Communal silk web constructed by the gregarious larvae (caterpillars) of the Spindle Ermine Moth, Yponomeuta cagnagella. Ermine moths are micro-moths; the genus Yponomeuta is comprised of 8 species. All are characterised by gregarious larvae that produce extensive webs, and whose feeding often results in the complete defoliation of the host plant, including large trees, or tens of metres of hedgerows. The web is thought to act as a protective layer against predation by birds. In this picture the green leaves visible are common ivy, Hedera helix, growing through an isolated bush of Common Spindle, Euonymus europaeus in a roadside hedge. All of the leaves of the bush have been eaten. The picture was taken in Norfolk UK in May.