Dragonflies are insects in the sub-order Anisoptera (meaning "unequal-winged"). Hind wings are usually shorter and broader than forewings. They are usually large, strongly flying insects that can often be found flying well away from water. When at rest, they hold their wings out from the body, often at right angles to it. The eyes are very large and usually touch, at least at a point. The larvae have no external lamellae (gill plates).
The labelled diagram below may help to define the various anatomical terms used in the descriptions in the species pages.
In Great Britain and Ireland there are about 30 species that may be encountered and one that has become extinct. These species fall into 5 families and 14 genera. A partial taxonomic "tree" for the dragonflies is shown below.
Click on images to enlarge.