As its the British Dragonfly Society’s National Dragonfly week I thought I’d celebrate by posting about a species a day of these marvellous insects. First Up the Magnificent Emperor Dragonfly Anax imperator
Its our largest dragonfly growing to 78mm in length and with a wingspan of 106mm, though some argued the female golden ringed is larger with a maximum length of 84mm, but a wingspan of 101mm (Smallshire and Swash, 2004), it is more slender than the emperor. The males are an impressive sight to behold as the patrol an area of lake margin or a pond, fighting with other males and other dragonfly species and chasing prey, small items which they often eat on the wing. They have even been known to eat other dragonflies!
The larva or nymph live in the vegetation in the ponds hunting other pond creatures including tadpoles and mayfly larva. I have noticed that the smaller instars (stages of the larva form) seem to often be striped in this species.
They grow over 1 or 2 years and at full size they are the biggest dragonfly nymphs (only the rare vagrant/occasional breeder, the lesser emperor matches its size), which can grow to 56mm long (Cham, 2006), big enough to take small fish! Once fully grown they emerge, from mid May onwards, crawling out of the pond to become an adult dragonfly.
So that is species one, I could say so much more, but it will have to wait for another time.
Tomorrow: the Scarce emerald damselfly
More on Dragonflies here: British dragonfly society
D. Smallshire and A. Swash, 2004, Britain’s Dragonflies, Wild Guides Ltd.
S. Cham, 2006, Field Guide to the larvae and exuviae of British Dragonflies Dragonflies Volume 1: Dragonflies (Anisoptera), The British Dragonfly Society