Giant emperor moth. Macrophotograph of a male giant emperor moth, Arctornis l nigrum, a member of the tussock moth family (Liparidae). Its smell organs are on its feathery antennae. The large surface area of these antennae allows the moth to detect tiny amounts of odour. This allows the moth to sense the presence of a female up to several kilometres away. This long-range communication is important for the moths' chances of meeting and mating because the females are relatively inactive and the male moths have a short life.