Emperor dragonfly  (Anax imperator)

The emperor is Britain's largest dragonfly; they are a spectacular sight with their broad wings and powerful flight. After emerging, both sexes are pale green with brownish markings. The legs are brown, becoming yellowish towards the base; the wings have black veins, and take on a yellowish-brown tinge with age. Males develop a bright blue abdomen with a black 'fish-bone' line passing down the centre; the thorax and head are green and the prominent eyes are blue. Females have similar markings to males, but are mainly green in colour, becoming brownish on the last few segments of the abdomen. Both sexes possess appendages at the tip of the abdomen known as 'claspers', which are used in mating; in males these claspers are more robust than in females (2). The larvae or 'nymphs' are brownish in colour and have stocky bodies with rounded heads that feature very large eyes (3).