Dufour's gland contents of queens of the slave-making ant Polyergus rufescens and its host species Formica cunicularia

Dufour's gland contents of the queens of the slave-making ant species Polyergus rufescens and its host, Formica cunicularia, were analysed by gas chromatography-mass spectrometry. In P. rufescens, the gland contains a mixture of several esters, one of which, decyl isobutyrate, was consistently present in large quantities (constituting more than 80% of glandular contents). Glandular contents in the host species, were found to be different, containing, in addition to two substances also found in P. rufescens, a mixture of acetates and several hydrocarbons. Decyl isobutyrate was not present. We discuss the possible role of these substances in the life history of P. rufescens.