Sword-grass Xylena exsoleta
Wingspan 58-68 mm.
Commoner in the north of England and Scotland than elsewhere, where it was formerly widely distributed. Most recent southern records may be due to immigration.
The adults fly in moorland and woodland habitats from September onwards. They then hibernate for the winter and reappear in March or April.
The rather bright green caterpillar is marked with black blotches and whitish lateral lines. It feeds on a number of plants including dock (Rumex) .