Mosquito Temporal range: Late Cretaceous (Cenomanian) – Recent | |
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Aedes aegypti , vector of yellow fever | |
Scientific classification ![]() | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Superfamily: | Culicoidea |
Family: | Culicidae Meigen, 1818 [1] |
Subfamilies | |
Diversity | |
112 genera |
Mosquitoes, the Culicidae, are a family of small flies consisting of 3,600 species. The word mosquito (formed by mosca and diminutive -ito) [2] is Spanish and Portuguese for little fly. [3] 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. The group diversified during the Cretaceous period. 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.
The mosquito life cycle consists of four stages: egg, larva, pupa, and adult. Eggs are laid on the water surface; they hatch into motile larvae that feed on aquatic algae and organic material. These larvae are important food sources for many freshwater animals, such as dragonfly nymphs, many fish, and some birds. Adult females of many species have mouthparts adapted to pierce the skin of a host and feed on blood of a wide range of vertebrate hosts, and some invertebrates, primarily other arthropods. Some species only produce eggs after a blood meal.
The mosquito's saliva is transferred to the host during the bite, and can cause an itchy rash. In addition, blood-feeding species can ingest pathogens while biting, and transmit them to other hosts. Those species include vectors of parasitic diseases such as malaria and filariasis, and arboviral diseases such as yellow fever and dengue fever. By transmitting diseases, mosquitoes cause the deaths of over 725,000 people each year.
Like all flies, mosquitoes go through four stages in their life cycles: egg, larva, pupa, and adult. The first three stages—egg, larva, and pupa—are largely aquatic, [4] the eggs usually being laid in stagnant water. [5] They hatch to become larvae, which feed, grow, and molt until they change into pupae. The adult mosquito emerges from the mature pupa as it floats at the water surface. Mosquitoes have adult lifespans ranging from as short as a week to around a month. Some species overwinter as adults in diapause. [6]
Mosquitoes have one pair of wings, with distinct scales on the surface. Their wings are long and narrow, while the legs are long and thin. The body, usually grey or black, is slender, and typically 3–6 mm long. When at rest, mosquitoes hold their first pair of legs outwards, whereas the somewhat similar Chironomid midges hold these legs forwards. [7] Anopheles mosquitoes can fly for up to four hours continuously at 1 to 2 km/h (0.62 to 1.24 mph), [8] traveling up to 12 kilometres (7.5 mi) in a night. Males beat their wings between 450 and 600 times per second, driven indirectly by muscles which vibrate the thorax. [9] [10] Mosquitoes are mainly small flies; the largest are in the genus Toxorhynchites , at up to 18 mm (0.71 in) in length and 24 mm (0.94 in) in wingspan. [11] Those in the genus Aedes are much smaller, with a wingspan of 2.8 to 4.4 mm (0.11 to 0.17 in). [12]
Mosquitoes can develop from egg to adult in hot weather in as few as five days, but it may take up to a month. [13] At dawn or dusk, within days of pupating, males assemble in swarms, mating when females fly in. [14] The female mates only once in her lifetime, attracted by the pheromones emitted by the male. [15] [16] As a species that need blood for the eggs to develop, the female finds a host and drinks a full meal of blood. She then rests for two or three days to digest the meal and allow her eggs to develop. She is then ready to lay the eggs and repeat the cycle of feeding and laying. [14] Females can live for up to three weeks in the wild, depending on temperature, humidity, their ability to obtain a blood meal, and avoiding being killed by their vertebrate hosts. [14] [17]
The eggs of most mosquitoes are laid in stagnant water, which may be a pond, a marsh, a temporary puddle, a water-filled hole in a tree, or the water-trapping leaf axils of a bromeliad. Some lay near the water's edge while others attach their eggs to aquatic plants. A few, like Opifex fuscus , can breed in salt-marshes. [5] Wyeomyia smithii breeds in the pitchers of pitcher plants, its larvae feeding on decaying insects that have drowned there. [18]
