A black fly or blackfly[1] (sometimes called a buffalo gnat, turkey gnat, or white socks) is any member of the family Simuliidae of the Culicomorphainfraorder. It is related to the Ceratopogonidae, Chironomidae, and Thaumaleidae. Over 2,200 species of black flies have been formally named, of which 15 are extinct.[2] They are divided into two subfamilies: Parasimuliinae contains only one genus and four species; Simuliinae contains all the rest. Over 1,800 of the species belong to the genus Simulium.[2]
Most black flies gain nourishment by feeding on the blood of mammals, including humans, although the males feed mainly on nectar. They are usually small, black or gray, with short legs, and antennae. They are a common nuisance for humans, and many U.S. states have programs to suppress the black fly population. They spread several diseases, including river blindness in Africa (Simulium damnosum and S. neavei) and the Americas (S. callidum and S. metallicum in Central America, S. ochraceum in Central and South America).
Eggs are laid in running water, and the larvae attach themselves to rocks. Breeding success is highly sensitive to water pollution.[3] The larvae use tiny hooks at the ends of their abdomens to hold on to the substrate, using silk holdfasts and threads to move or hold their place. They have foldable fans surrounding their mouths, also termed "mouth brushes".[4]The fans expand when feeding, catching passing debris (small organic particles, algae, and bacteria). The larva scrapes the fan's catch into its mouth every few seconds. Black flies depend on lotic habitats to bring food to them. They will pupate under water and then emerge in a bubble of air as flying adults. They are often preyed upon by trout during emergence. The larva of some South African species are known to be phoretic on mayfly nymphs.
A female black fly
Adult males feed on nectar, while females exhibit anautogeny and feed on blood before laying eggs. Some species in Africa can range as far as 40mi (64km) from aquatic breeding sites in search of their blood meals, while other species have more limited ranges.
Different species prefer different host sources for their blood meals, which is sometimes reflected in the common name for the species. They feed in the daytime, preferably when wind speeds are low.
Black flies may be either univoltine or multivoltine, depending on the species. The number of generations a particular pest species has each year tends to correlate with the intensity of human efforts to control those pests.
Work conducted at Portsmouth University in 1986–1987[citation needed] indicates Simulium spp. create highly acidic conditions within their midguts. This acidic environment provides conditions ideally suited to bacteria that metabolise cellulose. Insects cannot metabolise cellulose independently, but the presence of these bacteria allows cellulose to be metabolised into basic sugars. This provides nutrition to the black fly larvae, as well as the bacteria. This symbiotic relationship indicates a specific adaptation, as fresh-flowing streams could not provide sufficient nutrition to the growing larva in any other way.[citation needed]
Regional effects of black fly populations
Black flies attack a canoe expedition in July 2015 in the Canadian Arctic, Dubawnt River, Nunavut.
Black flies are a scourge to livestock in Canada, causing weight loss in cattle and sometimes death.[5]
Pennsylvania operates the largest single black fly control program in North America. The program is seen as beneficial to both the quality of life for residents and to the state's tourism industry.[6]
The Blandford fly (Simulium posticatum) in England was once a public health problem in the area around Blandford Forum, Dorset, due to its large numbers and the painful lesions caused by its bite. It was eventually controlled by carefully targeted applications of Bacillus thuringiensis israelensis.[7] In 2010, a summer surge of insect bites blamed on the Blandford fly required many who had been bitten to be treated in a hospital.[8]
In parts of Scotland, various species of black flies are a nuisance and bite humans, mainly between May and September. They are found mainly in mixed birch and juniper woodlands, and at lower levels in pine forests, moorlands, and pastures. Bites are most often found on the head, neck, and back. They also frequently land on legs and arms.
In Peninsular Malaysia 35 species of preimaginal black flies were discovered in a study in 2016, including Simulium digrammicum, which had been considered locally extinct.[10]
Public health
Only four genera in the family Simuliidae, Simulium, Prosimulium, Austrosimulium, and Cnephia, contain species that feed on people, though other species prefer to feed on other mammals or on birds. Simulium, the type genus, is the most widespread and is a vector for several diseases, including river blindness.
