Behavior of Workers of Solenopsis invicta (Hymenoptera: Formicidae) to the Queen Recognition Pheromone: Laboratory Studies with an Olfactometer and Surrogate Queens1

Abstract

Red imported fire ant (RIFA), Solenopsis invicta Buren, queens produce a queen recognition pheromone that attracts daughter or conspecific worker ants singly or in groups. Their attractiveness ceases if they are separated from their colony for more than 30 min, but returns immediately when they are reunited with their workers. Whole-body queen extracts of the pheromone are attractive when carried by an air stream into an olfactometer or when applied to surrogate queens (pieces of rubber septa). Extracts of the pheromone induce some attraction at a concentration of 0.01 queen equivalent, with maximum response at concentrations of 0.5 to 5.0 queen equivalents. The response of workers to extracts of other RIFA castes was significantly less than that to queen extracts in all bioassays.