A Comparative Overview of Flower Visiting by Non-Apis Bees in the Semi-arid to Arid Areas of Southern Africa

Abstract

A comparative overview of flower visiting by non-Apis bees in the semi-arid to arid areas of southern Africa is presented. This is based on a survey of non-Apis bees and aculeate wasps in these areas. Flower visiting records (16,229) were assembled for 420 species of bees, 375 species of non-masarine wasps and 129 species of masarine wasps. Thirty six plant families were included. Of these 34 were visited by non-Apis bees, 28 by non-masarine wasps, and 22 by masarine wasps. In decreasing order, the ten families which received visits from the highest percentages of species of bees are: Fabaceae, Asteraceae, Aizoaceae, Zygophyllaceae, Lamiaceae, Malvaceae, Acanthaceae, Boraginaceae, Scrophulariaceae, and Brassicaceae. Most bee species visiting Fabaceae visit Papilionoideae unlike wasps, of which most visiting Fabaceae visit Mimosoideae. In the analysis bees overall show a high diversity of flower family choice at the specific level similar to that of non-masarine wasps. All bee families show a range from oligophagy or from narrow polyphagy to relatively broad polyphagy. No species are indiscriminately polyphagous. Two bee families, Colletidae and Melittidae, show a diversity of choice at the specific level lower than that of the other bee families and similar to that shown by masarine wasps. This suggests, for these two families, a relatively high incidence of oligophagy equivalent to that shown by Masarinae.