As the name suggests, the common blue damselfly (Enallagma cyathigerum) is one of the commonest species in Great Britain. They can be confused with other blue damselflies and this situation isn't helped by the fact that the markings on this species are rather variable. Adult males are predominantly blue, spotted with black markings resembling stripes. Adult females are much darker with larger areas of black and usually a green background colour, although there is a blue form, again with larger areas of black.
Dragonflies and damselflies can appear alarming to some people, and their old English country names of ‘horse-stingers’ and ‘devil’s darning needles’ suggests they were once feared. This fear probably stems from the long and usually striped abdomen characteristic of these insects and the fact that they can curl their ‘tails’ down as if preparing to sting. In fact, neither dragonflies nor damselflies have the capacity to sting, although they are predatory insects, both in the larval and adult stages.
All flying insects evolved originally with two pairs of wings although, in some species, the front pair has become modified to act as wing covers. These species include various beetles, crickets and cockroaches. Other insects have effectively lost the hind pair of wings, having two pin-shaped balancing organs in their place. Dragonflies and damselflies have retained both pairs as membranous wings, both effective in flight. Both dragonflies and damselflies are strong and swift fliers, and both pairs of wings are similar in size. Apart from their smaller size and generally more slender build, the easiest way to distinguish damselflies from dragonflies is the position of the wings when the insect is resting. Dragonflies rest with both pairs of wings held perpendicular to the body, whereas damselflies hold them almost parallel.
- Agrion Porte-Coupe, L’agrion Porte-coupe.
- Wingspan: 38mm
- Average body length: 32mm