Cuticular hydrocarbon profiles correlate with caste, sex, and polyethism in the stingless bee Melipona solani (Hymenoptera: Meliponini)

Information exchange and nestmate recognition among workers of highly social insects are tasks that usually involve cuticular hydrocarbons (CHCs). Many studies in stingless bees have shown that CHCs carry information about nest origin, age, caste, sex, reproductive status, and their function in the colony. Thus, in this work, we characterised the CHC composition of queens, gynes, drones, and workers of Melipona solani by gas chromatography coupled to mass spectrometry. Any possible age-related difference was investigated by analysing the CHC profile of workers of different ages. We found quantitative and qualitative differences in the CHC composition between castes (workers and queens), and among drones, gynes, and queens. Similarly, polyethism (age of workers) correlated with CHCs, which allowed the separation of three groups: (i) foragers/guards; (ii) nurses; and (iii) larvae, pupae, and recently emerged workers. We discuss the possible function of these compounds in the stingless bees’ recognition interactions.