These outlines have been compiled from the published literature, mostly of the last twenty five years. They are intended simply as guides to the most useful articles for those who have little knowledge of the subject. In cases where an author has reviewed several papers and given a general account of the epidemiology, this key reference only is given, as previous authors will be cited therein. References to abstracts in the Review of Applied Entomology or Tropical Diseases Bulletin are given in some cases where an article may not be easily obtainable or may be too long for general reading.
Amongst the species considered here, vittatus is the only one which normally breeds in pools, and these are generally rock pools. Both demeilloni and strelitziae usually breed in the axils of two particular plants and the remaining breed in the rain water which collects in rot holes or crevices of trees, discarded tins, or broken bottles. The more domestic species aegypti and simpsoni breed also in water tanks, troughs, sagging roof gutters etc. or anything similar where water may collect. Larvae of these latter two species, and those of demeilloni and strelitziae are sometimes found in the leaf axils of cultivated banana plants, but it would appear that this depends on these plants being in close proximity to their usual breeding places. The breeding place of pseudonigeria is the only one not known, but it seems probable that it is tree holes. For exceptional breeding places and other details see under the individual species.
Adults are recognized by their sooty black colour, sometimes with bronzy sheen, unspeckled wings, and conspicuous white and sometimes yellow marking. There are white basal bands on at least the first two tarsal segments of the hind legs, and broad or narrow bands on some of the other tarsal segments, which may also be all, or nearly all, white. On most, there is a pair of large sub-lateral white patches on the anterior half of scutum, but exceptions to the latter ornamentation are unilineatus and vittatus.
Determination. This important yellow fever vector is not likely to be confused with any other species. The scutal ornamentation of both sexes is quite characteristic (plate 5) consisting of a pair of narrow crescent shaped sub-lateral white marks on the front half of the scutum, from behind each of which runs a narrow white line to the posterior edge. In the middle of the scutum there is a pair of white lines running from the anterior white patch to about two thirds; there is then a short median white line and white scales bordering the front sides of the prescutellar bare space. Other features not found in any stegomyias of southern Africa are that the middle femora have white stripes in front, from base to near tip, and the clypeus of the female has two patches of white scales (above).
The grouping into faunal areas of the Ethiopian zoo-geographical region of Africa has been based chiefly on that used by Chapin (1932) in his work on the birds of the Belgian Congo. The region includes most of the African continent south of the Tropic of Cancer. Edwards (1941) showed that these divisions can also be applied to the distribution of the Culicidae. Further details concerning the Anophelini have been added by De Meillon (1947); Mattingly (1952 and 1953a) has correlated considerable data relating to the sub-genus Stegomyia, with additional notes (1953b and 1954) and with Bruce-Chwatt as co-author (1954).