The adults actually do no damage when feeding. It is the larvae, which hatch from the sticky eggs, that eat wool, hair, fur or feathers. However, they prefer blankets, wool carpets, wool garments or upholstery that has been soiled with perspiration. The grubs are white caterpillars with golden brown heads, which spin a hiding place of characteristic loose silk webbing, beneath which they feed. They make irregular holes in textile fabrics and pupate as silken cocoons.
In the UK, there are four main species of Clothes Moths that can be found in homes, all of them characterised by folding their wings tent-wise along their backs:
- The Common Clothes Moth is 6 to 7mm long with pale, plain golden buff wings fringed with hair. The grubs cause irregular shapes in textile fabrics
- The Case Bearing Clothes Moth are rarer and more dull in colour. They have three dark brown spots on each of its wings. The grubs produce an open ended cylindrical case of silk as it feeds and attaches fibres of its food material to this in order to camouflage itself
- The Brown House Moth have golden-bronze wings, flecked with black that fold along its back. The adult is about 8mm and prefer to run rather than fly. The eggs are attached to fabric when laid, on which the grubs feed. They are creamy -white caterpillars with brown heads
- The White Shouldered House Moth have mottled wings with a white head and ‘shoulders’ where the wings join the body. They can grow up to 18mm long. The grub is a general scavenger as well as a textile pest