Structure development and evolution of the male pheromone system in some noctuidae (Lepidoptera)

Pheromone systems from seven species of noctuid are examined. Much of the structure of scales from the wings and/or the abdomen is interpreted as a modification for secretion or release of a pheromone. Scales with an extremely complex surface provide a large evaporation surface, while those connected to secretory cells show less superficial folding than body-covering scales. The development of the secretory gland and diseminatory scales in Mamestra configurata is followed from the exuvial pharate adult stage to emergence. Both components are paired and develop from epidermal cells lining a pair of large lateral invaginations. They may have resulted through division of a group of less specialized cells that originally combined the function of pheromone production and release.