The wingspan is 32–38 mm. Its forewings are grey white; a bifurcate black streak from base below cell; lines indistinct, pale with dotted edges; stigmata grey with partial black outlines and paler rings; the lower lobe of the reniform orange tinged; claviform sometimes connected by a black streak with outer line, and often a dark spot between the stigmata; submarginal line waved, white, preceded by dark marks; hindwing grey; the whiter forms are separated as ab. pallida Spul.[1]
LarvaHabitat in the Czech Republic
Biology
Adults are on wing from late August to November and, after overwintering, again from the end of February to mid-May. The larvae are bluish green dotted with white; dorsal and subdorsal lines white; spiracular line yellowish white. The larvae feed on various deciduous trees, but mainly oak (Quercus species) and can be found from April to June. It overwinters as an adult.[2] It is mainly found at the edges of forest and meadow habitats as well as in heathlands and park landscapes.
^Seitz, A. Ed., 1914 Die Großschmetterlinge der Erde, Verlag Alfred Kernen, Stuttgart Band 3: Abt. 1, Die Großschmetterlinge des palaearktischen Faunengebietes, Die palaearktischen eulenartigen Nachtfalter, 1914
