This is a large family of micro-moths with 4,000 species worldwide, of which 85 species are found in Britain split into eight subfamilies. Known as the concealer moths, they belong to a superfamily called Gelechioidea. The caterpillars usually feed concealed and protected in silken webs, or rolled within leaves. They also construct tubes or cases from all manner of materials, like soil, dead leaves, and twigs. As well as feeding on a variety of deciduous trees and herbaceous plants, many of these moths feed on dead plant material, rotting wood, dead animals and insects, and play an important part in the recycling and use of nutrients. But they may also become pests when the larva infest stored food stuffs, such as grain. Others may feed on textiles and carpets, and may become a problem in human dwellings.
Both the species above are often found indoors after dark, and are very much attracted to light. I often find them on my bathroom, kitchen or dining-room walls. They are quite small with only a forewing length of up to 12mm (half an inch). Both species originated from Asia, and have become common and widespread throughout Britain. They can be seen all year round, but mainly in the summer.
The larvae feed on dead plant and animal matter, guano, wool, and old textiles like wool and leather. They can be a particular problem in museums as well as households. The larvae spins a silken hideout from which it feeds.
May and June 2011, rear garden, Staffordshire. © Pete Hillman 2011.