PYGIDIAL GLAND OF AZTECA NR. BICOLOR AND AZTECA CHARTIFEX - MORPHOLOGY AND CHEMICAL-IDENTIFICATION OF VOLATILE COMPONENTS

The large paired reservoirs of the pygidial gland of Azteca nr. bicolo r and A. chartifex represents the largest exocrine structure in the ab domen. The glands produce a secretion with a strong smell, which the a nts release when they are disturbed. Analyses of the secretions by gas chromatography-mass spectrometry (GC-MS) revealed a mixture of iridoi ds and ketones. A. nr. bicolor contains 2-heptanone (8%) and a mixture of three iridodial isomers, with trans-trans-iridodial as the major c omponent (32%). A. chartifex contains 6-methyl-5-hepten-2-one (13%) an d the three isomeric iridodials with cis-trans-iridodial as the princi pal component (32%).