* Araucnephia * Araucnephioides * Archicnephia * Austrosimulium * Baisomyia * Cnephia * Cnesia * Cnesiamima * Crozetia * Ectemnia * Gigantodax * Greniera * Gydarina * Gymnopais * Kovalevimyia * Levitinia * Lutzsimulium * Mayacnephia * Metacnephia * Paracnephia * Parasimulium * Paraustrosimulium * Pedrowygomyia * Prosimulium * Simuliites * Simulimima * Simulium * Stegopterna * Sulcicnephia * Titanopteryx * Tlalocomyia * Twinnia
Data related to
A BLACK FLY (sometimes called a BLANDFORD FLY, BUFFALO GNAT , TURKEY
GNAT, or WHITE SOCKS) is any member of the family SIMULIIDAE of the
Culicomorpha infraorder . They are related to the
* 1 Ecology * 2 Regional effects of black fly populations
* 3 Public health
* 3.1 River blindness
* 4 See also * 5 Notes * 6 References * 7 External links * 8 Bibliography
Eggs are laid in running water, and the larvae attach themselves to rocks. Breeding success is highly sensitive to water pollution. 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. 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
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 indicates Simulium spp. create highly acidic conditions within their midguts. This basic environment provides conditions ideally suited to bacteria that metabolise cellulose. Insects cannot metabolise cellulose independently, but the presence of these bacteria allow 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.
REGIONAL EFFECTS OF BLACK FLY POPULATIONS
Black flies attack a canoe expedition in July 2015 in the
Canadian Arctic, Dubawnt River ,
* In the wetter parts of the northern latitudes of
Only four genera in the Simuliidae family, 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 kilometers 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. 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.
Repellents provide some protection against biting flies. Products
containing the active ingredient
Black flies are central to the transmission of the parasitic nematode Onchocerca 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.
* ^ Daley, Beth (2008-06-23). "Black flies surge in Maine\'s clean
rivers". Boston Globe. Retrieved 2008-06-23.
* ^ The Canadian Encyclopedia: Black