Oviposition, egg-laying, varies between species. Anopheles females fly over the water, touching down or dapping to place eggs on the surface one at a time; their eggs are roughly cigar-shaped and have floats down their sides. A female can lay 100–200 eggs in her lifetime. [14] Aedes females drop their eggs singly, on damp mud or other surfaces near water; their eggs hatch only when they are flooded. [19] Females in genera such as Culex, Culiseta , and Uranotaenia lay their eggs in floating rafts. [20] [21] Mansonia females in contrast lay their eggs in arrays, attached usually to the under-surfaces of waterlily pads. [22]
Clutches of eggs of most mosquito species hatch simultaneously, but Aedes eggs in diapause hatch irregularly over an extended period. [19]
The mosquito larva's head has prominent mouth brushes used for feeding, a large thorax with no legs, and a segmented abdomen. It breathes air through a siphon on its abdomen, so must come to the surface frequently. It spends most of its time feeding on algae, bacteria, and other microbes in the water's surface layer. It dives below the surface when disturbed. It swims either by propelling itself with its mouth brushes, or by jerkily wriggling its body. It develops through several stages, or instars, molting each time, after which it metamorphoses into a pupa. [13] Aedes larvae, except when very young, can withstand drying; they go into diapause for several months if their pond dries out. [19]
The head and thorax of the pupa are merged into a cephalothorax, with the abdomen curving around beneath it. The pupa or "tumbler" can swim actively by flipping its abdomen. Like the larva, the pupa of most species must come to the surface frequently to breathe, which they do through a pair of respiratory trumpets on their cephalothoraxes. They do not feed; they pass much of their time hanging from the surface of the water by their respiratory trumpets. If alarmed, they swim downwards by flipping their abdomens in much the same way as the larvae. If undisturbed, they soon float up again. The adult emerges from the pupa at the surface of the water and flies off. [13]
Both male and female mosquitoes feed on nectar, aphid honeydew, and plant juices, [17] but in many species the females are also blood-sucking ectoparasites. In some of those species, a blood meal is essential for egg production; in others, it just enables the female to lay more eggs. [23] Both plant materials and blood are useful sources of energy in the form of sugars. Blood supplies more concentrated nutrients, such as lipids, but the main function of blood meals is to obtain proteins for egg production. [24] [25] Mosquitoes like Toxorhynchites reproduce autogenously, not needing blood meals. Disease vector mosquitoes like Anopheles and Aedes are anautogenous, requiring blood to lay eggs. Many Culex species are partially anautogenous, needing blood only for their second and subsequent clutches of eggs. [26]
Blood-sucking mosquitoes favour particular host species, though they are less selective when food is short. Different mosquito species favor amphibians, reptiles including snakes, birds, and mammals. For example, Culiseta melanura sucks the blood of passerine birds, but as mosquito numbers rise they attack mammals including horses and humans, causing epidemics of Eastern equine encephalitis virus in North America. [27] Loss of blood from many bites can add up to a large volume, occasionally causing the death of livestock as large as cattle and horses. [28] Malaria-transmitting mosquitoes seek out caterpillars and feed on their haemolymph, [29] impeding their development. [30]
Most mosquito species are crepuscular, feeding at dawn or dusk, and resting in a cool place through the heat of the day. [31] Some species, such as the Asian tiger mosquito, are known to fly and feed during daytime. [32] Female mosquitoes hunt for hosts by smelling substances such as carbon dioxide (CO2) and 1-octen-3-ol (mushroom alcohol, found in exhaled breath) produced from the host, and through visual recognition. [33] The semiochemical that most strongly attracts Culex quinquefasciatus is nonanal. [34] Another attractant is sulcatone. [35] A large part of the mosquito's sense of smell, or olfactory system, is devoted to sniffing out blood sources. Of 72 types of odor receptors on its antennae, at least 27 are tuned to detect chemicals found in perspiration. [36] In Aedes, the search for a host takes place in two phases. First, the mosquito flies about until it detects a host's odorants; then it flies towards them, using the concentration of odorants as its guide. [37] Mosquitoes prefer to feed on people with type O blood, an abundance of skin bacteria, high body heat, and pregnant women. [38] [39] Individuals' attractiveness to mosquitoes has a heritable, genetically controlled component. [40]
