They include such things as spiders, leeches, millipedes, pill bugs, flatworms, mites, beetles, and water dwellers such as water scorpions and nematode worms.
The Crustaceamorpha includes lobsters, crabs, shrimp, pill bugs, krill, barnacles, water fleas, brine shrimp (sea monkeys), copepods, ostracods, and more - many, many more.
This small crustacean is similar to the terrestrial pill bug but is aquatic and is found in only one thermal spring near Socorro, New Mexico.
The wood louse is known in Britain by many local names - tiggy-hog, cheeselog, pill bug, chiggy pig, and rolypoly among others.
In areas where acid rain is most severe, the supplementary calcium-rich foods that female songbirds depend on - snail shells, isopods such as pill bugs, millipedes, and earthworms - may be in short supply.