Identification of oxygen containing volatiles in cephalic secretions of workers of Brazilian stingless bees

The volatile constituents of cephalic secrections of 11 Brazilian social st ingless bee species of the Tetragonisca - Tetragona line have been analysed . By gas chromatography/ mass spectrometry 145 compounds could be identifie d which include 72 esters, 22 alcohols, 16 carboxylic acids, 13 terpenoids, 8 aldehydes, 7 ketones, 4 aromatic compounds, 2 lactones and 1 dihydropyra n. Structural relations, origin, and distribution of these compounds are di scussed. With respect to qualitative and quantitative composition, each spe cies shows a specific odour pattern which is made up by less specific compo nents. To a certain extent, closely related species show some similarities in the odour bouquets. The mass spectrometric fragmentation patterns of typical wax type esters an d DMDS derivatives of unsaturated esters are discussed in detail.