The Azure damselfly (Coenagrion puella) is quite common here in The Netherlands, and always a pleasure to see!
At first glance it could be a bit tricky to distinguish the Azure from a Common blue (Enallagma cyathigerum) damselfly, but if you look at the antehumeral stripe (that’s the long blue section on the thorax), the Azure’s blue stripe is narrower than the black stripe beneath it, and there’s an extra black line, a “spur” extending from the wing base towards the legs. The Common blue’s antehumreral stripe is broader than the black stripe beneath it and there’s no “spur” on the thorax.
Another thing to look at is the second segment of the males’ abdomen (just behind the thorax): both are blue but the Azure has a black U-shape and the common blue has a black mushroom-shaped mark.
And now I need your help! Please take a look at the second photo below, it’s not a great shot but I hope someone can help me identify this little damselfly.. I’m doubting if it’s either a Variable damselfly (Coenagrion pulchellum) or perhaps a female Azure in blue form. If you know which one it is, please leave a comment below!