Origin: It is believed this animal is native to Europe, but it now is found throughout the world.
Biology: Pillbugs and sowbugs are most closely related to other Crustaceans, such as crabs and crayfish, and similar to their relatives they require areas of high moisture for survival. Breathing is done through primitive forms of gills, and they are unable to effectively control the loss of moisture through these openings, thus restricting them to very damp environments. Food is usually decaying organic and vegetable materials, although they also may attack living plant tissues and turf, as well as fruits and vegetables. Sowbugs and pillbugs can live up to 2 years, and they continue to molt throughout their lifetime. Females produce a batch of around 25 eggs that hatch within a pouch on her ventral side, referred to as a marsupium. The nymphs may be carried in this pouch for an average of about 45 days, at which time they are able to open the pouch and leave of their own accord. After molting again the female regains the use of the pouch and she may have several broods each year.
Identification: Pillbugs are up to a half inch long, dark gray in color, and composed of around 10 lateral plates that overlap each other. They are capable of curling up into a tight, round ball when disturbed. They may be distinguished from sowbugs by this ability to roll into a ball, as well as by the presence of a pair of cerci at the posterior end that are not visible from above. There are 7 pairs of legs.