Abstract Glands of the 4th and 5th abdominal sternite of the caddis flies Potamophylax latipennis, Potamophylax cingulatus, and Glyphotaelius pellucidus contain (S)-4-methyl-3- heptanone (4a),(4S, 6S)-4, 6-dimethyl-3-octanone (4b), and (4S, 6S)-4, 6-dimethyl-3- ...