W-albus Group

Type species: 

Aedes w-albus (Theobald, 1905), original combination: Stegomyia w-alba.


Subfamily Culicinae, genus Aedes, subgenus Stegomyia. The W-albus Group includes 10 species divided between four subgroups, the Annandalei, Desmotes, Mediopunctatus and W-albus Subgroups.


Species of the W-albus Group are distinguished from other species and groups of subgenus Stegomyia by the following combination of characters (adapted principally from Huang, 1977, 1979). ADULTS ‒ Maxillary palpus with pale scaling; ornamentation of scutum varied, species have different patterns of pale patches and longitudinal pale stripes; prescutellar area with or without broad dark scales on either side of bare space; dorsocentral setae absent; scaling of scutellum varied, with broad dark scales on midlobe and broad pale scales on lateral lobes or broad pale scales on midlobe and broad dark scales, or dark and pale scales, on lateral lobes; paratergite with broad pale scales; subspiracular area and postspiracular area with broad pale scales; mid- and hindfemora each with knee spot, absent on forefemur, forefemur dark-scaled anteriorly or with basoventral line of pale scales, midfemur with or without anterior pale spot near mid-length; anterior surface of hindtibia entirely dark-scaled or with long basoventral basal pale stripe; hindtarsomeres 1 and 2 with basal pale bands, hindtarsomere 3 with or without basal pale band, hindtarsomere 3 entirely dark-scaled, hindtarsomeres 4 and 5 all pale, all dark or with basal pale bands; both ungues of fore- and midlegs toothed in both sexes, equal in females, unequal in males. FEMALE GENITALIA – Caudal margin of sternum VIII with a deep median U-shaped notch; tergum IX varied, slightly to much broader than long to slightly longer than broad, with well-developed posterolateral lobes, each with 3‒6 setae. MALE GENITALIA ‒ Caudal margin of tergum IX concave, more or less straight or produced as a large lobe; gonostylussimple and elongate or complex with swollen based and bifurcated distally; gonostylar claw spiniform; paraproct with or without ventral arms. LARVAE ‒ Comb plate present or absent, comb scales borne in a single row; saddle with inconspicuous or long stout spicules on posterior margin; ventral bush (seta 4-X) with 4 pairs of setae. PUPAE ‒ Paddle with fringe of filiform spicules on inner and outer margins, apex evenly rounded or produced, seta 1-Pa single. See subgenus Stegomyia.

Phylogenetic relationships: 

The W-albus Group comprises a complex and highly variable collection of species, and without a thorough review of subgenus Stegomyia it is not currently possible to determine the affinities of the group.

Bionomics and disease relations: 

The immature stages of species of the W-albus Group are mainly found in bamboo stumps, bamboo internodes, cut and split bamboo, bamboo cups, tree holes and log holes, and axils of Nipa palms and Pandanus. Rattanarithikul et al. (2010) noted that larvae of Ae. gardnerii imitator and Ae. w-albus have been found in banana stumps/axils and artificial containers, respectively, in Thailand. Females of Ae. annandalei, Ae. craggi (Annandalei Subgroup), Ae. desmotes (Desmotes Subgroup), Ae. mediopunctatus, Ae. perplexus (Mediopunctatus Subgroup), Ae. gardnerii imitator and Ae. w-albus (W-albus Subgroup) are known to bite humans.

Species of the W-albus Group are not known to transmit pathogens to humans, but are considered to be of potential health importance.


Species of the W-albus Group are distributed in the Oriental Region.

Principal references: 

Huang, 1977 (description, distribution, bionomics, keys to adults, pupae and larvae); Huang, 1979 (Oriental Region, keys); Rattanarithikul et al., 2010 (as species of genus Stegomyia, distributions, bionomics, keys for identification of adults and larvae).

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