Fig. 2.
Chemistry of the Rilaena secretion. a Gas chromatographic profile of a jet droplet from a female specimen, extracted from a secretion-loaded filter paper piece, and assumingly representing the full scent gland secretion of R. triangularis. The profile exhibits five components: 1,4-benzoquinone (peak A), octanoic acid (peak B), unknown I (peak C), unknown II (peak D), and 1,4-naphthoquinone (peak E). Compounds x 1 and x 2 originate from the filter paper. b Profile of a whole body extract of a female specimen, showing all five peaks A–E from its putative scent gland secretion in a first chromatographic zone, and a number of cuticular hydrocarbons in a second chromatographic zone. Major hydrocarbons C21 (n-heneicosane), C23 (n-tricosane), and C25 (n-pentacosane) are indicated. c Profile of an extract of a single, excised scent gland, showing 1,4-benzoquinone (peak A), unknown I (peak C), and 1,4-naphthoquinone (peak E) only