title: Characteristic odor of Osmoderma eremita identified as a male-released pheromone.
abstract: Osmoderma eremita (Scopoli) is an endangered scarab beetle living in hollow trees. It has mainly been known for its characteristic odor, typically described as a fruity, peachlike or plumlike aroma. The odor emanating from a single beetle can sometimes be perceived from a distance of several meters. In this paper, we show that the characteristic odor from O. eremita is caused by the compound (R)-(+)-gamma-decalactone, released in large quantities mainly or exclusively by male beetles. Antennae from male and female beetles responded in a similar way to (R)-(+)-gamma-decalactone in electroantennographic recordings. Field trapping experiments showed that (R)-(+)-gamma-decalactone is a pheromone attracting female beetles. Lactones similar to (R)-(+)-gamma-decalactone are frequently used as female-released sex pheromones by phytophagous scarabs. This is, however, the first evidence of a lactone used as a male-produced pheromone in scarab beetles. We propose that the strong signal from males is a sexually selected trait used to compete for females and matings. The signal could work within trees but also act as a guide to tree hollows, which are an essential resource for O. eremita. Males may, thus, attract females dispersing from their natal tree by advertising a suitable habitat. This signal could also be exploited by other males searching for tree hollows or for females, which would explain the catch of several males in our traps.
authors.affiliation: Department of Ecology, Lund University, SE-223 62 Lund, Sweden. mattias.larsson@vv.slu.se
authors.forename: Mattias C
authors.initials: MC
authors.lastname: Larsson
authors.forename: Jonas
authors.initials: J
authors.lastname: Hedin
authors.forename: Glenn P
authors.initials: GP
authors.lastname: Svensson
authors.forename: Till
authors.initials: T
authors.lastname: Tolasch
authors.forename: Wittko
authors.initials: W
authors.lastname: Francke
mesh_terms: D000818:Animals; D002628:Chemoreceptor Cells / Q000187:drug effects; D001517:Coleoptera / Q000502:physiology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D007783:Lactones / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology; D008297:Male; D009812:Odorants; D012724:Sex Attractants / Q000008:administration & dosage / Q000737:chemistry / Q000494:pharmacology / Q000502:physiology*; D012726:Sexual Behavior, Animal / Q000502:physiology*
chemical_list: D007783:Lactones; D012724:Sex Attractants; C109757:decan-4-olide