Stegomyia aegypti (Linnaeus, 1762), original combination: Culex aegypti.
Subfamily Culicinae, tribe Aedini, genus Stegomyia. Subgenus Stegomyia includes three species; the nominotypical species consists of two subspecies. Subgenus abbreviation – Stg.
Stegomyia aegypti and St. mascarensis share the 17 homoplastic characters that diagnose the subgenus in the study of Reinert et al. (2009). These characters are indicated with an asterisk (*) here. ADULTS – *Ocular scales of head all narrow; maxillary palpus with white scales; *scutal scales all narrow; *scutal fossa with distinct crescent-shaped patch of white scales; dorsocentral setae present; scutellum with broad white scales on all lobes; paratergite and subspiracular area with broad white scales; postspiracular area without scales; *lower prealar scales present; *mesepimeral scales in 2 patches; white knee spots present on all femora (except in St. mascarensis); *midfemur with median pale-scaled stripe on anterior surface; *tibiae dark anteriorly, without white band; hindtarsomeres 1–4 with a basal white bands, hindtarsomere 5 all white; *larger foreunguis of males with tooth, smaller one simple; *midungues of males both simple. FEMALE GENITALIA – *Posterior margin of tergum VIII convex, *setae inserted on posterior 0.7 or more; posterior margin of sternum VIII with deep median emargination separating broadly rounded lateral lobes; tergum IX also with deep posterior emargination. MALE GENITALIA – Tergum IX deeply concave in middle; gonostylus simple, elongate, gonostylar claw inserted at apex, *developed as relatively narrow spiniform, *bluntly pointed; aedeagus strongly toothed; paraproct with sternal arm, without apical lobed process. LARVAE – *Seta 7-II different than seta 7-I; *seta 1-VIII 0.50–0.95 length of seta 2-VIII; comb scales in single row, no comb plate; segment X with small inconspicuous spicules on posterior margin; ventral brush (seta 4-X) with 5 pairs of setae. PUPAE – *Seta 6-I and *6-II as long or shorter than seta 7-I and 7-II respectively; paddle with distinct marginal denticles; seta 1-Pa single. See genus Stegomyia.
The affinities of subgenus Stegomyia are unknown. Stegomyia aegypti and St. mascarensis and St. pia differ radically from other species of genus Stegomyia. The three species were recovered as a strongly supported monophyletic group in the maximum likelihood phylogeny of Soghigian et al. (2017) based on molecular markers.
Stegomyia aegypti is a common domestic species. It is found in cities, towns, villages and remote settlements in all types of country. The immature stages are predominantly found in artificial containers of all types, and in certain plant cavities such as the axils of fan banana, bamboo stumps and less frequently in tree holes and other phytotelmata in the vicinity of human habitation. Females are principally diurnal biters but feeding may occur any time between sunrise and sunset. Females are also known to attack humans at night in artificial light and even total darkness. Larvae of St. mascarensis have been found in tree holes and rock holes. Females bite humans in forested areas.
Stegomyia aegypti is the most important vector of dengue fever virus. Chikungunya virus has been isolated from this species in Thailand and has been shown to be a vector of this pathogen in Tanzania. It is the principal vector of yellow fever virus in tropical areas of Africa and Central and South America, and is known to harbour many other arboviruses.
The nominotypical species, St. aegypti, occurs nearly everywhere in tropical and warm temperate regions of the world, reaching northern and southern latitudes where larval habitats are not subject to freezing. It is probably native to the Afrotropical Region, and has been spread to other areas through commerce. The sole other species of the subgenus, St. mascarensis, is only known to occur on the island of Mauritius.
As subgenus of Aedes: Christophers, 1960 (biology of St. aegypti); Belkin, 1962 (Aegypti Group, South Pacific, taxonomy, distribution, bionomics); McClelland et al., 1973 (St. mascarensis, bionomics); Huang, 1979 (Aegypti Group, Oriental Region, taxonomy, distribution, bionomics); Lee et al., 1987 (Aegypti Group, Australia, taxonomy, literature review, bionomics); Reinert, 2000 (Aegypti Assemblage, female genitalia); Huang, 2004 (Aegypti Group, Afrotropical Region, taxonomy). As subgenus Stegomyia: Reinert et al., 2009 (subgeneric status, morphology, phylogeny); Rattanarithikul et al., 2010 (St. aegypti, Thailand, keys, disease relations, bionomics); Soghigian et al., 2017 (as subgenus of Aedes, phylogenetic relationships).