The genus Pogonomyrmex contains more than 70 species [1]. These ants are found only in the western hemisphere, from the very southernmost tip of South America, up into southern Canada. Two species are found in Haiti/Dominican Republic [2]. There are 25 species in North America, north of Mexico - all of which are found west of the Mississippi, with the exception of one - P. badius (the Florida harvester) [3]. The name Pogonomyrmex is often shortened to 'Pogo'

Referred to as 'harvester ants' (along with many other species in various genera), Pogos are among the most well known and conspicuous members of the arid-land ant fauna. They can play an important role in the shaping of plant communities in the surrounding environment, due to their seed harvesting and seed dispersing behaviors. Some species remove the vegetation from the immediate area surrounding their nest-mounds as well - resulting in large clearings [4].

Many Pogos can be quite aggressive, and will sting readily in defense of the nest, and themselves. The nest-mounds of some species are large (often more than .3m/1 ft tall) conical or dome-shaped structures, in many cases covered with fine gravel.

Gustav Mayr (Austrian entomologist 1830-1908) named and described the genus in 1868. The name means ' bearded ant', and is a reference to the psammophore (a sand-carrying structure) that many Pogos possess.

Pogos are part of the subfamily Myrmicinae, which is the largest subfamily of ants (Hymenoptera: Formicidae) in the world. [scroll down for additional notes/references]

ADDITIONAL NOTES/REFERENCES:

[1]
·Antweb.org - hosted by The California Academy of Sciences
·Lattke, J.E. 2006. A New Species of Pogonomyrmex
(Hymenoptera: Formicidae) from Gallery Forests of the Orinoco Watershed, Venezuela. Myrmecologische Nachrichten, 8, 53-57, Wien, September 2006
·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press.

[2]
·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press.

[3]
·Cole, A.C. 1968. Pogonomyrmex Harvester Ants: A Study of the Genus in North America. Knoxville, University of Tennessee Press
·Fisher, B.L. & S.P. Cover. 2007. Ants of North America: A Guide to the Genera. Berkeley and Los Angeles, CA, University of California Press

[4]
Many Pogonomyrmex species can have a significant influence on the structure of plant communities and ecosystems. Their seed harvesting habits can have the effect of removing large amounts of viable seeds, but this can be offset by the dispersal of seeds that are dropped during transport, seeds that sprout in shallow granaries within the ants' nests, or are discarded in ant nest middens (where they often grow with vigor). Pogos harvest many different types of seeds, so the diversity and composition of certain plant species near the nest is often affected greatly (in many cases, allowing alternate species to thrive, by harvesting the viable seeds of a usually dominant species). The nest mounds themselves contain higher levels of nutrients than surrounding soils, and serve as fertile ground - encouraging plant growth (especially after the nest is abandoned by the ants). The cleared areas around many Pogo nests can also have a dramatic effect on surrounding ecosystems, especially when Pogo nest density is high.

·Hölldobler, B. & E.O. Wilson.1990. The Ants. Cambridge, MA, Belknap/Harvard Press
·Rico-Gray, V. & Oliveira, P.S. 2007. The Ecology and Evolution of Ant-Plant Interactions. University of Chicago Press, Interspecific Interactions Series, Chicago and London (and references contained therein - especially MacMahon, Mull, and Crist, 2000)
·Soul
é, P.T. & P.A. Knapp. 1996. Pogonomyrmex owyheei Nest Site Density and Size on a Minimally Impacted Site in Central Oregon. Great Basin Naturalist 56(2), 1996, pp. 162-166