The multitude of characteristics in a host that is observed by the mosquito allows it to select its host to feed on. This occurs when a mosquito notes the presence of CO2, as it then activates its odour and visual search behaviours, ones that otherwise would not be used. In terms of a mosquito’s olfactory system, chemical analysis has revealed that people who are highly attractive to mosquitoes produce significantly more carboxylic acids. [41] A human's unique body odour indicates that the target is actually a human host rather than some other living warm-blooded animal (as the presence of CO2 shows). Body odour, composed of volatile organic compounds emitted from the skin of humans, is the most important cue used by mosquitoes. [42] Variation in skin odour is caused by body weight, hormones, genetic factors, and metabolic or genetic disorders. Infections such as malaria can influence an individual’s body odour. People infected by malaria produce relatively large amounts of Plasmodium-induced aldehydes in the skin, creating large cues for mosquitoes as it increases the attractiveness of an odour blend, imitating a "healthy" human odour. Infected individuals produce larger amounts of aldehydes heptanal, octanal, and nonanal. These compounds are detected by mosquito antennae. Thus, people infected with malaria are more prone to mosquito biting. [43]
Contributing to a mosquito's ability to activate search behaviours, a mosquito's visual search system includes sensitivity to wavelengths from different colours. Mosquitoes are attracted to longer wavelengths, correlated to the colours of red and orange as seen by humans, and range through the spectrum of human skin tones. In addition, they have a strong attraction to dark, high-contrast objects, because of how longer wavelengths are perceived against a lighter-coloured background. [44]
Different species of mosquitoes have evolved different methods of identifying target hosts. Study of a domestic form and an animal-biting form of the mosquito Aedes aegypti showed that the evolution of preference for human odour is linked to increases in the expression of the olfactory receptor AaegOr4. This recognises a compound present at high levels in human odour called sulcatone. However, the malaria mosquito Anopheles gambiae also has OR4 genes strongly activated by sulcatone, yet none of them are closely related to AaegOr4, suggesting that the two species have evolved to specialise in biting humans independently. [45]
Female mosquito mouthparts are highly adapted to piercing skin and sucking blood. Males only drink sugary fluids, and have less specialized mouthparts. [46]
Externally, the most obvious feeding structure of the mosquito is the proboscis, composed of the labium, U-shaped in section like a rain gutter, which sheaths a bundle (fascicle) of six piercing mouthparts or stylets. These are two mandibles, two maxillae, the hypopharynx, and the labrum. The labium bends back into a bow when the mosquito begins to bite, staying in contact with the skin and guiding the stylets downwards. The extremely sharp tips of the labrum and maxillae are moved backwards and forwards to saw their way into the skin, with just one thousandth of the force that would be needed to penetrate the skin with a needle, resulting in a painless insertion. [47] [48] [49]
Mosquito saliva contains enzymes that aid in sugar feeding, [50] and antimicrobial agents that control bacterial growth in the sugar meal. [51]
For a mosquito to obtain a blood meal, it must circumvent its vertebrate host's physiological responses. Mosquito saliva blocks the host's hemostasis system, with proteins that reduce vascular constriction, blood clotting, and platelet aggregation, to ensure the blood keeps flowing. [52] It modulates the host's immune response via a mixture of proteins which lower angiogenesis and immunity; create inflammation; [52] [53] suppress tumor necrosis factor release from activated mast cells; [54] suppress interleukin (IL)-2 and IFN-γ production; [55] [56] suppress T cell populations; [57] [58] [59] decrease expression of interferon−α/β, making virus infections more severe; [60] [61] increase natural killer T cells in the blood; and decrease cytokine production. [62]
