These are pill bugs, notice the difference
The
pill bug (also called the wood louse and the roly-poly bug) is a small,
segmented land creature that can roll into a tiny ball for protection.
The pill bug is NOT an insect, but is an isopod (another type of arthropod).
Where to find
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. Traps made by hollowing out apples or potatoes may be used to catch them. Keep the area moist and check under the covering in a couple days. If you are unable to find isopods they can be purchased from: Carolina Biological Supply Company.
How to collect
Before looking for isopods, prepare a container and tools to gather the isopods. To collect them, use a spoon or shovel and a container. Look under a rock or log and be prepared to collect the isopods quickly before they scurry away from the light. Gently scoop up soil with the isopods and place them in the container. Look on the underside of the log or stone for others. They can be gently picked or brushed off with a finger into the container. Pill bugs often curl up and can be picked up individually or scooped up with the spoon. If you are going to keep the isopods a couple days before placing them in the classroom, use a plastic container with small holes poked in the lid and a moistened piece of paper towel or sponge lightly crumples inside. Use an old pie tin to sort the isopods from the soil before placing them in the container. The paper towel must be kept moist or they will die. When you are looking under rocks and logs be careful to avoid scorpions, centipedes and other animals that live there. Return the rock or log to the way it was when you found it.
How to Keep
A raw potato can be provided for food. Food should be removed if it shows any sign of mold and replaced with sliced carrot, potato, or apple.
If you are keeping them for a longer period of time, place them in a terrarium with rich, moist soil. Place moist paper towels in the container to provide humidity. Continue to add vegetables, replacing them as necessary to control mold. Keep container at room temperature in low light.
Classroom habitat. Isopods are excellent classroom animals—they exhibit interesting behaviors, they are small but not tiny, they don’t bite, smell, fly, or jump, and they are easy to care for. Isopods can live in just about any vessel, from a recycleasd margarine tub to a 50-liter aquarium. If the container is smooth-sided, it doesn’t even have to be covered, because isopods can’t climb smooth surfaces at all. A layer of soil covered with some dead leaves, twigs, and bark is great, but isopods will be comfortable with some paper towels or newspaper laid on the soil. They do like to have some structure to crawl under.
Food and water. The most important thing to remember is that the soil must be kept moist at all times—not wet, but moist—so that the isopods don’t dry out. A chunk of raw potato in the container with the isopods serves as a source of both food and moisture. Otherwise they will eat the decomposing leaves and twigs or the paper towels and newspaper.
Ecology
Woodlice need moisture because they breathe through gills, called pseudo trachea, and so are usually found in damp, dark places, such as under rocks and logs. They are usually nocturnal and are detritivores,
feeding mostly on dead plant matter. Woodlice then recycle the
nutrients back into the soil. In artificial environments such as
greenhouses where it can be very moist, woodlice may become abundant and
damage young plants, such as ferns.The woodlouse has a shell-like exoskeleton, which it must progressively shed as it grows. The moult takes place in two stages; the back half is lost first, followed two or three days later by the front. This method of moulting is different from that of most arthropods, who shed their cuticle in a single process.
A female woodlouse will keep fertilized eggs in a patch on the underside of her body until they hatch into small, pink offspring. The mother then appears to "give birth" to her offspring.
Some species of woodlice are able to roll into a ball-like form when threatened by predators, leaving only their armoured back exposed. This ability, or dominant behavior, explains many of the woodlouse's common names.
Metabolic rate is temperature dependent in woodlice. In contrast to mammals and birds, invertebrates are not "self heating": the external environmental temperature relates directly to their rate of respiration.
They are not generally regarded as a serious household pest as they do not spread disease and do not damage wood or structures; however, their presence can indicate dampness problems.
Habitat and Distribution:
Pill bugs are common invertebrates that are found in many biomes around the world, including temperate forests, rainforests, and grasslands. They prefer moist areas, often living in soil and under decaying leaves, rocks, and dead logs.
Life Cycle:
A pill bug begins its life as a tiny egg. The young pill bug looks almost like a miniature adult. As it grows, it molts (sheds its old, outgrown exoskeleton) 4 to 5 times.
Anatomy:
Pill bugs are covered by a hard exoskeleton (also called the cuticle) made from chitin. They have three basic body parts, the head (which is fused to the first segment of the thorax), the thorax (the 7 segments of the thorax that are not fused to the head are called the pereon), and the abdomen (which is also called the pleon). Pill bugs have 7 pairs of jointed legs and 2 pairs of antennae (but one pair is barely visible). The antennae, mouth and eyes are located on the head. A pair of abdominal uropods are at the posterior end of the pill bug, but only the terminal exopods are visible from the top of the pill bug. Pill bugs are less than an inch long.
Diet: Pill bugs eat decaying plants and animals and some living plants.
Predators: Pill bugs are eaten by many animals. Their main protection is rolling into an armored ball.
Classification: Kingdom Animalia (animals), Phylum Arthropoda, Subphylum Crustacea, Class Malacostraca, Order Isopoda (isopods), Family Armadillidiidae, Genus Armadillidium, Oniscus, etc. Many species, including A. vulgare (the common pillbug).