Neryl decanoate: female sex pheromone of the click beetle Dalopius marginatus

Dalopius marginatus (L.) (Coleoptera: Elateridae) is a very common click beetle species developing in forest soils in an area from southwest Europe to eastern Siberia. Here, we studied the composition of the female-released sex pheromone of D. marginatus using coupled gas chromatography-mass spectrometry (GC-MS). Neryl octanoate, neryl decanoate, and neryl dodecanoate, in a ratio of approximately 1:100:3, were the only volatile compounds present in the extracts of the pheromone glands. The main compound neryl decanoate proved to be highly attractive to swarming D. marginatus males in the field, whereas adding the two trace compounds in the natural ratio did not influence its attractiveness. Although closely related to the genus Agriotes, D. marginatus is distinct in the use of neryl compounds with comparatively long acid moieties, as opposed to the use of geranyl- and/or (E,E)-farnesyl esters of shorter-chain fatty acids as sex pheromones in Agriotes species.