Mature adults can disperse tens or hundreds of miles from their breeding grounds in fresh flowing water, under their own power and assisted by prevailing winds, complicating control efforts. Swarming behavior can make outdoor activities unpleasant or intolerable, and can affect livestock production. During the 18th century, the "Golubatz fly" (Simulium colombaschense) was a notorious pest in central Europe.[11] Even non-biting clouds of black flies, whether composed of males or of species that do not feed on humans or do not require a blood meal before egg laying, can form a nuisance by swarming into orifices.
Bites are shallow and accomplished by first stretching the skin using teeth on the labrum and then abrading it with the maxillae and mandibles, cutting the skin and rupturing its fine capillaries. Feeding is facilitated by a powerful anticoagulant in the flies' saliva, which also partially numbs the site of the bite, reducing the host's awareness of being bitten and thereby extending the flies' feeding time. Biting flies feed during daylight hours only and tend to zero in on areas of thinner skin, such as the nape of the neck or ears and ankles.
Itching and localized swelling and inflammation sometimes result from a bite. Swelling can be quite pronounced depending on the species and the individual's immune response, and irritation may persist for weeks. Intense feeding can cause "black fly fever", with headache, nausea, fever, swollen lymph nodes, and aching joints; these symptoms are probably a reaction to a compound from the flies' salivary glands. Less common severe allergic reactions may require hospitalization.[12][13]
Repellents provide some protection against biting flies. Products containing the active ingredient ethyl butylacetylaminopropionate (IR3535), DEET (N,N-diethyl-meta-toluamide), or picaridin are most effective. Some beauty products have been found effective, and their use as insect repellents have been approved by EPA (e.g., Skin So Soft).[14] However, given the limited effectiveness of repellents, protecting oneself against biting flies requires taking additional measures, such as avoiding areas inhabited by the flies, avoiding peak biting times, and wearing heavy-duty, light-colored clothing, including long-sleeve shirts, long pants and hats. When black flies are numerous and unavoidable, netting that covers the head, like the “bee bonnets” used by beekeepers, can provide protection.[15]
River blindness
Black flies are central to the transmission of the parasiticnematodeOnchocerca volvulus which causes onchocerciasis, or "river blindness". It serves as the larval host for the nematode and acts as the vector by which the disease is spread. The parasite lives on human skin and is transmitted to the black fly during feeding.[13]
Crosskey R. W.; The natural history of blackflies. Willey, New York, 1990. ISBN0-471-92755-4
Honomichl K.; Bellmann, H.; Biologie und Ökologie der Insekten. CD-Rom. Gustav Fischer, Stuttgart, 1994. ISBN0271004177
Jedlicka, L.; Stloukalova, V.; Family Simuliidae. pp.331–347 in: Papp, L. and Darvas, B. (eds.): Contributions to a Manual of Palaearctic Diptera, Volume 2. Science Herald, Budapest, 1997.
Jensen, F.; Diptera Simuliidae, Blackflies. pp.209–241 in: Nilsson, A.N. (ed.): Aquatic Insects of North Europe. A Taxonomic Handbook. Apollo Books, Stenstrup, 1997.
Kim, K. C.; Merritt, R. W. (Eds.); Black flies, ecology, population management, and annotat. world list. University Park, London, 1987. ISBN0-271-00417-7
Kurtak, D. C. 1973. Observations on filter feeding by the larvae of black flies. PhD thesis. Cornell Univ., Ithaca. 157 pp.
Kurtak, D. C. 1978. "Efficiency of filter feeding of black fly larvae". Can. J. ZooL 56:1608–23 110.
Laird, M. (Ed.); Blackflies. Academic Press, London, 1981. ISBN0124340601
Lechthaler, W.; Car, M.; Simuliidae − Key to Larvae and Pupae from Central− and Western Europe. Vienna 2005, ISBN3-9501839-3-0
Seitz, G.; Verbreitung und Ökologie der Kriebelmücken (Diptera: Simuliidae) in Niederbayern. in: Lauterbornia. Mauch, Dinkelscherben 11.1992, pp.1–230.
