Genus Pheidole - Big-headed Ants

formerly in Pheidolini

Greek pheid- 'sparing', 'thrifty'(1), or more exactly pheidole 'thriftiness', 'grudging use'

74 described spp. in our area(2) and >1000 worldwide + perhaps that many or more undescribed; the most abundant and diverse ants of the New World(3)

Species are relatively few in northern states, more diverse in the Southeast, and especially rich in the desert Southwest.

minors 1.5-4 mm, majors 2-5 mm, supermajors of P. rhea 8 mm

Nearly indistinguishable from small Aphaenogaster workers, but the latter never have big-headed majors, and none are as small as most Pheidole.

cosmopolitan, but particularly diverse in the tropics(4); in the New World, n. US to Argentina(3)

Some species are seed harvesters(4), many are generalist predators/scavengers

This is probably the largest genus of ants in the world, possibly rivaled only by Camponotus, both with an unknown number, but easily over 1000 species. They have pronounced worker caste dimorphism, especially in seed harvesting species; major workers are larger than minors and have disproportionately large heads. A few species have an even larger supermajor caste, and are thus trimorphic. Scavenger predators are usually less strongly dimorphic, and longer legged than the seed harvesters.