Genus Ochlerotatus Lynch Arribálzaga, 1891

Type species: 

Ochlerotatus confirmatus Lynch Arribálzaga, 1891b [subjective synonym of Ochlerotatus scapularis (Rondani, 1848)].

Classification: 

Subfamily Culicinae, tribe Aedini. Ochlerotatus includes 199 species. Thirteen subgenera are recognised for 74 species; 125 species are without subgeneric placement. Genus abbreviation – Oc.

Tanaka (2014, 2018), in a catalogue of the mosquitoes of Japan, recognised subgenus Woodius and six species groups (communis-, dorsalis-, excrucians-, impiger-, punctor- and sticticus-groups), which he treated as subgenera without formal names. None of the newly recognised ‘subgenera’ (species groups) were accompanied by a description or diagnosis and were listed without an explicit indication that they were new. In the absence of this, despite being included in a dichotomous key based on features of the male genitalia, they cannot be accepted as formally (validly) established subgeneric taxa (or even species groups).

Characteristics: 

Ochlerotatus is a large highly varied group of species that generally exhibit the following characteristics. Five characters (five female genitalic and one larval) that diagnose Ochlerotatus in the phylogenetic analyses of Reinert et al. (2009), based on features observed in 48 species currently included in the genus, are indicated by an asterisk (*).

ADULTS – Vertex largely with narrow decumbent scales, erect forked scales numerous; interocular space with or without scales; compound eyes more or less separated above antennal pedicels; antenna of females shorter to longer than proboscis, distinctly shorter than proboscis in males, flagellar whorls of males with numerous long setae normally directed dorsally and ventrally; maxillary palpus of females 0.15–0.40 length of proboscis, with 5 palpomeres, palpomere 5 minute, maxillary palpus of males as long or longer than proboscis, palpomeres 4 and 5 subequal, downturned and setose; scutal scales usually narrow; anterior and posterior acrostichal and dorsocentral setae normally present; scutellum with narrow scales only; paratergite usually (not always) with scales; pleural scaling and setation varied; lower mesepimeral setae present or absent; remigium of wing usually with conspicuous setae; alula with extensive marginal fringe of long piliform scales; scaling of tarsi varied; ungues varied, at least fore- and midungues usually toothed, fore- and midungues of males enlarged; abdominal scaling varied, especially tergum I and laterotergite; terga with numerous lateral setae and reduced scaling in males. FEMALE GENITALIA – Segment VIII usually completely retracted within segment VII; *tergum VIII longer than wide, *with long setae on proximal 0.4 of lateral margins; *upper vaginal sclerite absent; cercus usually long and narrow, *distal part narrowly rounded; 3 spermathecal capsules. MALE GENITALIA – Segment VIII usually narrowed proximally; ninth tergal lobes usually more or less distinct, with setae; gonocoxite usually elongate, with more or less strongly developed basal dorsomesal lobe, sometimes with apical dorsomesal lobe, mesal surface membranous from base to apex; gonostylus simple, with apical usually long spiniform gonostylar claw; claspette comprised of elongate stem with single apical blade-like, sickle-like or otherwise modified claspette filament; aedeagus simple; paraproct with strong usually simple apical spine; cercal setae present. LARVAE – Head broad; antenna short to quite long, usually distinctly spiculate; seta 1-A varied, usually inserted near mid-length of antenna; *seta 1-C spiniform; seta 4-C usually small, varied in position; setae 5,6-C caudad of antennal bases; seta 13-P absent; seta 12-I present; seta 6-I,II and seta 7-I strongly developed, seta 6-III–VI at least moderately developed; comb scales varied, in large patch or single row; siphon varied in length, pecten spines evenly spaced or distal ones more widely separated; seta 1-S inserted within or beyond pecten; saddle complete or incomplete, acus present or absent; seta 1-X usually inserted on saddle; seta 2-X multi-branched; ventral brush (seta 4-X) usually with at least 7 pairs of setae on grid and 2 or more precratal setae. PUPAE – Trumpet short, broad, tracheoid area indistinct; seta 8-CT widely separated from seta 9-CT; setae 2,3-I usually approximated, seta 2-III–VII varied in position; seta 9-VI small, similar to seta 9-II–V; paddle with or without marginal spicules; seta 1-Pa single or branched. See Aedini.

