Small Emerald Hemistola chrysoprasaria
(Esper, 1795)Wingspan 28-32 mm.
Occurring in the southern parts of Britain, and becoming scarcer north of the Midlands, the Small Emerald inhabits woodland edges and hedgerows mainly on chalk downs and limestone where the foodplant grows.
The adults are on the wing in July and August.
The larva feeds on Traveller's joy (Clematis vitalba) in September and October when it is brown, matching dead Clematis stems and reaching about 12 mm length. From November to March it diapauses before completing feeding and growth in April and May when it is green, matching live Clematis.
The larva is easily distinguished from other Clematis feeders by the pair of forward pointing cones on thoracic segment one (T1), the head divided into two cones, and its many small white warts.
Records from areas lacking wild Clematis vitalba are sometimes due to confusion of its vernacular name with that of Little emerald (Jodis lactearia).