In the male, sperm produced in segment 9 of the abdomen is transferred to a secondary set of genitalia located at the opposite end of the abdomen, in segments 2 and 3. This requires that reproduction is not performed with abdomens ‘tip to tip’, as with other insects.
During copulation, the male uses special claspers situated at the very tip of the abdomen to hold the female in the tandem position. In dragonflies, the female is held by the head, while in damselflies she is held by the pronotum, a shield-like structure located just behind the head.
The female then manoeuvres into the wheel position so that sperm transfer can take place. Dragonflies and damselflies can often be seen in tandem and wheel positions, either stationary at rest on vegetation or flying. Some species can remain coupled this way for many hours, but for some species copulation lasts only seconds and is done on the wing.
Typically, damselflies usually remain in tandem, or with the male close by, while the female lays her eggs (ovipositing). This is less common with dragonfly species, and in some species, such as hawkers, the female lays eggs completely alone.
Fertilised eggs are laid immediately, there is no gestation period. Damselflies will sometimes completely submerge underwater to lay their eggs, and the male will assist in breaking free of the water’s surface tension to take to the air again. Species like Darters and Chasers merely dip their abdomen into the water to deposit their eggs, where they fall to the bottom. Other species inject their eggs into mud, rotting wood or vegetation, or emergent bankside plant and reed stems.
Usually, eggs hatch after a few weeks, but in some species, they will hatch the following spring.