Red Harvester Ant
Pogonomyrmex barbatus
This colony of likely Red Harvester Ants (P. barbatus) was photographed in Haunted Canyon at the eastern edge of the Superstition Mountains, Gila Co., Arizona.
Formicidae -- Ant Family
Large (ca. 10 mm) conspicuous, occasionally aggressive ants that can sting fiercly if disturbed. An area 1 to 3 m in diameter around the nest entrance is cleared of all plant debris and small stones. The mound is usually not elevated but just beyond the cleared area a heap of empty seed hulls often accumulates. Nests may survive for a decade or more so that a significant heap of composting debris develops.
Young Pogonomyrmex ants have tough, sharp mandibles that can cut open tough seed hulls, thus they remain inside the nest as seed crackers. Eventually the mandibles become dulled from this work and the aging ants graduate to outside collecting duties. Seeds form the bulk of the ants' diet, but they also forage for dead or dying insects or any other food they can find. Harvester ants can deliver a painful sting, but normally are not particularly aggresive. To remain standing directly in a harvester ant nest clearing is ill-advised. The venom is reportedly among the most toxic.
More Information:
- Bugguide.net Univ. of Iowa
- Ants of the Southwest
- Myrmecos.net
- Google Images
- Google Scholar Literature Search
- Book Reference: Venomous Animals of Arizona by Robert Smith (who was one of my profs at U.A.) available at Abe Books.