Aphaenogaster is a genus of myrmicine ants. About 200 species have been described, including 18 fossil species. They occur worldwide except from South America and Southern Africa. They are often confused with Pheidole or Pheidologeton. These two have major and minor workers, while Aphaenogaster has only a single worker caste. Pheidole has three-segmented clubs on its antennae, while Aphaenogaster has four segments and a larger body size. Pheidologeton has 11-segmented antennae, while the antennae in Aphaenogaster are 12-segmented.