Timm, T.; Dormanzformen bei Kriebelmücken unter besonderer Berücksichtigung des Ei-Stadiums (Diptera: Simuliidae). in: Entomologia generalis. Schweizerbart, Stuttgart 12.1987, 133–142. ISSN0340-2266
Timm, T.; Unterschiede in Habitatselektion und Eibiologie bei sympatrischen Kriebelmückenarten (Diptera, Simuliidae). in: Mitteilungen der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie. Bremen 6.1988, 156–158. ISSN0344-9084
Timm, T.; Rühm, W. (Hrsg.); Beiträge zur Taxonomie, Faunistik und Ökologie der Kriebelmücken in Mitteleuropa. Essener Ökologische Schriften. Bd.2. Westarp Wissenschaften, Magdeburg 1993. ISBN3-89432-078-8
Wichard, W.; Arens, W.; Eisenbeis, G.; Atlas zur Biologie der Wasserinsekten. Stuttgart, 1994. ISBN3-437-30743-6
Wirtz, H. P.; Analyse der Histaminanteile im Speichel verschiedener Kriebelmückenarten (Diptera: Simuliidae). in: Mitteilungen der Deutschen Gesellschaft für Allgemeine und Angewandte Entomologie. Bremen 6.1988, 441–442. ISSN0344-9084
Mosquitoes, the Culicidae, are a family of small flies consisting of 3,600 species. The word mosquito is Spanish and Portuguese for little fly. Mosquitoes have a slender segmented body, one pair of wings, three pairs of long hair-like legs, and specialized, highly elongated, piercing-sucking mouthparts. All mosquitoes drink nectar from flowers; females of some species have in addition adapted to drink blood. Evolutionary biologists view mosquitoes as micropredators, small animals that parasitise larger ones by drinking their blood without immediately killing them. Medical parasitologists view mosquitoes instead as vectors of disease, carrying protozoan parasites or bacterial or viral pathogens from one host to another.
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, mosquitoes and others, although only about 125,000 species have been described.
Horse-flies and deer flies are true flies in the family Tabanidae in the insect order Diptera. The adults are often large and agile in flight. Only female horseflies bite land vertebrates, including humans, to obtain blood. They prefer to fly in sunlight, avoiding dark and shady areas, and are inactive at night. They are found all over the world except for some islands and the polar regions. Both horse-flies and botflies (Oestridae) are sometimes referred to as gadflies.
A midge is any small fly, including species in several families of non-mosquito Nematoceran Diptera. Midges are found on practically every land area outside permanently arid deserts and the frigid zones. Some midges, such as many Phlebotominae and Simuliidae, are vectors of various diseases. Many others play useful roles as prey for insectivores, such as various frogs and swallows. Others are important as detritivores, and form part of various nutrient cycles. The habits of midges vary greatly from species to species, though within any particular family, midges commonly have similar ecological roles.
Sandfly or sand fly is a colloquial name for any species or genus of flying, biting, blood-sucking dipteran (fly) encountered in sandy areas. In the United States, sandfly may refer to certain horse flies that are also known as "greenheads", or to members of the family Ceratopogonidae. The bites usually result in a small, intensely itchy bump or welt, the strength of which intensifies over a period of 5-7 days before dissipating. Moderate relief is achieved with varying success through the application of over the counter products such as Benadryl (ingested) or an analgesic cream such as After Bite. Outside the United States, sandfly may refer to members of the subfamily Phlebotominae within the Psychodidae. Biting midges (Ceratopogonidae) are sometimes called sandflies or no-see-ums. New Zealand sandflies are in the genus of sand fly Austrosimulium, a type of black fly.
Leptoconops torrens is a species of small biting flies in the no-see-um family Ceratopogonidae. They were first mentioned in writing by Charles Henry Tyler Townsend in 1893. The name Leptoconops carteri is a junior synonym of L. torrens. They are prevalent in the southwestern and southeastern areas of the United States. In early stages of life, L. torrens flies dwell in soil, then emerge to feed and breed as fully developed adults.
The Nematocera are a suborder of elongated flies with thin, segmented antennae and mostly aquatic larvae. This group is paraphyletic and contains all flies but species from suborder Brachycera, which includes more commonly known species such as the housefly or the common fruit fly. The equivalent clade to Nematocera is the whole Diptera, with Brachycera as a subclade. Families in Nematocera include mosquitoes, crane flies, gnats, black flies, and multiple families commonly known as midges. The Nematocera typically have fairly long, fine, finely-jointed antennae. In many species, such as most mosquitoes, the female antennae are more or less threadlike, but the males have spectacularly plumose antennae.
