Corn moth
(Nemapogon granellus)
Biology:
With a wing span of 14 mm, the corn moth (fam. Tineidae, tineid moths) is one of the smallest moths which damages stored products. The black-brown front wings feature a white and yellow pattern and have grey-brown fringes. The caterpillars are whitish-yellow and reach a size of around 10 mm. The corn moth originally inhabited agarics. As this species is native here in Germany, it can also endure low temperatures relatively well. The Nemapogon granellus moths can be found outdoors primarily in July and August.
Damage:
In addition to in grains, where the moths prefer to eat the seedling, you can find the corn moth in seeds, legumes, dried fruits, almonds, dried mushrooms and sometimes in rotten wood. The caterpillar is sensitive to light and pupates in eroded grains. The webs and faeces cause the affected foodstuff to clump and to develop an unpleasant odour.