Biogeography, Diversity and Ecology of Sawflies in the Afromontane Region (Insecta: Symphyta)

Abstract

In the Afrotropical region the sawfly fauna is, in comparison with other biogeographical regions, except Australia, very poor both in number of species and number of individuals. The Afromontane region is composed of a series of archipelago-like disjunctions. This is especially true for eastern and south-eastern Africa, where these consist of regional mountain systems with specific abiotic factors, and it seems that the mountain-specific sawfly diversity, with its many endemic species, is unique and dependent on the mountain systems’ genesis. Species of the Athalia vollenhoveni-group are known only from the Afrotropical region. The species of this group seem to prefer the montane and sub-montane region and have more narrow ranges than previously thought. The sawfly diversities of different habitats of four mountain systems in the Drakensberg district, South Africa, were investigated over a two-year period. In total 27 species were recognized, including at least 13 species new to science. Furthermore, a minimum of seven species are endemic to vegetational types of the Drakensberg. Only very few species are widely distributed and can be regarded as eurytopic, because these species occur from the lowlands up to the mountains.