The Blandford fly is a species of black fly. It is a biting insect found in Europe, Turkey and western Siberia. It spends its larval stage in the weedbeds of slow flowing rivers and when the fly emerges, the female seeks a blood meal before mating. It usually bites the lower legs causing pain, itching and swelling. Scratching the irritated areas can lead to breaks in the skin, after which infection may set in.
The Sciaridae are a family of flies, commonly known as dark-winged fungus gnats. Commonly found in moist environments, they are known to be a pest of mushroom farms and are commonly found in household plant pots. This is one of the least studied of the large Diptera families, probably due to the small size of these insects and the similarity among species.
The Lonchaeidae are a family of acalyptrate flies commonly known as lance flies. About 500 described species are placed into 9 genera. These are generally small but robustly built flies with blue-black or metallic bodies. They are found, mainly in wooded areas, throughout the world with the exception of polar regions and New Zealand.
Simulium is a genus of black flies, which may transmit diseases such as onchocerciasis.
Chironomus plumosus, also known as the buzzer midge, is a species of nonbiting midge (Chironomidae) that occurs throughout areas in the Northern Hemisphere.
Austrosimulium is a genus of 31 species of black flies that are distributed in Australia and New Zealand. There are 2 subgenera: Austrosimulium whose species are principally from New Zealand, and Novaustrosimulium which are exclusively Australian. Austrosimulium is a sister genus to the monospecific Paraustrosimulium of South America.
Mansonella ozzardi is a filarial (arthropod-borne) nematode (roundworm). This filarial nematode is one of two that causes serous cavity filariasis in humans. The other filarial nematode that causes it in humans is Mansonella perstans. M. ozzardi is an endoparasite that inhabits the serous cavity of the abdomen in the human host. It lives within the mesenteries, peritoneum, and in the subcutaneous tissue.
Smittium is a genus of fungi in the order Harpellales. It is the largest genus in the order. As of 2013, there were 81 described species. Many of these have been formally described only recently; in 1998 there were just 46. Several have been transferred to Smittium from other genera, such as Orphella, Rubetella, Genistella, and Typhella. In general, the genus has a cosmopolitan distribution, but some species are limited to small regions.
A gnat is any of many species of tiny flying insects in the dipterid suborder Nematocera, especially those in the families Mycetophilidae, Anisopodidae and Sciaridae. They can be both biting and non-biting. Most often they fly in large numbers, called clouds. "Gnat" is a loose descriptive category rather than a phylogenetic or other technical term, so there is no scientific consensus on what constitutes a gnat. Some entomologists consider only non-biting flies to be gnats. Certain universities and institutes also distinguish eye gnats: the Smithsonian Institution describes them as "non-biting flies, no bigger than a few grains of salt, ... attracted to fluids secreted by your eyes".
Diachlorus ferrugatus, commonly known as the yellow fly in the United States or doctor fly in Belize, is a species of highly aggressive biting horse-fly of the family Tabanidae native to North and Central America to Costa Rica.
Austrosimulium is a subgenus of Austrosimulium, a genus of Simuliidae. The flies in this subgenre are found mainly in New Zealand, with a few in Australia. They are the only Simuliidae found in New Zealand.
Many species of flies of the two-winged type, Order Diptera, such as mosquitoes, horse-flies, blow-flies and warble-flies, cause direct parasitic disease to domestic animals, and transmit organisms that cause diseases. These infestations and infections cause distress to companion animals, and in livestock industry the financial costs of these diseases are high. These problems occur wherever domestic animals are reared. This article provides an overview of parasitic flies from a veterinary perspective, with emphasis on the disease-causing relationships between these flies and their host animals. The article is organized following the taxonomic hierarchy of these flies in the phylum Arthropoda, order Insecta. Families and genera of dipteran flies are emphasized rather than many individual species. Disease caused by the feeding activity of the flies is described here under parasitic disease. Disease caused by small pathogenic organisms that pass from the flies to domestic animals is described here under transmitted organisms; prominent examples are provided from the many species.
Austrosimulium australense, known as the New Zealand black fly or more commonly sandfly, is a species of small fly of the family Simuliidae, endemic to New Zealand. Females consume blood for nutrients to produce eggs, and it is one of three species of Austrosimulium in New Zealand that often bite humans.
This page is based on this Wikipedia article Text is available under the CC BY-SA 4.0 license; additional terms may apply. Images, videos and audio are available under their respective licenses.
