Isopods
Isopod means "same foot", a reference to the similar legs that are evident in the illustrations, as opposed to amphipods. Isopods are the most widespread of all arthropods, found from the highest mountaintops to the deepest seas. Most isopods are small, although some deep-sea types grow to over a foot in length. Isopods are mainly harmless scavengers, although some are parasites, and larger types can pack a painful bite.
The most well-known type of isopod is the common terrestrial Pill Bug or Sow Bug (shown) which can be found under any rock or log. Marine pillbugs are very similar to their land-dwelling cousins.