Abstract:
BACKGROUND : A century of studies have described particular aspects of relatively few mosquito species in southern
Africa, mostly those species involved with disease transmission, specifically malaria and arboviruses. Patterns of
community composition such as mosquito abundance and species diversity are often useful measures for medical
entomologists to guide broader insights and projections regarding disease dynamics and potential introduction,
spread or maintenance of globally spreading pathogens. However, little research has addressed these indicators in
southern Africa.
RESULTS : We collected 7882 mosquitoes from net and light traps at 11 localities comprising 66 species in 8 genera.
We collected an additional 8 species using supplementary collection techniques such as larval sampling, sweep-netting
and indoor pyrethrum knockdown catches. Highest diversity and species richness was found in the Okavango Delta of
Botswana and in South Africa’s Kruger National Park, while the lowest diversity and abundances were in the extreme
southern tip of South Africa and in semi-desert Kalahari close to the South Africa border with Botswana. Species
composition was more similar between proximal localities than distant ones (Linear model P-value = 0.005). Multiple
arbovirus vector species were detected in all localities we surveyed (proportion of vector mosquito numbers were > 0.
5 in all locations except Shingwedzi). Their proportions were highest (> 90%) in Vilankulo and Kogelberg.
CONCLUSIONS : Multiple known arbovirus vector species were found in all study sites, whereas anopheline human malaria
vector species in only some sites. The combination of net traps and light traps effectively sampled mosquito species
attracted to carbon-dioxide or light, accounting for 89% of the 74 species collected. The 11% remaining species were
collected using supplementary collection techniques mentioned above. The diversity of species weas highest in savanna
type habitats, whereas low diversities were found in the drier Kalahari sands regions and the southern Cape fynbos
regions.