Sex pheromone of the American warble fly, Dermatobia hominis: the role of cuticular hydrocarbons.

Chemical communication between adults of the American warble fly, Dermatobia hominis (Diptera: Oestridae), was investigated by electroantennography and behavioral bioassays. Significant electroantennographic responses were recorded from both sexes to hexane-soluble cuticular lipids from either sex. Olfactometer tests indicated an attraction between males and females, and between females. Copulatory behavior of males with a white knotted string treated with female extract confirmed production of a sexual stimulant by females. Such behavior was not observed in tests with male extract, demonstrating that the pheromone acts also as a sex recognition factor. Cuticular hydrocarbons of sexually mature female and male D. hominis were identified by Gas chromatography-mass spectrometry and consist of a mixture of saturated n-, monomethyl-, and dimethylalkanes in both sexes. Sexual dimorphism was characterized by a higher relative concentration of dimethylalkanes in males and the presence of alkenes only in females.