Females of many blood-feeding species need a blood meal to begin the process of egg development. A sufficiently large blood meal triggers a hormonal cascade that leads to egg development. [63] Upon completion of feeding, the mosquito withdraws her proboscis, and as the gut fills up, the stomach lining secretes a peritrophic membrane that surrounds the blood. This keeps the blood separate from anything else in the stomach. Like many Hemiptera that survive on dilute liquid diets, many adult mosquitoes excrete surplus liquid even when feeding. This permits females to accumulate a full meal of nutrient solids. The blood meal is digested over a period of several days. [64] Once blood is in the stomach, the midgut synthesizes protease enzymes, primarily trypsin assisted by aminopeptidase, that hydrolyze the blood proteins into free amino acids. These are used in the synthesis of vitellogenin, which in turn is made into egg yolk protein. [65]
Mosquitoes have a cosmopolitan distribution, occurring in every land region except Antarctica and a few islands with polar or subpolar climates, such as Iceland, which is essentially free of mosquitoes. [66] This absence is probably caused by Iceland's climate. Its weather is unpredictable, freezing but often warming suddenly in mid-winter, making mosquitoes emerge from pupae in diapause, and then freezing again before they can complete their life cycle. [67] [68]
Eggs of temperate zone mosquitoes are more tolerant of cold than the eggs of species indigenous to warmer regions. [69] [70] Many can tolerate subzero temperatures, while adults of some species can survive winter by sheltering in microhabitats such as buildings or hollow trees. [71] In warm and humid tropical regions, some mosquito species are active for the entire year, but in temperate and cold regions they hibernate or enter diapause. Arctic or subarctic mosquitoes, like some other arctic midges in families such as Simuliidae and Ceratopogonidae may be active for only a few weeks annually as melt-water pools form on the permafrost. During that time, though, they emerge in huge numbers in some regions and may take up to 300 ml of blood per day from each animal in a caribou herd. [72]
For a mosquito to transmit disease, there must be favorable seasonal conditions, [73] primarily humidity, temperature, and precipitation. [74] El Niño affects the location and number of outbreaks in East Africa, Latin America, Southeast Asia and India. Climate change impacts the seasonal factors and in turn the dispersal of mosquitoes. [75] Climate models can use historic data to recreate past outbreaks and to predict the risk of vector-borne disease, based on an area's forecasted climate. [76] Mosquito-borne diseases have long been most prevalent in East Africa, Latin America, Southeast Asia, and India. An emergence in Europe was observed early in the 21st century. It is predicted that by 2030, the climate of southern Great Britain will be suitable for transmission of Plasmodium vivax malaria by Anopheles mosquitoes for two months of the year, and that by 2080, the same will be true for southern Scotland. [77] [78] Dengue fever, too, is spreading northwards with climate change. The vector, the Asian tiger mosquito Aedes albopictus , has by 2023 established across southern Europe and as far north as much of northern France, Belgium, Holland, and both Kent and West London in England. [79]
Mosquito larvae are among the commonest animals in ponds, and they form an important food source for freshwater predators. Among the many aquatic insects that catch mosquito larvae are dragonfly and damselfly nymphs, whirligig beetles, and water striders. Vertebrate predators include fish such as catfish and the mosquitofish, amphibians including the spadefoot toad and the giant tree frog, freshwater turtles such as the red-eared slider, and birds such as ducks. [80]
Emerging adults are consumed at the pond surface by predatory flies including Empididae and Dolichopodidae, and by spiders. Flying adults are captured by dragonflies and damselflies, by birds such as swifts and swallows, and by vertebrates including bats. [81]
Mosquitoes are parasitised by hydrachnid mites, ciliates such as Glaucoma , microsporidians such as Thelania, and fungi including species of Saprolegniaceae and Entomophthoraceae. [81]
Several flowers including members of the Asteraceae, Rosaceae and Orchidaceae are pollinated by mosquitoes, which visit to obtain sugar-rich nectar. They are attracted to flowers by a range of semiochemicals such as alcohols, aldehydes, ketones, and terpenes. Mosquitoes have visited and pollinated flowers since the Cretaceous period. It is possible that plant-sucking exapted mosquitoes to blood-sucking. [17]