Phylogenetic relationships: 

The monophyly of Ochlerotatus is doubtful. Many species of the genus cannot be placed in any of the currently recognised subgenera. Consequently, the affinities of Ochlerotatus are very uncertain. The genus was recovered as the sister-group of a clade comprised of Acartomyia + (Jarnellius + (Halaedes + Opifex)) in the phylogeny generated in the study of Reinert et al. (2009) based on morphological data of all life stages. Ochlerotatus was not associated with other generic-level taxa in the phylogeny of Wilkerson et al. (2015). It was recovered as a polyphyletic group in the maximum likelihood phylogeny of Soghigian et al. (2017) based on molecular markers for 85 species.

Bionomics and disease relations: 

The immature stages of most species of Ochlerotatus are found in various types of temporary fresh-water ground pools, but several species inhabit rock holes, natural and artificial container habitats, and brackish water pools. Females of many species viciously attack humans and are often very troublesome pests, particularly in northern temperate regions. The majority of species bite in the daytime, particularly during crepuscular periods, but some species also feed during the night.

A number of species of Ochlerotatus are known to harbour natural infections of arboviruses and microfilariae.

Distribution: 

Ochlerotatus is a large and abundant group with species in all temperate, subtropical and tropical areas of the world. The greatest diversity of species occur in the Australian, Nearctic and Neotropical Regions. Comparatively few species are found in the Afrotropical and Oriental Regions.

Principal references: 

Belkin, 1962 (as subgenus of Aedes, morphology, bionomics, distribution); Reinert, 2000 (as subgenus of Ochlerotatus, morphology); Reinert, 2002 (as subgenus of Ochlerotatus, female genitalia); Reinert et al., 2008, 2009 (generic status, morphology, phylogeny); Rattanarithikul et al., 2010 (Thailand, keys, bionomics); Huang & Rueda, 2014 (as subgenus of Aedes, Afrotropical Region, 3 species of subgenus uncertain, key to adults); Wilkerson et al., 2015 (as subgenus of Aedes, phylogeny); Soghigian et al., 2017 (as subgenus of Aedes, phylogenetic relationships).

Species - Subgenus uncertain: 

