The double square-spot (Xestia triangulum) is a moth of the family Noctuidae. It is distributed through most of Europe except Portugal, the Mediterranean islands and northernmost Fennoscandia. In the East, the species ranges East across the Palearctic to Siberia and in the South-East to the Black Sea and in Iran. It rises to a height of about 2000 metres in the Alps. Differences: Technical description and variation: The wingspan is 36–46 mm.Forewing grey brown, with a rufous tinge: a small blotch at base, a praeapical costal spot, and the cell prominently black brown; hindwing fuscous.