Coenagrion mercuriale

Coenagrion mercuriale, the southern damselfly, is a species of damselfly in the family Coenagrionidae. It is found in Algeria, Austria, Belgium, France, Germany, Italy, Liechtenstein, Luxembourg, Morocco, the Netherlands, Portugal, Romania, Slovakia, Slovenia, Spain, Switzerland, Tunisia, and the United Kingdom. Its natural habitats are rivers and freshwater springs. It is threatened by habitat loss.

The specific part of the scientific name, mercuriale, is because of the distinctive markings on the second segment of the abdomen that resembles the astrological symbol for the planet Mercury - ☿. This also gives the species an alternative common name of mercury bluet.