The wingspan is 35–40 mm. Forewing grey speckled with darker, and more or less tinged with brown; the veins dark; inner and outer lines double, dark filled in with pale ground colour, conversely lunulate-dentate; the inner line sometimes forming a sharp outward angle below vein 1, meeting the median line, sometimes rounded ami remote from it: claviform brown, darker edged, variable in size, often quite small; orbicular and reniform pale with dark centres, the latter with white dotted annulus and often followed by a pale patch; marginal area dark grey beyond the pale submarginal line, which is preceded by brownish patches at costa and on both folds: hindwing dirty whitish, with darker cellspot, veins, and outer line, the terminal area diffusely fuscous, with the submarginal line showing paler along termen; in typical sordida the brown tints are confined to the two folds: -in anceps Hbn. these brown tints pervade more or less the whole forewing: - ochracea Tutt has the ground colour paler and the suffusion more rufous brown; renardii Bsd. is a very pale form with the markings subobsolete; while engelhartii Duurloo represents a renardii pale form from eastern Jutland with indistinct markings; - ab. mediana ab. nov. [Warren] appears very distinct; the brown-grey ground colour is without dark speckling; the inner and outer lines are single, black and distinct, the outer with clear black teeth on the veins; the median shade, generally inconspicuous, is thick and black, distinctly angled outwards on subcostal and veins 1 and 2; the space between it and outer line deeper brown: the markings of the hindwing clearer; the male specimen from Germany without precise locality.[1]
Adults are on wing from June to July.
Larvae, caterpillars
The larvae feed on the flowers and leaves of various grasses, including Poa annua and Dactylis glomerata.[2] The caterpillars overwinter. They feed on grasses and are also considered pests of cereals.[3]
References
^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
