How many stages do insects undergoing complete metamorphosis experience?

Insects that undergo complete metamorphosis experience four distinct life stages: egg, larva, pupa, and adult. This process begins when an insect lays eggs, which hatch into larvae, commonly referred to as caterpillars in the case of butterflies or maggots for flies. The larval stage is focused on growth and feeding. After a period of development, the larva enters the pupal stage, during which it undergoes significant transformation within a protective casing, such as a chrysalis or cocoon. Finally, the adult stage emerges, showcasing a fully developed form capable of reproduction.

This four-stage process is a key characteristic of complete metamorphosis, distinguishing it from incomplete metamorphosis, which involves only three stages: egg, nymph, and adult. Understanding this cycle is essential for category 1 applicators when considering pest management and biological control strategies, as different life stages may require different approaches to effectively manage pest populations.