L. Passera et al., ELIMINATION OF SEXUAL BROOD IN THE ARGENTINE ANT LINEPITHEMA HUMILE -QUEEN EFFECT AND BROOD RECOGNITION, Entomologia experimentalis et applicata, 75(3), 1995, pp. 203-212
Mated queens of the ant Linepithema humile (Iridomyrmex humilis Mayr)
introduced into dequeened colony fragments rearing sexual brood elicit
ed worker aggression resulting in queen larvae being bitten and elimin
ated. By contrast, male larvae were spared. Regarding queen brood, kil
ling mainly concerned small and medium sized larvae. A large proportio
n of the large larvae escaped extermination, and prepupae and pupae we
re spared. These data suggest that workers were able to discriminate s
ex, caste and age of the brood. That a queen pheromone may be involved
was shown by experiments using whole or cut corpses that were either
rinsed or not rinsed in pentane. The pheromone eliciting worker aggres
sive behaviour was shown to act over a short distance, suggesting that
it is somewhat volatile. Similarities and differences between this ne
w queen pheromone and other known queen pheromones acting on queen pro
duction or worker attraction are discussed as well as the origin of th
e signals underlying the recognition of the larval classes.