The relationship between queen execution and cuticular hydrocarbons in stingless bee Melipona scutellaris (Hymenoptera: Meliponini)

Abstract

In queenright colonies of stingless bees of the genus Melipona, workers recognize, attack, and kill young virgin queens. For Melipona scutellaris, we observed that virgin queens were executed when they were between 5 and 9 days old, while newly emerged queens were not attacked. The faster movements of old virgin in relation to newly emerged might be responsible for attacks. It has been also hypothesized that cuticular hydrocarbons are the source of the signal used by workers to recognize virgin queens. We investigated whether newly emerged, 8 days old virgin and physogastric queens of M. scutellaris have different cuticular hydrocarbon profiles. Cuticular hydrocarbons of three ages were compared using gas chromatography-mass spectrometry. The cuticular hydrocarbon profiles varied by reproductive status and age. Changes in the cuticular hydrocarbons in virgin queens during aging suggest that these compounds, together with change in movement, may play a role in the recognition of virgin queens by workers prior to regicide.