Taxonomy of Anopheles | |
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Anopheles stephensi | |
Scientific classification ![]() | |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Family: | Culicidae |
Subfamily: | Anophelinae |
Genus: | Anopheles |
Subgenera | |
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Anopheles is a genus of mosquitoes (Culicidae) comprising over 500 recognized species. [1] These mosquitoes are the primary vectors responsible for transmitting malaria to humans. [2]
The genus is taxonomically divided into several subgenera, including Anopheles (206 species), Baimaia (one species), Cellia (239 species), Kerteszia (12 species), Lophopodomyia (six species), Nyssorhynchus (34 species), and Stethomyia (five species). [3] Notably, only about 30 to 40 of these species are commonly involved in malaria transmission. [4]
The classification of this genus began in 1901 with Frederick Vincent Theobald. [5] Despite the passage of time, the taxonomy remains incompletely settled. [6] [7] [8] Classification into species is based on morphological characteristics - wing spots, head anatomy, larval and pupal anatomy, and chromosome structure, and more recently on DNA sequences. [9] [10] [11] [12]
The genus Anopheles belongs to a subfamily Anophelinae with three genera: Anopheles Meigen (nearly worldwide distribution), Bironella Theobald (Australia only: 11 described species) and Chagasia Cruz (Neotropics: four described species). The genus Bironella has been divided into three subgenera: Bironella Theobald (two species), Brugella Edwards (three species) and Neobironella Tenorio (three species). Bironella appears to be the sister taxon to the Anopheles, with Chagasia forming the outgroup in this subfamily.
The type species of the genus is Anopheles maculipennis . [13]
The genus has been subdivided into seven subgenera based primarily on the number and positions of specialized setae on the gonocoxites of the male genitalia. The system of subgenera originated with the work of Christophers, who in 1915 described three subgenera: Anopheles (widely distributed), Myzomyia (later renamed Cellia ) (Old World) and Nyssorhynchus (Neotropical). Nyssorhynchus was first described as Lavernia by Theobald. Frederick Wallace Edwards in 1932 added the subgenus Stethomyia (Neotropical distribution). Kerteszia was also described by Edwards in 1932, but then was recognised as a subgrouping of Nyssorhynchus. It was elevated to subgenus status by Komp in 1937; this subgenus is also found in the Neotropics. Two additional subgenera have since been recognised: Baimaia (Southeast Asia only) by Harbach et al. in 2005 and Lophopodomyia (Neotropical) by Antunes in 1937.
One species within each subgenus has been identified as the type species of that particular subgenus:
Within the genus Anopheles are two main groupings, one formed by the Cellia and Anopheles subgenera and a second by Kerteszia, Lophopodomyia, and Nyssorhynchus. Subgenus Stethomyia is an outlier with respect to these two taxa. Within the second group, Kerteszia and Nyssorhynchus appear to be sister taxa. Cellia appears to be more closely related to the Kerteszia-Lophopodomyia-Nyssorhynchus group than to Anopheles or Stethomyia, tentatively suggesting the following branching order: ( Stethomyia ( Anopheles ( Cellia ( Lophopodomyia ( Kerteszia, Nyssorhynchus))))).
The number of species currently recognised within the subgenera is given here in parentheses: Anopheles (206 species), Baimaia (one), Cellia (239), Kerteszia (12), Lophopodomyia (six), Nyssorhynchus (34) and Stethomyia (five).
The subgenus Baimaia may be elevated to genus level, as it appears to be a sister group to Bironella and all other Anopheles. [16]
Taxonomic units between subgenus and species are not currently recognised as official zoological names. In practice, a number of taxonomic levels have been introduced. The larger subgenera (Anopheles, Cellia, and Nyssorhynchus) have been subdivided into sections and series, which in turn have been divided into groups and subgroups. Below subgroup but above species level is the species complex. Taxonomic levels above species complex can be distinguished on morphological grounds. Species within a species complex are either morphologically identical or extremely similar and can only be reliably separated by microscopic examination of the chromosomes or DNA sequencing. The classification continues to be revised.
The first species complex was described in 1926 when the problem of nontransmission of malaria by Anopheles gambiae was solved by Falleroni, who recognised that An. gambiae was a complex of six species, of which only four could transmit malaria. This complex has subsequently been revised to a total of seven species of which five transmit malaria.
Subgenus Nyssorhynchus has been divided in three sections: Albimanus (19 species), Argyritarsis (11 species) and Myzorhynchella (four species). The Argyritarsis section has been subdivided into Albitarsis and Argyritarsis groups.
The Anopheles group was divided by Edwards into four series: Anopheles (worldwide), Myzorhynchus (Palearctic, Oriental, Australasian and Afrotropical), Cycloleppteron (Neotropical) and Lophoscelomyia (Oriental); and two groups, Arribalzagia (Neotropical) and Christya (Afrotropical). Reid and Knight (1961) modified this classification by subdividing the subgenus Anopheles into two sections, Angusticorn and Laticorn and six series. The division was based on the shape of their pupal trumpets. The Laticorn section was created for those species with wide, funnel-shaped trumpets having the longest axis transverse to the stem, and the Angusticorn section for species with semitubular trumpets having the longest axis vertical more or less in line with the stem. The earlier Arribalzagia and Christya groups were considered to be series. The Angusticorn section includes members of the Anopheles, Cycloleppteron, and Lophoscelomyia series, and the Laticorn section includes the Arribalzagia (24 species), Christya, and Myzorhynchus series.
Cellia is the largest subgenus: all species within this subgenus are found in the Old World. It has been divided into six series - Cellia (eight species), Myzomyia (69 species), Neocellia (33 species), Neomyzomyia (99 species), Paramyzomyia (six species) and Pyretophorus (22 species). This classification was developed by Grjebine (in 1966), Reid (in 1968), and Gillies & de Meillon (also in 1968) [17] based on the work by Edwards in 1932. Series definition within this subgenus is based on the cibarial armature - a collection of specialized spicules borne ventrally at the posterior margin of the cibarium - which was first used as a taxonomic method by Christophers in 1933.
Kerteszia is a small subgenus found in South America whose larvae have specific ecological requirements; these can only develop within water that accumulates at the base of the follicular axis of the epiphytic Bromeliaceae. Unlike the majority of mosquitoes, species in this subgenus are active during the day.
Within a number of species, separate subspecies have been identified. The diagnostic criteria and characteristic features of each subgenus are discussed on the own page.
Anopheles nuneztovari is a species complex with at least one occurring in Colombia and Venezuela and another occurring in the Amazon Basin. [18]
Species that have been shown to be vectors of human malaria are marked with a star (*) after the name.
The following are currently regarded as nomina nuda:
A subgroup of Anopheles gambiae sensu stricto has been reported and given the name Goundry. This subgroup has not yet been elevated to species status. [26]
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