Woodlice are crustaceans that live in damp, dark places. They can be found wherever there is wood to eat and moist soil or leaf litter rich in organic matter. There are more than two thousand species of woodlice worldwide. Some feed on fungi, others graze on algae or lichens, but most prefer dead plant material such as rotting leaves, bark, or mosses. Woodlice range in size from 0.4-1 inch (10-25 millimeters) long and have a flattened body with seven pairs of legs for walking around on the surface they inhabit.