> Was it the same insect in a different stage of > development or a different insect? You probably already know but just forgot that these aren't insects at all, but crustaceans. While insects have 6 legs (3 pair of thoracic appendages), isopod crustaceans have 7 pair of leg- like thoracic appendages (pereiopods). While most crustaceans are marine (crabs, shrimps, lobsters, copepods, ostracods, barnacles, etc) or at least aquatic (crayfish, water fleas, etc.) isopods are unusual in including terrestrial, aquatic, and marine members. The majority of isopod species are marine. Species of the genus Idothea are not uncommonly found in the intertidal zone along our coasts. Some people (like me) use the terms sow bugs and pill bugs more or less interchangably for the terrestrial isopod species you mention. Others distinguish sow bugs, which don't roll up into a ball, from pill bugs, which do roll into a ball. According to Acorn and Sheldon's Bugs of Washington and Oregon, both sow bugs (Oniscus aselus) and pill bugs (Armadillidium vulgare) are introduced from Europe. I find that shocking, considering how abundant they are in most urban gardens, but come to think of it, I guess they aren't so common out in the woods. Paul Talbert Hillman City, Seattle, WA email@example.com
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