[Chemical strategy during foraging in Solenopsis fugax Latr. and Monomorium pharaonis L.]

1. Solenopsis fugax, a subterranean ant, lays odorous trails in the tunnels leading to the brood chambers of neighbouring ant species. The recruitment trail pheromone originates from the Dufour's gland. 2. In addition, when preying on the foreign brood, Solenopsis fugax discharges a highly effective and long lasting repellent substance from the poison gland. This prevents the brood keeping ants from defending their own larvae against the predators. 3. A very similar chemical foraging strategy is used by Monomorium pharaonis. A repellent substance enabling Monomorium to compete successfully with other ant species for food sources is discharged. The recruitment pheromone originates from the Dufour's gland; a repellent substance enabling Monomorium to compete successfully with other ant species is discharged from the poison gland.