Ecologically, blood-feeding mosquitoes are micropredators, small animals that feed on larger animals without immediately killing them. Evolutionary biologists see this as a form of parasitism; in Edward O. Wilson's phrase "Parasites ... are predators that eat prey in units of less than one." [82] Micropredation is one of six major evolutionarily stable strategies within parasitism. It is distinguished by leaving the host still able to reproduce, unlike the activity of parasitic castrators or parasitoids; and having multiple hosts, unlike conventional parasites. [83] [84] From this perspective, mosquitoes are ectoparasites, feeding on blood from the outside of their hosts, using their piercing mouthparts, rather than entering their bodies. Unlike some other ectoparasites such as fleas and lice, mosquitoes do not remain constantly on the body of the host, but visit only to feed. [84]
The oldest insects that have been considered to be mosquitoes are Libanoculex intermedius found in Lebanese amber, dating to the Barremian age of the Early Cretaceous, around 125 million years ago. The mouthparts of male individuals of this species are similar to living female mosquitoes, indicating that they consumed blood, unlike living male mosquitoes. [86] However, the affinity of Libanoculex as a mosquito is questioned in a 2024 study: it may be a chaoborid fly instead. [87] Three other species of Cretaceous mosquito are known. Burmaculex antiquus and Priscoculex burmanicus are known from Burmese amber from Myanmar, which dates to the earliest part of the Cenomanian age of the Late Cretaceous, around 99 million years ago. [88] [89] Paleoculicis minutus , is known from Canadian amber from Alberta, Canada, which dates to the Campanian age of the Late Cretaceous, around 79 million years ago. [90] P. burmanicus has been assigned to the Anophelinae, indicating that the split between this subfamily and the Culicinae took place over 99 million years ago. [89] Molecular estimates suggest that this split occurred 197.5 million years ago, during the Early Jurassic, but that major diversification did not take place until the Cretaceous. [91]
Over 3,600 species of mosquitoes in 112 genera have been described. They are traditionally divided into two subfamilies, the Anophelinae and the Culicinae, which carry different diseases. Roughly speaking, protozoal diseases like malaria are transmitted by anophelines, while viral diseases such as yellow fever and dengue fever are transmitted by culicines. [92]
The name Culicidae was introduced by the German entomologist Johann Wilhelm Meigen in his seven-volume classification published in 1818–1838. [93] Mosquito taxonomy was advanced in 1901 when the English entomologist Frederick Vincent Theobald published his 5-volume monograph on the Culicidae. [94] He had been provided with mosquito specimens sent in to the British Museum (Natural History) from around the world, on the 1898 instruction of the Secretary of State for the Colonies, Joseph Chamberlain, who had written that "in view of the possible connection of Malaria with mosquitoes, it is desirable to obtain exact knowledge of the different species of mosquitoes and allied insects in the various tropical colonies. I will therefore ask you ... to have collections made of the winged insects in the Colony which bite men or animals." [95]
Mosquitoes are members of a family of true flies (Diptera): the Culicidae (from the Latin culex, genitive culicis, meaning "midge" or "gnat"). [96] The phylogenetic tree is based on the FLYTREE project. [97] [98]
Diptera |
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(true flies) |
Kyanne Reidenbach and colleagues analysed mosquito phylogenetics in 2009, using both nuclear DNA and morphology of 26 species. They note that Anophelinae is confirmed to be rather basal, but that the deeper parts of the tree are not well resolved. [99]
Culicidae |
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Mosquitoes are vectors for many disease-causing microorganisms including bacteria, viruses, and protozoan parasites. Nearly 700 million people acquire a mosquito-borne illness each year, resulting in over 725,000 deaths. [100] Common mosquito-borne viral diseases include yellow fever [101] and dengue fever transmitted mostly by Aedes aegypti . [102] Parasitic diseases transmitted by mosquitoes include malaria and lymphatic filariasis. The Plasmodium parasites that cause malaria are carried by female Anopheles mosquitoes. Lymphatic filariasis, the main cause of elephantiasis, is spread by a wide variety of mosquitoes. [103] A bacterial disease spread by Culex and Culiseta mosquitoes is tularemia. [104]
