Appearance:

The moth has a wing expanse of 20-22 mm. When at rest with the wings forming a roof over the body, it is 10-14 mm long. On the blue-grey background of the forewings are transverse, dark, wavy bars, with a row of dark spots at the tips. The caterpillars are white, sometimes pinkish or greenish; head and neck shield are brown. They grow to 15-20 mm. The brown, spindle-shaped pupa in the cocoon is about 9 mm long.

Life History:

During the day, the moth usually clings to ceilings and walls, and flies about at dusk. The female lays an average of about 200 eggs. The caterpillars are very active spinners. Pupation occurs in a cocoon covered with nutrient particles. The total development period in Central Europe is about 3 months. In warmer climates it may be completed in 4-6 weeks.

Distribution:

In most countries with temperate climate.

Damage:

The caterpillars live on flour, bran, whole meal, flakes, grain, nuts, etc. They are serious pest in mills where their webbing may clog machinery.