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Length: Male: 37mm; Female: 34mm
The Scarce Emerald Damselfly is a medium sized metallic green insect that usually rests with its wings half open. Adult males have blue eyes and have powder blue pruinescence on the thorax between the wings and on the segments at the top and bottom of the abdomen. In comparison, the females tend to be much duller green.
Management Fact File
L. dryas is usually found within the dense vegetation of shallow pools and drainage channels. On the coastal and estuarine marshes in Kent and Essex populations also use the borrow dykes as well as ditches and marsh pools where they show a tolerance of brackish water. Breeding sites are well vegetated with submerged and emergent vegetation.
Status & Distribution
It is a rare and local species, recognised as vulnerable by the UK statutory conservation agencies. It is listed under Category 2 (vulnerable) in the British Red Data Book on Insects.
In Britain the species has strongholds on the coastal and estuarine marshes of Essex and North Kent and in the Norfolk Brecklands. There are also a few scattered colonies at other locations in East Anglia.
Other Lestes species are similar. It can be distinguished from the commoner L. sponsa by the less extensive pruinescence on the mature male and the curved rather than straight anal appendages. The female has square dark spots on segment 1 rather than rounded as in sponsa (difficult to see in the field). The ovipositor extends just beyond the end of S10.