Ant species richness along a climatic gradient in the Namib Desert

Twenty-seven ant species belonging to two subfamilies, the Myrmicinae (22 species) and the Formicinae (5 species) were collected in pitfall traps along a 100 km long transect traversing the width of the central Namib Desert. Ant species richness across the desert was strongly correlated with mean annual rainfall, an index of primary productivity. The majority of Namib Desert ants were either granivorous or honeydew–nectar feeders, the remainder being either insectivores or omnivores. The occurrence of only two subfamilies in the Namib Desert is in part attributable to the abilities of certain members of these ant groups to store food.