THE GIANT NESTS OF THE AFRICAN STINK ANT PALTOTHYREUS-TARSATUS (FORMICIDAE,PONERINAE)

Fourteen nests of the ponerine ant Paltothyreus tarsatus were excavated in Kenya and in the Ivory Coast. All colonies contained only one mated queen. The worker population varied markedly between colonies, reaching 2444 adults in one case. Nests consisted of many chambers located 30 cm to more than 150 cm below the surface. The construction and arrangement of the chambers were not particularly elaborate, but the associated horizontal tunnel system (5-15 cm below the surface) was most remarkable. In one nest, over 130 m of shallow subterranean tunnels were uncovered. An area of 1200 m2 was covered by the tunnel system of another nest. Through multiple tunnel exits the ants are able to reach almost any spot in their foraging area. In some nests we found a second horizontal tunnel system, 50-80 cm below the surface, which connected nest chambers several meters apart.