Mercuurwaterjuffer
(Coenagrion mercuriale)

The Mercury Bluet is one of a trio of very similar-looking Mediterranean species of the genus Coenagrion, the other two being C. caerulescens and C. scitulum. Coenagrion mercuriale is a small, black-and-blue damselfly. It's fairly widely distributed throughout Iberia, France, Italy and Germany but is seldom found in large populations. The species' main distinguishing features include its dark-centred pterostigma, its preference for running rather than stagnant waters, and the female's blue-ringed segment boundaries between S8, S9 and S10. For a comparison of the male appendages in these three species, hover your mouse pointer here. [Please note that all the photographs below are of the Italian subspecies C. m. castellani.]

For an overview of the Mercury Bluet's distribution in Europe, hover your mouse pointer over the map symbol .
With the authors' permission we have based this map on data published in Kalkman et al. (2010).

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