[[Genus Trachymyrmex ^HNS ]]

Trachymyrmex ^HNS is the most species-rich and abundant attine genus in the United States, reaching its highest diversity in the arid Southwest, particularly in Arizona. Trachymyrmex ^HNS is a primarily tropical genus; most species are found in Central and South America. Only a handful of species have radiated north into the temperate zone and these are biologically very interesting. Some North American species are notably cold-tolerant. For example, T septentrionalis ^HNS reaches the northern limit of its geographic range on Long Island, NY, and at this latitude, has a short active season of only four to five months per year (Beshers & Traniello 1994). During winter, the ants and the fungus garden enter extended dormancy, a phenomenon unique among the Attini ^HNS (Weber 1956).