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Wheel bugs (Heteroptera: Reduviidae: Harpactorinae: Arilus) are general predators, the females of which have reddish-orange subrectal glands (SGs) that are eversible like the osmeteria in some caterpillars. The rancid odor of Arilus and other reduviids actually comes from Brindley's glands, which in the North (A. cristatus) and South (A. carinatus) American wheel bugs studied emit similar blends of 2-methylpropanoic, butanoic, 3-methylbutanoic, and 2-methylbutanoic acids. The Arilus SG secretions studied here are absolutely species specific. The volatile SG components of A. carinatus include (E)-2-octenal, (E)-2-nonenal, (E)-2-decenal, (E,E)-2,4-nonadienal, (E)-2-undecenal, hexanoic acid, 4-oxo-nonanal, (E,E)-2,4-decadienal, (E,Z)-2,4- or (Z,E)-2,4-decadienal, and 4-oxo-(E)-2-nonenal; whereas in A. cristatus the SG secretion contains β-pinene, limonene, terpinolene, terpinen-4-ol, thymol methyl ether, α-terpineol, bornyl acetate, methyl eugenol, β-caryophyllene, caryophyllene oxide, and farnesol. Arilus spp. SG secretions may be sex pheromones, but verification of this hypothesis requires further testing.

Two male-specific beetle volatiles were found that elicited strong gas chromatographic-electroantennographic responses from both sexes of Asian longhorned beetle adults, Anoplophora glabripennis. The secretion consisted of a ~1:1 (v/v) blend of functionalized dialkyl ethers, 4-(n-heptyloxy)butanal and 4-(n-heptyloxy)butan-1-ol. These compounds are chemically unusual natural products that are previously unknown frominsects . Laboratory olfactometer studies showed that a blend of 10 µg of each synthetic compound on a filter paper strip was significantly attractive to ALB adults.

Isomeric compounds reportedly released by mature males of Nezara viridula as attractants for conspecific females are evidently artifacts formed by dimerization of (E)-4-oxo-2-hexenal. Additional analyses of the male-specific volatiles from Italian, Australian, Brazilian, and Japanese populations of N. viridula verify that at least two distinctive pheromone strains exist, but an active synthetic pheromone has not yet been developed. Analyses of volatiles from N. antennata and Acrosternum aseadum males are also reported showing that the native Japanese Nezara sp., and species in the sister genus Acrosternum, produce species-specific blends based on the same compounds as N. viridula: (Z)-a-bisabolene (1-methyl-4-(1,5-dim ethyl-(Z)-1,4- hexadienyl)-cyclohexene), and trans- and cis-1,2-epoxides of (Z)-a-bisabolene. The trans-/cis- 1,2-epoxide ratio of N. antennata is within the range found for most N. viridula populations, but the blend from Japanese N. viridula males deviates radically from those of other conspecific populations.

Male predaceous stink bugs (Pentatom idae: Asopinae) in the genus Podisus release longrange attractant pheromones from a pair of hypertrophied glands opening underneath the wings. Pherom one com positions are reported for four additional Podisus spp.: two Neotropical species (P. connexivus and an undetermined Podisussp.), and two Nearctic species (P. placidus and P. mucronatus). Males of each species release (E)-2-hexenal, plus species-specific major components that include a-terpineol, linalool, 9-hydroxy-2-nonanone, and (E)-2-hexenyl tiglate. The pheromonal chemistry of the Neotropical species closely resembles that for the previously studied Nearctic species, P. macuiiventris and P. fretus.