• "Pill bugs" or "Sow bugs" Armadillidium Valgare
• Phylum, Arthropoda; Class, Malacostraca; Order, Isopoda
• This group includes shrimp and crabs, they are not really "bugs".

Appearance (Morphology)  Color varies from dark gray to white with or without pattern

• Three body parts: head, thorax, abdomen
• One prominent pair of antennae (one inconspicuous pair)
• Simple eyes
• Seven pairs of legs
• Seven separate segments on thorax
• Paired appendages at end of abdomen called uropods

On the underside, females have leaf-like growths at base of some legs. These brood pouches hold developing eggs and embryos. The first two appendages on the male abdomen are modified as elongated copulatory organs.

Natural History

• Food
  Isopods are omnivores or scavengers feeding on dead or decaying plants or animals. Some may eat live plants.
• Habitat
  Isopods breathe with gills, so they are restricted to areas with high humidity, under rocks or logs, in leaf litter or in crevices. Some species are nocturnal.
• Predators
  Vertebrates and invertebrates.
• Interesting Behaviors
  Some species roll up into a ball when disturbed. Eggs (up to 100) are held in broad pouch on female. Juveniles look like adults and are soon liberated from pouch. Molting is in two stages. First the back half molts, then two to three days later, the front half molts. Coloration of both halves may be different at this time. Many species are fast walkers, but can be easily observed when held in the palm of the hand.

Impact on the Ecosystem

• Positive
  In their immediate vicinity, isopods do minimal soil improvement. Isopods are also a food source for other animals.
• Negative
  In greenhouses and southern states, large populations can eat and damage plants.
• Where to find them
  Look under logs, moist leaf litter, flower pots (a day after they have been watered), outdoor pet dishes, and under paving bricks or stones. Isopods live where it is moist and usually in a shaded area. To attract them, water soil or leaf litter in the shade and cover with plastic, piece of plywood or cardboard. Keep the area moist and check under the covering in a couple days

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