Woodlice are common inhabitants of woodlands and gardens. There are about 35 species of woodlice in Britain.
Habits
Some woodlice come indoors, especially during the cooler autumn and winter weather, and of those, the one most likely to be seen is the common or garden woodlouse (Porceklio scaber). Woodlice in houses are entirely casual visitors, searching usually for some protection from the start of cold weather, and encouraged by the build up of vegetation in pot plants or other suitable places immediately outside the house. Woodlice are not insects but small crustaceans, the same class of animals which includes crabs, lobsters, prawns and crayfish. Most of the crustacea live in water but a few, like woodlice, live on land.
Because of the way they breathe using external gills, they need to live in damp places such as under stones, flower pots and in connection with dead and rotting vegetation.