Pheidole

Pheidole is a genus of ants, family Formicidae, subfamily Myrmicinae, tribe Attini, established by Westwood in 1839, comprising approximately 1,173 species and commonly called big-headed ants for the disproportionately large heads of their major workers. Many species in the genus first evolved in the Americas, while others, such as Pheidole indica and Pheidole megacephala, originated in East Asia and Africa respectively and have since dispersed globally, with Pheidole megacephala flagged as a particularly problematic invasive species. Widespread and ecologically dominant, most species are dimorphic, with colonies containing minor and major, or soldier, worker castes, and members occupy diverse habitats including rainforests, deserts and grasslands, serving important ecological functions as seed consumers and predators that improve soil nutrient density.