It is distributed throughout Europe, although it is not present in southern Spain and Greece, as well as northern Fennoscandia.

There is usually a bold cross-shaped black mark in the centre of the wing which has been likened to the Greek letter chi (Χ) and gives the species its common name.

Forewing chalk white, grey-speckled; the lines double, grey; median area darker, the stigmata pale grey and conspicuous; the claviform at extremity edged with black and joined by a black dash to the inner blacker arm of outer line; submarginal line formed of whitish spots preceded by black wedge shaped marks; hindwing of male white with interrupted grey submarginal band; of female blackish grey, with darker cellspot, veins, and outer line; the females are always darker grey than the males; — olivacea Stph.

langei Harrison (34 a) is like olivacea but the submarginal line is absent, and the black marks preceding it wholly or nearly obsolete.

[1] This moth flies at night in August and September[1] and is attracted to light and sugar.