TY - JOUR T1 - Male sex pheromone components in the butterfly <em>Heliconius melpomene</em> JF - bioRxiv DO - 10.1101/033506 SP - 033506 AU - Sohini Vanjari AU - Florian Mann AU - Richard M. Merrill AU - Stefan Schulz AU - Chris Jiggins Y1 - 2015/01/01 UR - http://biorxiv.org/content/early/2015/12/02/033506.abstract N2 - Sex specific pheromones are known to play an important role in butterfly courtship, and may influence both individual reproductive success and reproductive isolation between species. Extensive ecological, behavioural and genetic studies of Heliconius butterflies have made a substantial contribution to our understanding of speciation. However, although long suspected to play an important role, chemical signals have received relatively little attention in this genus. Here, we combine morphological, chemical and behavioural analyses of a male pheromone in the neotropical butterfly Heliconius melpomene. First we identify specialized brush-like scales that are putative androconia, and lie within the shiny grey region found on the hindwing of males. We then describe six putative male sex pheromone compounds, which are largely confined to the androconial region of the hindwing of mature males, but not immature males or females. Finally, behavioural assays reveal subtle, but detectable, differences in female response to models scented with hindwing androconial extracts of mature conspecific males as compared to unscented controls. Collectively, the results describe structures involved in release of the pheromone and a list of potential male sex pheromone compounds triggering a behavioural response in females. ER -