animals. They bite these animals to lap their blood. Their larvae occur in muddy areas and are carnivorous. The adult Horseflies are more likely to use flowers as a place to perch, than anything else.
Excerpt from "A phylogeny of long-tongued horse flies (Diptera:Tabanidae:Philoliche) with the first cladistic review of higher relationships within the family"
Unfortunately, the presence of the hind tibial spurs is variable within the Pangoniinae, adding uncertainty to an already taxonomically challenging group. Mackerras (1954) attempted to single-handedly solve this issue by exploring genital characters in Tabanidae. His work came shortly after Hennig (1950) published his first version of Phylogenetic Systematics in German and before Hennig’s concepts of cladistics began to take hold among the scientific community following the English translation (Hennig 1966). Mackerras (1954: p. 431) felt that division by the presence of hind tibial spurs placed the ‘chrysopines unhappily with the pangoniines, and separated them from the tabanines, to which they seemed to me to be much more closely related’. Examination of genitalia convinced him that the Chrysopsini was indeed more closely related to the Tabanini than to the presumably more ancient and plesiomorphic Pangoniini. As such, he proposed the first phylogenetic hypothesis for the Tabanidae based on what he believed to be shared, derived characters (synapomorphies). In this scheme, the Tabanidae contained the Pangoniinae, Scepsidinae, Chrysopsinae and Tabaninae, with the latter two as sister taxa (see Fig. 2b). In the words of Philip (1957: p. 550) this began ‘a new era’ in Tabanidae systematics. Mackerras also suggested that the Chrysopsinae was intermediate, with the Tabaninae evolving from it as a more recent group. This can only be shown if reciprocal monophyly by extinction has failed to occur leaving the Chrysopsinae paraphyletic.
Currently, most authors accept a classification based on Mackerras’ hypothesis and adopt the following subfamilies and tribes: Chrysopsinae (Bouvieromyiini, Chrysopsini, Rhinomyzini), Tabaninae (Diachlorini, Haematopotini, Tabanini), and Pangoniinae (Pangoniini, Philolichini, Scionini) (Chainey 1993). Scepsidinae is a controversial subfamily of four monotypic genera that share a lack of functional mouthparts in adults (Oldroyd 1957; Fairchild 1969; McAlpine 1981; Fairchild and Burger 1994). They only occur in the coastal sands of south-east Africa and Brazil and are considered by most authors to be grouped based on convergent morphology. Some authors also support the Mycertomyiini as a fourth tribe under Pangoniinae based on its bizarre genital structure (Coscarón and Philip 1979; Fairchild and Burger 1994).
- Morita, S. I. (2008) A phylogeny of long-tongued horse flies (Diptera:Tabanidae:Philoliche) with the first cladistic review of higher relationships within the family. Invertebrate Systematics, 22, 311–327
Known prey organisms
Based on studies in:
New Zealand: Otago, German, Kye Burn catchment (River)
This list may not be complete but is based on published studies.
- Townsend, CR, Thompson, RM, McIntosh, AR, Kilroy, C, Edwards, ED, Scarsbrook, MR. 1998. Disturbance, resource supply and food-web architecture in streams. Ecology Letters 1:200-209.
Molecular Biology and Genetics
Statistics of barcoding coverage
|Specimen Records:||2,655||Public Records:||13|
|Specimens with Sequences:||2,273||Public Species:||12|
|Specimens with Barcodes:||2,007||Public BINs:||4|
|Species With Barcodes:||240|
Locations of barcode samples
|This article needs additional citations for verification. (July 2010)|
Horse-fly is the most widely-used English common name for members of the family Tabanidae. Apart from the common name "horse-flies", broad categories of biting, bloodsucking Tabanidae are variously known as breeze flies, clegs or clags, deer flies, gadflies, or zimbs. In some areas of Canada, they also are known as Bull Dog Flies. In Australia some species are known as "March flies", a name that in other English-speaking countries refers to a very different Dipteran family, the non-bloodsucking Bibionidae.
The Tabanidae are true flies, that is to say, members of the insect order Diptera. Tabanid species that habitually attack humans and livestock are widely regarded as pests because of the bites that females of most species inflict, and the diseases and parasites that some species transmit. The various species of Tabanidae range from medium-sized to very large in size. Some species, such as deer flies and the Australian March flies, are known for being extremely noisy during flight, though clegs, for example, fly quietly and bite with little warning.
In spite of their roles as pests, Tabanidae also are important pollinators of some flowers. In particular, several South African species have spectacularly long proboscides adapted to the extraction of nectar from flowers with long, narrow corolla tubes, such as Lapeirousia and some Pelargoniums. Tabanidae occur worldwide, being absent only at extreme northern and southern latitudes.
Taxonomy and description 
The genus Zophina is of uncertain placement, though it has been classified among the Pangoniinae. Two well-known genera are the common horse flies, genus Tabanus Linnaeus, 1758 and the deer flies, genus Chrysops Meigen, 1802 are also known as banded horse flies because of their coloring. Both genera give their names to subfamilies. The "Blue Tail Fly" in the eponymous song was probably a tabanid common to the southeastern United States.
Adult horse flies feed on nectar and sometimes pollen. Females of most species are anautogenous, meaning they require a blood meal before they are able to reproduce effectively, if at all. Much like male mosquitoes, male Tabanidae are not ectoparasitic and lack the mouth parts (mandibles) that the females use in drawing the blood on which they feed. Most female horse flies feed on mammalian blood, but some species are known to feed on birds or reptiles. Some are said to attack amphibians as well.
Biting behaviour 
Horsefly bites are painful, the bites of large specimens especially so. Most short tongued (short proboscid) species of horse flies use their knife-like mandibles to rip and/or slice flesh apart. Flies with longer proboscides bite more like a mosquito, their stylet-like mouthparts piercing the host's skin like needles.
The horse fly's bite is more immediately painful than that of its mosquito counterparts, although it still aims to escape before its victim responds. Moreover, the pain of a horse fly bite may mean that the victim is more concerned with assessing the wound, and not swatting the interloper. In any case defense is difficult, considering the agile nature of the fly. However, inhabitants of regions where the flies are a pest usually learn to swat immediately at the first hint of the bite. That usually gets the fly, especially if its escape is hampered by its having bitten through clothing. The bites may become itchy, sometimes causing a large swelling afterward if not treated quickly.
Eggs are laid on stones or vegetation usually close to water. On hatching, the larvae fall into water or moist earth, feeding voraciously on invertebrates, such as snails, earthworms and other insects.
Tabanidae are known vectors for some blood-borne diseases of animals and humans. Tabanidae are very good vectors of the equine infectious anaemia virus, as well as some Trypanosoma species. Species in the genus Chrysops are biological vectors of Loa loa, transmitting this parasitic filarial worm between humans. They have also been known to transmit anthrax among cattle and sheep and tularemia between rabbits and humans (and are the most common vector of such transmission in the Western US).
Blood loss is a common problem in some animals, when large flies are abundant. Some animals have been known to lose up to 300 ml of blood in a single day from tabanid bites, which can severely weaken or even kill them.
See also 
A tabanid from the Western Ghats, India
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