Pogonomyrmex

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iPogonomyrmex

Scientific classification

Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Myrmicinae
Tribe:	Myrmicini
Genus:	Pogonomyrmex

Species and Subspecies

71 species and subspecies

Pogonomyrmex is a genus of harvester ants, occurring primarily in the deserts of North America. They have the most toxic venom documented in any insects, with Pogonomyrmex maricopa being the most toxic tested thus far. It has an LD50 of only 0.12 mg/kg, compared to honeybee venom, at 2.8 mg/kg, and comparable to cobra venom (there are, in fact, only about a dozen recorded LD50 values for snakes which are lower than 0.12, mostly seasnakes). This venom is presumed to be an anti-vertebrate defense, specifically against predators that have evolved to selectively feed on them, most notably horned lizards. Note, however, that the actual amount injected by a single ant is incredibly small, and they pose no actual threat to humans or other animals. Note that very few insects have had the toxicity of their venoms formally tested, and it is likely that other insects have more potent venoms (e.g., the venom of Lonomia, which can kill humans).

These ants dig very deep nests with many underground chambers in which they keep seeds, from which they derive food for their larvae. The areas around Pogonomyrmex nests tend to be utterly devoid of vegetation, and are easily seen from a distance. In addition to horned lizards, there are predatory wasps in the genus Clypeadon which feed only on Pogonomyrmex workers, paralyzing them with their venom, and then carrying them back to a burrow where they will serve as food for the wasp's larva.