The beautiful demoiselle (Calopteryx virgo) and its not dissimilar cousin, the banded agrion, rate as two of my favourite insects. Stunningly beautiful in the sun with their metallic finish making them look almost unreal, the colours just being impossible to recreate. Even the male is worthy of the name 'the beautiful maiden'!
The banded agrion is quite common but the beautiful demoiselle is far less so as it has particular preferences in habitat. The beautiful demoiselle likes fast flowing clear, unpolluted water with abundant aquatic vegetation. The upper reaches of some of Dorset's chalk streams are ideal for them. This preference for a special habitat means they are far from common anywhere in Dorset but where they do occur they can be abundant. They are also inclined close to where they laid their eggs so are, by nature, a local species.
It is the absence of the dark patches on the wings of the males that immediately distinguishes them from the banded agrion.