Many measures have been tried for mosquito control, including the elimination of breeding places, exclusion via window screens and mosquito nets, biological control with parasites such as fungi [105] [106] and nematodes, [107] or predators such as fish, [108] [109] [110] copepods, [111] dragonfly nymphs and adults, and some species of lizard and gecko. [112] Another approach is to introduce large numbers of sterile males. [113] Genetic modification methods including cytoplasmic incompatibility, chromosomal translocations, sex distortion and gene replacement, solutions seen as inexpensive and not subject to vector resistance, have been explored. [114] Control of disease-carrying mosquitoes using gene drives has been proposed. [115] [116]
Insect repellents are applied on skin and give short-term protection against mosquito bites. The chemical DEET repels some mosquitoes and other insects. [117] Some CDC-recommended repellents are picaridin, eucalyptus oil (PMD), and ethyl butylacetylaminopropionate (IR3535). [118] Pyrethrum (from Chrysanthemum species, particularly C. cinerariifolium and C. coccineum) is an effective plant-based repellent. [119] Electronic insect repellent devices that produce ultrasounds intended to keep away insects (and mosquitoes) are marketed. No EPA or university study has shown that these devices prevent humans from being bitten by a mosquito. [120]
Mosquito bites lead to a variety of skin reactions and more seriously to mosquito bite allergies. [121] Such hypersensitivity to mosquito bites is an excessive reaction to mosquito saliva proteins. [122] Numerous species of mosquito can trigger such reactions, including Aedes aegypti , A. vexans , A. albopictus , Anopheles sinensis , Culex pipiens , [123] Aedes communis , Anopheles stephensi , [124] C. quinquefasciatus , C. tritaeniorhynchus , [125] and Ochlerotatus triseriatus . [126] Cross-reactivity between salivary proteins of different mosquitoes implies that allergic responses may be caused by virtually any mosquito species. [127] Treatment can be with anti-itch medications, including some taken orally, such as diphenhydramine, or applied to the skin like antihistamines or corticosteroids such as hydrocortisone. Aqueous ammonia (3.6%) also provides relief. [128] Both topical heat [129] and cold may be useful as treatments. [130]
Ancient Greek beast fables including "The Elephant and the Mosquito" and "The Bull and the Mosquito", with the general moral that the large beast does not even notice the small one, derive ultimately from Mesopotamia. [131]
The peoples of Siberia have origin myths surrounding the mosquito. One Ostiak myth tells of a man-eating giant, Punegusse, who is killed by a hero but will not stay dead. The hero eventually burns the giant, but the ashes of the fire become mosquitoes that continue to plague mankind. Other myths from the Yakuts, Goldes (Nanai people), and Samoyed have the insect arising from the ashes or fragments of some giant creature or demon. Similar tales found in Native North American myth, with the mosquito arising from the ashes of a man-eater, suggest a common origin. The Tatars of the Altai had a variant of the same myth, involving the fragments of the dead giant, Andalma-Muus, becoming mosquitoes and other insects. [132]
Lafcadio Hearn tells that in Japan, mosquitoes are seen as reincarnations of the dead, condemned by the errors of their former lives to the condition of Jiki-ketsu-gaki, or "blood-drinking pretas". [133]
Winsor McCay's 1912 film How a Mosquito Operates was one of the earliest works of animation. It has been described as far ahead of its time in technical quality. [134] It depicts a giant mosquito tormenting a sleeping man. [135]
Twelve ships of the Royal Navy have borne the name HMS Mosquito or the archaic form of the name, HMS Musquito. [136]
The de Havilland Mosquito was a high-speed aircraft manufactured between 1940 and 1950, and used in many roles. [137]
Aedes albopictus, from the mosquito (Culicidae) family, also known as the (Asian) tiger mosquito or forest mosquito, is a mosquito native to the tropical and subtropical areas of Southeast Asia. In the past few centuries, however, this species has spread to many countries through the transport of goods and international travel. It is characterized by the white bands on its legs and body.
