Revealing the Function of the Cephalic Secretions of the Bee Trigona fulviventris Guerin (Hymenoptera: Apidae)

Stingless bees carry out efficient chemical communication mediated by volatiles, which they produce mainly in the labial and mandibular glands in the head. In this study, we evaluated the behavioral and electrophysiological response of the stingless bee Trigona fulviventris to its cephalic volatiles. We performed field bioassays to assess the effects of cephalic extract, labial gland extract, and mandibular gland extract on worker behavior. In addition, we evaluated the electroantennographic (EAG) response to the extracts. Later, we analyzed the extracts using gas chromatography-mass spectrometry (GC-MS). In no-choice bioassays, the bees showed defensive behavior when exposed to extracts of the head and mandibular glands. In the double-choice bioassays, we observed that the bees were attracted to food sources marked with the extract from the labial gland. We identified nerol, citral, and 2-heptanol as the main components of the mandibular gland. In contrast, octyl hexanoate was the main component of the labial gland. The bees exhibit antennal responses to the extracts and individual compounds.