LThere are three stages in the life-cycle of all dragonflies. The egg hatches into the larva (also known as a nymph), which moults up to 15 times before emerging as an adult. Unlike most other insects, there is no pupal stage and the transition from larva to adult is known as incomplete metamorphosis. This is not necessarily an annual cycle, since the larva may spend more than a year underwater before emerging as an adult. The adult stage is usually the shortest in the life-cycle and rarely lasts for more than a week or two in Britain.