Anopheles is a genus of mosquito first described by the German entomologist J. W. Meigen in 1818, and are known as nail mosquitoes and marsh mosquitoes. Many such mosquitoes are vectors of the parasite Plasmodium, a genus of protozoans that cause malaria in birds, reptiles, and mammals, including humans. The Anopheles gambiae mosquito is the best-known species of marsh mosquito that transmits the Plasmodium falciparum, which is a malarial parasite deadly to human beings; no other mosquito genus is a vector of human malaria.
Aedes aegypti, the yellow fever mosquito, is a mosquito that can spread dengue fever, chikungunya, Zika fever, Mayaro and yellow fever viruses, and other disease agents. The mosquito can be recognized by black and white markings on its legs and a marking in the form of a lyre on the upper surface of its thorax. This mosquito originated in Africa, but is now found in tropical, subtropical and temperate regions throughout the world.
Mosquito control manages the population of mosquitoes to reduce their damage to human health, economies, and enjoyment. Mosquito control is a vital public-health practice throughout the world and especially in the tropics because mosquitoes spread many diseases, such as malaria and the Zika virus.
The discipline of medical entomology, or public health entomology, and also veterinary entomology is focused upon insects and arthropods that impact human health. Veterinary entomology is included in this category, because many animal diseases can "jump species" and become a human health threat, for example, bovine encephalitis. Medical entomology also includes scientific research on the behavior, ecology, and epidemiology of arthropod disease vectors, and involves a tremendous outreach to the public, including local and state officials and other stake holders in the interest of public safety.
Culex pipiens is a species of mosquito commonly referred to as the common house mosquito or northern house mosquito, as it is the most common mosquito to the northern regions of the US. They can be found in both urban and suburban temperate and tropical regions across the world.
Culex restuans is a species of mosquito known to occur in Canada, the United States, Mexico, Guatemala, Honduras, and the Bahamas. It is a disease vector for St. Louis encephalitis and West Nile virus. In 2013 West Nile Virus positive specimens were collected in Southern California.
Mosquito-borne diseases or mosquito-borne illnesses are diseases caused by bacteria, viruses or parasites transmitted by mosquitoes. Nearly 700 million people contract mosquito-borne illnesses each year, resulting in more than a million deaths.
VectorBase is one of the five Bioinformatics Resource Centers (BRC) funded by the National Institute of Allergy and Infectious Diseases (NIAID), a component of the National Institutes of Health (NIH), which is an agency of the United States Department of Health and Human Services. VectorBase is focused on invertebrate vectors of human pathogens working with the sequencing centers and the research community to curate vector genomes.
Hematophagy is the practice by certain animals of feeding on blood. Since blood is a fluid tissue rich in nutritious proteins and lipids that can be taken without great effort, hematophagy is a preferred form of feeding for many small animals, such as worms and arthropods. Some intestinal nematodes, such as Ancylostomatids, feed on blood extracted from the capillaries of the gut, and about 75 percent of all species of leeches are hematophagous. The spider Evarcha culicivora feeds indirectly on vertebrate blood by specializing on blood-filled female mosquitoes as their preferred prey. Some fish, such as lampreys and candirus; mammals, especially vampire bats; and birds, including the vampire finch, Hood mockingbird, Tristan thrush, and oxpeckers, also practise hematophagy.