aboriginis (Dyar, 1917)
abserratus (Felt & Young, 1904)
akkeshiensis (Tanaka, 1998)
albifasciatus (Macquart, 1838)
albineus Séguy, 1923
aloponotum (Dyar, 1917)
ambreensis (Rodhain & Boutonnier, 1983)
andersoni (Edwards, 1926)
annulipes (Meigen, 1830)
antipodeus Edwards, 1920
aurifer (Coquillett, 1903)
behningi (Martini, 1926)
bejaranoi (Martinez, Carcavallo & Prosen, 1960)
berlandi (Séguy, 1921)
biskraensis (Brunhes, 1999)
breedensis (Muspratt, 1953)
burjaticus (Kuchartshuk, 1973)
burpengaryensis (Theobald, 1905)
cacozelus (Marks, 1963)
calumnior (Belkin, Heinemann & Page, 1970)
campestris (Dyar & Knab, 1907)
camptorhynchus (Thomson, 1869)
cantans (Meigen, 1818)
cantator (Coquillett, 1903)
caspius (Pallas, 1771)
    subspecies caspius (Pallas, 1771)
    subspecies hargreavesi Edwards, 1920
    subspecies meirai (Ribeiro, da Cunha Ramos, Capela & Pires, 1980)
cataphylla (Dyar, 1916)
churchillensis (Ellis & Brust, 1973)
clivis (Lanzaro & Eldridge, 1992)
coluzzii (Rioux, Guilvard & Pasteur, 1998)
communis (de Geer, 1776)
continentalis (Dobrotworsky, 1960)
cunabulanus (Edwards, 1924)
cyprioides (Danilov & Stupin, 1982)
cyprius (Ludlow, 1920)
dahlae Nielsen, 2009
decticus (Howard, Dyar & Knab, 1917)
detritus (Haliday, 1833)
dorsalis (Meigen, 1830)
dufouri (Hamon, 1953)
duplex (Martini, 1926)
dzeta (Séguy, 1924)
eidsvoldensis (Mackerras, 1927)
euedes (Howard, Dyar & Knab, 1913)
euiris (Dyar, 1922)
excrucians (Walker, 1856)
explorator (Marks, 1964)
fitchii (Felt & Young, 1904)
flavescens (Müller, 1764)
grossbecki (Dyar & Knab, 1906)
gutzevichi (Dubitsky & Deshevykh, 1978)
hakusanensis (Yamaguti & Tamaboko, 1954)
harrisoni (Muspratt, 1953)
hesperonotius (Marks, 1959)
hexodontus (Dyar, 1916)
hodgkini (Marks, 1959)
hokkaidensis (Tanaka, Mizusawa & Saugstad, 1979)
hungaricus (Mihályi, 1955)
imperfectus (Dobrotworsky, 1962)
impiger (Walker, 1848)
    subspecies daisetsuzanus (Tanaka, Mizusawa & Saugstad, 1979)
    subspecies impiger (Walker, 1848)
implicatus (Vockeroth, 1954)
increpitus (Dyar, 1916)
inexpectatus (Bonne-Wepster, 1948)
intermedius (Danilov & Gornostaeva, 1987)
jacobinae (Serafim & Davis, 1933)
kasachstanicus (Gutsevich, 1962)
lasaensis (Meng, 1962)
    subspecies gyirongensis (Ma, 1982)
    subspecies lasaensis (Meng, 1962)
lepidus (Cerqueira & Paraense, 1945)
leucomelas (Meigen, 1804)
linesi (Marks, 1964)
longifilamentus (Su & Zhang, 1988)
luteifemur (Edwards, 1926)
macintoshi (Marks, 1959)
martineti (Senevet, 1937)
melanimon (Dyar, 1924)
mercurator (Dyar, 1920)
milleri (Dyar, 1922)
montchadskyi (Dubitsky, 1968)
nevadensis (Chapman & Barr, 1964)
nigrinus (Eckstein, 1918)
nigripes (Zetterstedt, 1838)
nigrithorax (Macquart, 1847)
nigrocanus (Martini, 1927)
niphadopsis (Dyar & Knab, 1918)
nivalis (Edwards, 1926)
normanensis (Taylor, 1915)
perkinsi (Marks, 1949)
phaecasiatus (Marks, 1964)
pionips (Dyar, 1919)
procax (Skuse, 1889)
pseudonormanensis (Marks, 1949)
pulcritarsis (Rondani, 1872)
    subspecies asiaticus (Edwards, 1926)
    subspecies pulcritarsis (Rondani, 1872)
pullatus (Coquillett, 1904)
punctodes (Dyar, 1922)
punctor (Kirby, 1837)
purpureifemur (Marks, 1959)
ratcliffei (Marks, 1959)
rempeli (Vockeroth, 1954)
riparioides (Su & Zhang, 1987) riparius Dyar & Knab, 1907
sagax (Skuse, 1889)
sallumae (González & Reyes, 2017) (in González et al., 2017)
sapiens (Marks, 1964)
schizopinax (Dyar, 1929)
schtakelbergi (Shingarev, 1928)
scutellalbum (Boshell-Manrique, 1939)
sedaensis (Lei, 1989)
sergievi (Danilov, Markovich & Proskuryakova, 1978)
shannoni (Vargas & Downs, 1950)
silvestris (Dobrotworsky, 1961)
simanini (Gutsevich, 1966)
sinkiangensis (Hsiao, 1977)
spencerii (Theobald, 1901)
    subspecies idahoensis (Theobald, 1903)
    subspecies spencerii (Theobald, 1901)
squamiger (Coquillett, 1902)
sticticus (Meigen, 1838)
stimulans (Walker, 1848)
stramineus (Dubitzky, 1970)
subalbirostris (Klein & Marks, 1960)
surcoufi (Theobald, 1912) (in Surcouf, 1912)
tahoensis (Dyar, 1916)
theobaldi (Taylor, 1914)
thibaulti (Dyar & Knab, 1910)
upatensis (Anduze & Hecht, 1943)
ventrovittis (Dyar, 1916)
vittiger (Skuse, 1889)
washinoi (Lanzaro & Eldridge, 1992)

Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith