Armadillidium m is a genus of the small terrestrial crustacean known as the woodlouse. Armadillidium are also commonly known as pill woodlice, pill bugs or roly-poly, and are often confused with pill millipedes such as Glomeris marginata. They are characterised by their ability to roll into a ball when disturbed. They typically feed on moss, algae... Found on http://en.wikipedia.org/wiki/Armadillidium