Anopheles albimanus is a species of mosquito in the order Diptera. It is found in coastal Central and South America, the Caribbean, and Mexico. It is a generalist species and capable of wide dispersion. A. albimanus is a common malaria vector.
Anopheles stephensi is a primary mosquito vector of malaria in urban India and is included in the same subgenus as Anopheles gambiae, the primary malaria vector in Africa. A. gambiae consists of a complex of morphologically identical species of mosquitoes, along with all other major malaria vectors; however, A. stephensi has not yet been included in any of these complexes. Nevertheless, two races of A. stephensi exist based on differences in egg dimensions and the number of ridges on the eggs; A. s. stephensisensu stricto, the type form, is a competent malaria vector that is found in urban areas, and A. s. mysorensis, the variety form, exists in rural areas and exhibits considerable zoophilic behaviour, making it a poor malaria vector. However, A. s. mysorensis is a detrimental vector in Iran. An intermediate form also exists in rural communities and peri-urban areas, though its vector status is unknown. About 12% of malaria cases in India are due to A. stephensi.
Aedes koreicus, the Korean bush mosquito is a species of mosquito in the genus Aedes. The adults are relatively large with a black and white pattern on their legs and other body parts. Clear longitudinal lines on the dorsal part of the thorax distinguish it from Ae. aegypti and Ae. albopictus. The species bears close morphological, ecological, and genetic similarity to the Asian bush mosquito, Aedes japonicus, but can be physically distinguished by a pale basal band on the hind tarsomere.
Toxorhynchites (Toxorhynchites) splendens is a species of non-hematophagous mosquito belonging to the genus Toxorhynchites. It is widely used as a predator to control dengue mosquitoes.
Culex (Lutzia) fuscanus is a species of mosquito belonging to the genus Culex. It is found in China, India, Indonesia and Sri Lanka They are natural predators of disease causing mosquito larva such as Aedes aegypti, Anopheles subpictus, and Culex tritaeniorhynchus.
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.
Toxorhynchites rutilus, also known as the elephant mosquito or treehole predatory mosquito, is a species of mosquito in the family Culicidae. Unlike most species in the genus that populate the tropics, Tx. rutilus is endemic to temperate regions. As their name suggests, these mosquitoes commonly lay their eggs in treeholes where their larvae are predators on a variety of arthropods. As with other mosquitoes, they also inhabit other bodies of stagnant water such as in a tire or artificial containers. but not large bodies of water like ponds and ground pools. Females are able to strategically locate breeding sites that already contain prey to oviposit in.
Aedes taeniorhynchus, or the black salt marsh mosquito, is a mosquito in the family Culicidae. It is a carrier for encephalitic viruses including Venezuelan equine encephalitis and can transmit Dirofilaria immitis. It resides in the Americas and is known to bite mammals, reptiles, and birds. Like other mosquitoes, Ae. taeniorhynchus adults survive on a combination diet of blood and sugar, with females generally requiring a blood meal before laying eggs.
Aedes circumluteolus is a species of mosquito that is found throughout much of Sub-Saharan Africa. It is often found in tropical coastal lowlands and Bushveld savanna.
Only female mosquitoes require a blood meal (protein)...The number of egg formation and development in ovary of the female is directly dependent on quantum and nature supply of blood meal.
Acquiring a blood meal (protein) is essential for egg production, but mostly both male and female mosquitoes are nectar feeders for their nutrition.
Parasites, in a phrase, are predators that eat prey in units of less than one. Tolerable parasites are those that have evolved to ensure their own survival and reproduction but at the same time with minimum pain and cost to the host.
Scientists have created spermless mosquitoes in an effort to curb the spread of malaria.