Formica-parasite
Guides
Polyergus mexicanus
Western Amazon Ant
Polyergus mexicanus is an obligate social parasite known as the Western Amazon Ant, widely distributed across western North America. This species is incapable of performing basic colony tasks including foraging, nest excavation, and brood care, and depends entirely on enslaved workers of Formica host species. The species performs dramatic, coordinated raids on Formica colonies to capture larvae and pupae, which are then integrated into the parasite colony. Recent genetic studies have revealed substantial population structure associated with different host species, suggesting incipient speciation into host-specific lineages.