Surprisingly, New Zealand has a relatively small number of Noctuidae, with about 140 known species being endemic to the country and occurring nowhere else . In New Zealand, the sex pheromone has been identified for only one other noctuid species, Graphania mutans (Walker) . Two distinct taxa within G. mutans were found. Females from an Auckland population produced (Z)-9-tetradecenol (Z9-14∶OH), (Z)-9-tetradecenyl acetate (Z9-14∶OAc), (Z)-7-tetradecenol (Z7-14∶OH) and (Z)-7tetradecenyl acetate (Z7-14∶OAc), while females from a Canterbury population produced these four compounds plus (Z)-9-tetradecenal (Z9-14∶Ald). Male responses from each population were specific to the pheromone blend produced by females of the same population. This work was undertaken to identify the sex pheromone of T. atristriga and to develop a lure for monitoring and possible control of this pest. In addition, the identification of the sex pheromone of a second noctuid species will help to understand the biology, ecology and behaviour of this pest as well as shed light on the evolution and speciation of Noctuidae species in New Zealand. Here, we report the conclusive identification of the pheromone blends of T. atristriga and the evaluation of their biological activity in field bioassays in Canterbury, New Zealand.