What emerges from the egg is tiny and tadpole-like, and designed to escape from the egg. In cases where the egg is laid above the waterline, this ‘prolarva’ wriggles to safety as soon as it hatches and moults within a few hours. Prolarvae emerging from eggs laid below the waterline moult almost immediately after hatching. During its time as a larva, the dragonfly catches and eats live prey at every opportunity, moulting a further 5–14 times until it is fully-grown.
Larval development typically takes one or two years, but ranges from 2–3 months in the case of the emerald damselflies to more than five years in Golden-ringed Dragonfly. Development takes longer in cooler waters where food is scarcer, whilst in warm waters, such as those of southern Europe, there may be more than one generation per year. With global warming, two generations per year may become increasingly possible for some species in Britain and allow southern species, such as Red-veined Darter, to become firmly established. In any case, it is worth remembering that dragonflies spend most of their lives underwater and only pass a few days or weeks in the adult form.