The Common Emerald (Hemithea aestivaria) is a moth of the family Geometridae. The species is found througout the Nearctic and Palearctic regions and the Near East. In the British Isles it is not found in Scotland but is a common species elsewhere.

All wings are generally dark green with grey and white chequered fringes and narrow white fascia, two on the forewing, one on the hindwing. The green colouration tends not to fade over time as much as in other emeralds. The hindwings have a sharply angled termen giving the moth a very distinctive shape. The wingspan is 30-35 mm. It flies at dusk and night in June and July and will come to light.

The larva is green with reddish-brown markings and black v-shaped marks along the back. The young larva will feed on most plants but later it feeds on trees and shrubs including birch, blackthorn, hawthorn, oak and sallow. The species overwinters as a larva.

References

• Chinery, Michael Collins Guide to the Insects of Britain and Western Europe 1986 (Reprinted 1991)
• Skinner, Bernard Colour Identification Guide to Moths of the British Isles 1984