Chemistry of defensive secretions of bombardier beetles (Brachinini, Metriini, Ozaenini, Paussini)

Data are given on the chemical composition of the defensive secretions of species of carabids of the genera Brachinus, Stenaptinus, Metrius, Goniotropis, Pachyteles, Ozaena, and Homopterus. All produce quinonoid secretions, containing from one to three of four different benzoquinones (1,4-benzoquinone; 2-methyl-1,4-benzoquinone; 2,3-dimethyl-1,4-benzoquinone; 2-methyl-3-methoxy-1,4-benzoquinone). In most species the secretions also contain n-alkanes (tridecane, tetradecane, pentadecane).