Novel internally branched, internal alkenes as major components of the cuticular hydrocarbons of the primitive australian antNothomyrmecia macrops Clark (Hymenoptera: Formicidae).

Internally mono- and dimethyl branched, internal alkenes, which constitute most of the cuticular hydrocarbon present on workers of the primitive Australian antNothomyrmecia macrops Clark, have been identified by gas chromatography-mass spectrometry. They are the first such alkenes reported from insects. Also present are alkanes with similar carbon skeletons. The hydrocarbon patterns of three separateNothomyrmecia colonies were very similar.