Solenopsis

also known as Fire Ants because of the intense, burning sensation caused by their stings.

Solenopsis is a large, cosmopolitan, and taxonomically difficult genus of mostly minute, monomorphic, wholly subterranean species. These minute species frequently live as thief ants within the colonies of other larger species of ants or termites.

Some New World species are larger and the workers are polymorphic. These species have colonies that can be very large and the workers are aggressive surface foragers.