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Several emerald damselflys were discovered flying among the thick vegetation surrounding the sphagnum pool at The Backwarden EWT Reserve, Danbury on July 11th. They seemed too robust for Common Emeralds, Lestes sponsa, and thanks to the wonders of digital photography (and its zoom facility) it proved possible to observe the critical distinguishing characteristics between this species and the Scarce Emerald Lestes dryas from even small photographs. To elaborate, the tips of the males inferior anal appendages are bent towards each other at the tip and the prunosity on segment two of the abdomen is restricted to the top two thirds. Both these features can be seen (I hope) on the photographs. The Sphagnum Pool meets this species ecological requirements exactly, especially following recent conservation work to remove some of the reedmace surrounding it.  It regularly floods in winter and dries out in summer, the mud (resulting from the reedmace removal) being colonised by a thick cover of emerging vegetation such as Juncus rushes, spike-rush and Lesser Spearwort. Later in July several pairs were observed mating and, on August 2nd, females egg laying. In total, around fifteen individuals were seen. This species has always been associated with coastal borrowdykes in Essex, especially those containing beds of Sea Club Rush. The map in Ted Benton's and John Dobson's 'Dragonflies of Essex' (2007) show only two inland locations (in TQ59 and TQ69), the rest being confined to tidal river systems. The current British Dragonfly Society website maintains the impression that this species is strictly coastal but the population dynamics of dragonflies in this country is changing year or year and I have heard rumours of a number of other inland sites in Essex. Still, it is encouraging that this species has colonised The Backwarden following conservation work, even if that work was intended to benefit the Great Crested Newts!