The Small Spreadwing is possibly the most elegant of these. With its very long slender metalic abdomen, blue eyes balanced by a matching-accessory blue band around the "Tail" and a lovely coppery thorax that glints like new coins in the sunlight, it is a truly stunning insect.
It is otherwise known as the Small Emerald Damselfly which can be misleading as mature males such as this one become more coppery coloured than green. The pterostigma here has pale edges characteristic of a Migrant Spreadwing but it is also known to be true in L. Virens in parts of Iberia, as in this case.
It is the only odonate that oviposits (lays eggs) in live wood, and is often found in trees and bushes overhanging water. The action of ovipositing leaves tracks, or scars in the wood, which is usually thin branches with soft bark.
It is an impressive looking insect.
Speaking of yellow and black, here below is a nice shot of what I believe must be a classic "type B" mature female Iberian Bluetail. The bright yellow/green colour, particularly on the thorax with the wide antehumeral stripe, is diagnostic. There are several variations of Bluetails which can be very confusing.
Blue-eye/Goblet Marked Damsel
Common Blue Damsel
Small Red-eyed Damsel
Southern Damsel/Mercury Bluet
Western Willow Spreadwing