A desert leafcutter, Acromyrmex versicolor, carrying a leaf back to her nest. Tucson, Arizona, USA
Male leaf-cutting ants (Acromyrmex versicolor) lek above the desert floor, awaiting virgin queens who fly into the swarm to mate. This species flies during the Arizona summer monsoon season, early in the morning after a soaking rain. Tucson, Arizona, USA
After mating, a young leafcutter ant queen sheds her wings. Acromyrmex versicolor. Tucson, Arizona, USA
Novomessor cockerelli
Harvester ants (Novomessor cockerelli) tear apart a queen leafcutter ant (Acromyrmex versicolor) they have caught after a leafcutter mating flight. Ants won't often eat members of their own species, but they will happily consume ants of other species. Tucson, Arizona, USA
Acromyrmex versicolor desert leafcutter ant nest in an urban setting. Green Valley, Arizona, USA
Novomessor cockerelli, one of the most conspicuous harvester ants of American southwest, carries a mesquite seed back to her nest. Tucson, Arizona, USA
Novomessor cockerelli, guarding the nest. Tucson, Arizona, USA
Novomessor albisetosa
Novomessor albisetosa harvester ants carry a seed back to their nest. Portal, Arizona, USA
Pogonomyrmex maricopa & Novomessor albisetosa
Pogonomyrmex maricopa and Novomessor albisetosa workers, fighting. Resources are scarce in the desert and competition among ants is fierce, leading to frequent conflicts. Green Valley, Arizona, USA
The mass emergence of termites at the start of monsoon season is a bonanza for ants. Here, a Novomessor albisetosa harvester ant adds another captured termite carcass to the food pile. Peña Blanca Lake, Arizona, USA
Camponotus ulcerosus major worker, showing the enlarged head she uses for plugging the nest entrance. Sierra Vista, Arizona, USA
A young Camponotus festinatus queen scales a grass blade to launch herself on a nocturnal mating flight. Tucson, Arizona, USA
Camponotus semitestaceus Mojave National Preserve, California, USA
Camponotus ocreatus, with pupae Portal, Arizona, USA
Major and minor workers of Cephalotes rohweri, the Arizona turtle ant. Tucson, Arizona, USA
Cephalotes rohweri, the Arizona turtle ant. Tucson, Arizona, USA
Syscia augustae
Syscia augustae, a blind subterranean insect, is one of the least known North America ant species. It occurs in the desert southwest. Portal, Arizona, USA
Cyphomyrmex wheeleri is the most temperate of the Cyphomyrmex species, occurring as far north as San Francisco, California. Here worker ants tend to their fungus garden. Austin, Texas, USA
Sonoran desert cacti are frequently covered in ants. Cacti provide ants with nectar- a ready food supply in a harsh environment- in exchange for protection from herbivorous insects. Here, two Crematogaster opuntiae acrobat ants exchange nectar they have gathered from a chain-link cholla. Tucson, Arizona, USA
Dorymyrmex bicolor workers scavenge the carcass of a harvester ant. Willcox, Arizona, USA.
An alate Dorymyrmex insanus queen climbs a stick of grass to gain an altitudinal head start before departing on her mating flight. Tucson, Arizona, USA
Male and female Forelius mccooki in the nest. Tucson, Arizona, USA
Forelius mccooki workers taking nectar from a Cholla cactus in the Sonoran desert. Cacti provide nectar to attract ants, as some ant species help the plant by removing herbivorous insects. Tucson, Arizona, USA
Early morning sun catches a mating flight of Forelius mccooki in the Sonoran desert. Tucson, Arizona, USA
Veromessor lariversi
A worker harvester ant carrying a seed back to her nest. Night-active species are often lighter in color than their day-active counterparts. Sand Springs Dune, Nevada, USA
Veromessor pergandei
Veromessor pergandei is among the most commonly seen seed harvesting ants in southern California. Colonies of this species contain worker ants of different sizes, while most other seed harvesters in the region have monomorphic workers. Here, a major worker carries a seed back to the nest. Anza Borrego Desert, California, USA
Black harvester ants carrying seeds back to the nest. Mojave National Preserve, California, USA
A nest of black harvester ants, Veromessor pergandei. Mojave National Preserve, California, USA
The distinctive nest entrance of the nocturnal honeypot ant Myrmecocystus mexicanus. Huachuca mountains, Arizona, USA
Myrmecocystus honeypot ant species come in three basic color patterns, depending on the time of day that they forage. The orange/yellow species such as this M. navajo are nocturnal. These ants were photographed leaving their nest entrance to forage shortly after dusk. Willcox, Arizona, USA
Myrmecocystus tenuinodis, a small honeypot species that lives in sand dunes and is active in the mornings. Mojave National Preserve, California, USA
Myrmecocystus mimicus worker leaving the nest to forage. Sycamore Canyon, Arizona, USA
Myrmecocystus mexicanus. Honeypot ants have an unusual food storage system. Some members of each colony act as living receptacles known as "repletes", these ants become engorged with food and hang from the ceilings of chambers deep underground. Captive colony at the California Academy of Sciences
Myrmecocystus mendax honeypot ant, with pupae. Chiricahua mountains, Arizona, USA
Army ant males are most commonly seen at night. They sometimes end up at lights as they disperse on wing from their natal colonies. This army ant, Neivamyrmex swainsonii, is a broadly-distributed species found from the southern United States to northern Argentina. Peña Blanca Lake, Arizona, USA
A raiding column of Neivamyrmex nigrescens. Huachuca Mountains, Arizona, USA
Odontomachus clarus, the desert trap-jaw ant. Portal, Arizona, USA
A trail of Pheidole rhea, North America's largest Pheidole species. Tucson, Arizona, USA