the invention disclosed relates to the detection of the emerald ash borer , agrilus planipennis fairmaire and in particular to the use of contact sex phenomones therefor . analysis of the elytral hydrocarbons from male and female emerald ash borer , that were freshly emerged vs . sexually mature revealed a female - specific compound , 9 - methyl - pentacosane , only present in sexually mature females . this material was synthesized by the wittig reaction of 2 - decanone with - triphenylphosphonium bromide followed by catalytic reduction to yield racemic 9 - me c 25 , which matched the natural compound by gc / ms . in field bioassays with freeze - killed sexually mature a . planipennis females , feral males spent significantly more time in contact and attempting copulation with unwashed females than with females that had been washed in n - hexane to remove the cuticular hydrocarbons . hexane - washed females to which 9 - me - c 25 had been reapplied elicited similar contact time and percentage of time attempting copulation as unwashed females , indicating that 9 - methyl - pentacosane is a contact sex - pheromone component of a . planipennis . this is the first contact sex pheromone identified in the buprestidae .