Pogonomyrmex californicus worker.

Though it is found in several states in the western US (and in parts of Mexico), this orangish-red Pogo is referred to as 'the California harvester'.

Typical length of worker ranges from 5.5mm to 8.7mm [Taber 1998]. As is the case with most Pogos, the color of these ants can be variable - typical coloration is all red, all orange-red, or all brownish-red. In many cases however, these ants are red (as mentioned above), but with a much darker colored gaster (rearmost abdominal body part), making for a distinctly bi-colored ant. In areas where ranges overlap, it is sometimes very difficult to differentiate the all-red variety of Pogonomyrmex californicus from P. maricopa.

The nests of this Pogo usually take the form of low, semicircular (or circular) sand craters. In addition to the typical crater nests, we have observed P.californicus (in northern Nevada) nesting under tumbleweed (Salsola sp.), with no crater, and a single well-hidden entrance. P.californicus colonies have been known to contain 4500 ants. The workers of this species forage individually, and recruit nestmates to food sources.

The US range of this ant includes parts of Arizona, California, Nevada, New Mexico, extreme southeastern Oregon, Texas, and Utah. In Mexico, it is found in Baja California, Chihuahua, and Sonora.

[IMAGE: Pogonomyrmex californicus worker - northern Nevada, USA] [scroll down for additional notes/references]

ADDITIONAL NOTES/REFERENCES:

·Cole, A.C. 1966. Ants of the Nevada Test Site. Brigham Young University Science Bulletin, Biological Series - Vol. VII, Number 3, June 1966
·Cole, A.C. 1968. Pogonomyrmex Harvester Ants: A Study of the Genus in North America. Knoxville, University of Tennessee Press
·Johnson, R.A. 2000. Seed Harvesting Ants (Hymenoptera: Formicidae) of North America: An Overview of Ecology and Biogeography. Sociobiology Vol.36, No. 1, 2000
·Taber, S.W. 1998. The World of the Harvester Ants. College Station, TX, Texas A&M University Press