Several moth caterpillars are "case-bearers", constructing a sand/grit-rendered "case" (above), often silk-lined, in which the caterpillar lives and pupates. The case can also be of wood/vegetable matter or of soft material like card or hair.

A couple of days before this caterpillar was seen climbing the wall, the flat roof had been re-surfaced with mineral felt, leaving a lot of loose grit around. This fashion-conscious caterpillar even built a light-coloured band into the grit case!

The larva above has dark head, body and legs and is one of the several other UK case-bearing caterpillars.

One of the more common is the Case-bearing Clothes Moth, Tinea pellionella, a mid brown moth with a few dark dots and gingery head hair. Related to the Common Clothes Moth, it may live in buildings or outside. Its main claim to fame its the silk-lined case, which can be of hard grit or soft material like card or hair.

Larva of Case-bearer moth Tinea pellionella and its case-bearing, close relative Tinea dubiella both have a dark brown head and one other dark segment on a WHITE body with white legs.

The adult moth has a wingspan of 9-16mm and occurs throughout most of the world.

Another case-bearing moth caterpillar is the Household Case-bearer (above), which looks similar but has a dark head plus three dark segments instead of two. It can emerge from either end of the flattened case. The adult moth is also similar in looks and habits to the Case-bearing Clothes Moth, eating dead organic material including insects, dust (dead skin) and spiders' web. An Afro-tropical moth, it has been introduced to the Canary Islands (as above), Madeira, South Asia, and other areas. Its close relative The Plaster Bagworm, P. uterella, is also similar.