Anopheles

[1] Many such mosquitoes are vectors of the parasite Plasmodium, a genus of protozoans that cause malaria in birds, reptiles, and mammals, including humans.

[6] The cladogram is based on an analysis of mosquito genomes by Heafsey and colleagues in 2015:[6] gambiae complex (Africa) A. epirotus & spp.

[8] The taxonomy of the genus was greatly advanced in 1901 when the English entomologist Frederick Vincent Theobald described 39 Anopheles species in his 5-volume monograph on the Culicidae.

[9] He was 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.

[16] The mosquito larva has a well-developed head with mouth brushes used for feeding, a large thorax and a nine-segment abdomen.

In contrast to other mosquitoes, the Anopheles larva lacks a respiratory siphon, so it positions itself so that its body is parallel to the surface of the water.

In contrast, the feeding larva of culicine mosquitoes attach themselves to the water surface with the posterior siphon, the body pointing downwards.

Larvae of Anopheles have been found in freshwater or saltwater marshes, mangrove swamps, rice fields, grassy ditches, the edges of streams and rivers, and small, temporary rain pools.

These palps carry the receptors for carbon dioxide, a major attractant that enables the mosquito to locate its host.

The blood is digested over time, serving as a source of protein for the production of eggs, which gradually fill the abdomen.

[16] Anopheles can be distinguished from other mosquitoes by the palps, which are as long as the proboscis, and by the presence of discrete blocks of black and white scales on the wings.

Males cannot feed on blood, as it appears to produce toxic effects and kills them within a few days, around the same lifespan as a water-only diet.

[18] Females feed on sugar sources for energy, but usually require a blood meal for the development of eggs.

Their lifespans depend on temperature, humidity, and their ability to successfully obtain a blood meal while avoiding host defenses.

[26] The jumping spider Evarcha culicivora indirectly feeds on vertebrate blood by preying on female Anopheles.

[28] Juvenile spiders have adopted an Anopheles-specific prey-capture behavior, using the posture of Anopheles as a primary cue to identify them.

[29] Since the genus Anopheles is the sole vector for malaria, it has been studied intensively in the search for effective control methods.

One important behavioral factor is the degree to which an Anopheles species prefers to feed on humans (anthropophily) or animals such as cattle or birds (zoophily).

Most Anopheles are not exclusively anthropophilic or zoophilic, including the primary malaria vector in the western United States, A.

[16] It is not possible to measure directly the lifespans of mosquitoes in nature, but indirect estimates of daily survivorship have been made for several Anopheles species.

Estimates of daily survivorship in Tanzania of A. gambiae, the vector of the dangerous Plasmodium falciparum parasite, ranged from 0.77 to 0.84, meaning that after one day, between 77% and 84% have survived.

[32] Assuming this survivorship is constant through the adult life of a mosquito, less than 10% of female A. gambiae would survive longer than a 14-day extrinsic incubation period.

Biting by nocturnal, endophagic Anopheles can be markedly reduced through the use of insecticide-treated bed nets or through improved housing construction to prevent mosquito entry (e.g. window screens).

The larval and pupal gut is largely colonized by photosynthetic cyanobacteria, while in the adult, gram-negative bacteria in the Pseudomonadota and Bacteroidota phyla predominate.

However, mosquitoes, with a short generation time, may rapidly evolve resistance, as experienced during the Global Malaria Eradication Campaign of the 1950s.

Such a gene drive system has been shown to suppress an entire caged A. gambiae population[37] within 7–11 generations, typically less than a year.

This has raised concerns with both the efficiency of a gene drive system as well as the ethical and ecological impact of such an eradication program.

Anopheles eggs with their distinctive side floats
Resting positions of adult Anopheles (A, B) are more upright than that of Culicinae (C).
Global distribution of Anopheles species covers both the tropics with numerous malarias, and colder areas not subject to malaria at the start of the 21st century. [ 20 ]
Person wearing personal protective equipment performing indoor residual spraying on a house to prevent mosquitoes.
Person wearing personal protective equipment performing indoor residual spraying on a house to prevent malaria.