The Azure damselfly occurs in much of the UK and Europe except the far north of each. The blue male, shown above coupled with the female, is less blue than the similar Common Blue Damselfly. On the second segment of the abdomen, he has a distinctive black, rectangular, horseshoe shape, followed by, but separate from, a thin black ring.
Yellow form of the female
Coupled in mating wheel
Male and green female in tandem, he leading and protecting her as she deposits her eggs ("ovipositing") on the underside of aquatic plant leaves.
Azures sometimes have a mass, communal oviposit
The male Common Blue has one black stripe on the side of the thorax; the Azure has a wider one and an additional, thinner one.