Carpet beetle hair. Coloured scanning electron micrograph (SEM) of the spear-headed hair (hastisetae) of a carpet beetle larva (family Dermestidae). These hairs, which are found at the back of the beetle, can cause lung and skin irritation, and gastric problems. Carpet beetle larvae are found in the dirtier areas of homes. Because of their hairy appearance they are often known as woolly bears. They are a significant pest, feeding on animal materials including fur, feathers, hair, leather and other fabrics, and stored food products.