A Field Guide to the Prairie

Argentine ant

Argentine Ant
Iridomyrmex humilis
Length: 2.5-3 mm
Habitat/Range: Native to Argentina. The first ants were accidentally introduced from boats coming from South America. Common throughout the southeast and southern California. These ants will nest in soil and mulch, as well as under stones, logs, and debris. They are often found in tree holes, bird nests, leaf litter, and beehives.

Argentine ants are small brown ants with a single node in the waist. They are typically found travelling in well-defined trails between nests and food sources. Argentine ants may be one of the few ants whose colonies don't fight. Each ant knows it belongs to a distinctive colony, but will not fight an argentine ant from another colony. However, they terrorize the rest of the insect world, often eliminated every other type of ant species in an area. They are determined pests, especially in California, where residents' foodstuffs are devoured by these ants. Argentine Ants can even get into jars that have screw top lids.

On the Prairie Field Guide Index

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