[2] Approximately 70 species are currently recognized as belonging to this genus, most of which are distributed in the Old World tropics and subtropics, but a few of which occur in the temperate zone.

Some species are also found widely separated in North America and the Pacific Islands, as a result of human introduction.

[3] Several species of this genus have a striking male polymorphism, with both winged and wingless forms.

The worker ants, sisters of these queens, may transport the queens several meters from their natal nest and drop them off at another, alien nest to promote outbreeding with wingless stationary males in a process somewhat analogous to third party matchmaking in humans.

[5] After mating during the winter, the sexual females may depart in the spring and find their own colonies.