Wingspan 68–96 mm. Forewings grey-brown with indistinct grey-white pattern of numerous wavy lines. Hind wings grey-brown with few markings. Thorax velvety brown-grey with black transversal stripe.

The eggs are pale brown and oblong and are deposited in clusters in bark crevices, often near old holes of caterpillars or other damage.

Up to 90–100mm and are approximately 1 cm thick. The body is shiny reddish purple on the sides, becoming lighter to pink; the head and neck plate are shiny black and the stigmas are also black.

The caterpillar develops under the bark and deeper in the wood of at least partially living deciduous trees, especially in willows and poplars. It hibernates two to four/five times, sometimes the last hibernation takes place in a cocoon. The caterpillar holes are located low in the trunk and can be recognized by the presence of wood powder and the sour smell (vinigar) that the caterpillars secrete. They usually leave their tree and create a cocoon in the soil in some distance.
The adult moths come to light.

The polyphagous larva feeds on the wood of various deciduous trees like Salix, Betula, Populus, Alnus, Juglans regia, Quercus robur, Fagus sylvatica, Castanea sativa, Pyrus communis, Malus domestica, Prunus, Cydonia oblonga, Fraxinus excelsior, Olea europaea, Ulmus glabra, Tilia, Acer platanoides, Aesculus, Platanus, Morus, Hippophae rhamnoides, Vitis, Lonicera xylosteum, Lonicera etc...Also reported on Larix, but this exceptional.
Host plants are known from more than 20 different plant families.

It prefers a moist environment like river banks, swamps, forest edges, riparian woodland, scrub, gardens, grasslands etc...