Woodlice

Woodlice are crustaceans related to slaters, shrimps, lobsters and crabs. They are the only crustaceans that have properly invaded land, without the need to return to water in order to breed, although they tend to be restricted to fairly damp places. Woodlice are quite harmless and in fact beneficial in their proper habitat by promoting the breakdown of dead vegetation and organic matter in the soil. They normally live outdoors but shun the light by hiding under stones, logs, loose bark, leaf-litter etc., or in hollow tree-trunks - almost anywhere that is fairly damp. However, they frequently come indoors and may take up residence inside buildings, surviving in any dark, damp places they can find. When large numbers of woodlice are found indoors, perhaps clustered in wall crevices or under skirting boards etc., it is always worth checking for excessive dampness in these places - just in case there is a structural problem with the damp proofing or damp course. Woodlice are easily controlled with insecticides or silica dust.

Woodlice: Description & Life Cycle

There are about 35 species of woodlouse in Britain but the one you are most likely to find indoors is the common Garden Woodlouse.

Description:

adults are about 15mm ( 1/2 inch) long
grey speckled back
13 horny articulated segments
small head
elbowed antennae
seven pairs of short legs
and a very short tail
breathe through air holes in the hindmost pair of legs

Life cycle:

female produces up to 150 eggs
they are contained within a pouch in her body until they hatch
when hatched they are released into the environment
the young woodlouse is about 2mm long and white in colour
only one generation per year