Double Square-spot Xestia triangulum
(Hufnagel, 1766)Wingspan 36-46 mm.
Frequenting mainly wooded habitats, this species occurs fairly commonly throughout the British Isles.
The single generation flies in June and July and visits light and sugar, as well as certain flowers.
The polyphagous caterpillars hibernate when quite small and feed in spring on various trees and shrubs.