There is no specific life expectancy for adult insects since the life spans vary between the species, but it can usually be measured in days. Some adult insects, such as the mayfly, live less than 24 hours, while other species, especially social insect queens, live for decades.
Insects are one of the rare animals that can spend long periods in their developmental stages. Cicadae spend between 13 and 17 years in the ground developing as larvae, but when they emerge as adults, they live less than one month. Some species of long-horned beetles can live up to 35 years as larvae.