The black harvester ant, Pogonomyrmex rugosus (Emery) is also often called the rough harvester ant. The workers of this species are dark colored, usually black or reddish black. These ants are found from California to western Texas.
Black harvester ants, like most other harvester ants, have a “beard”. There is a small tuft of hairs on the underside of the ant's head. Scientists call this the psammophore. The ants use these hairs to clean their legs and their antennae. They also use the hairs to help carry sand or soil particles while they are digging.
Black harvester ants are ground-nesting ants. The workers make a mound that is round and rather flat on top. There can be several openings on the sides of the mound. There is usually a clearing around the mound.
The black harvester ant workers gather seeds. These ants are among the principal seed gatherers in the desert of the southwestern United States. The ants are able to compete with mice and other mammals for the seeds they need. The harvester ant workers are also predators of insects.
Black harvester ants are very aggressive, especially when their nest is disturbed. The workers can deliver a painful sting. Some people think that the sting of the black harvester ant might be the most painful insect sting in North America. People who are allergic to insect stings should be very careful when they are near black harvester ant nests.