While poking around in the yard today, I saw a lot of pillbugs, including 2 or 3 metallic blue ones among scores of the usual dark gray ones.
While poking around on google today looking for blue pillbug info, I learned these cool pillbug facts:
- Pillbugs and sowbugs are not insects. They are isopods, part of the class Crustacea, which is comprised mainly of marine animals with a calcareous exoskeleton and jointed appendages (such as crabs). Isopods are just about the only terrestrial Crustacea; the rest of the species live in water.
- If it rolls up when you poke it, it's a pillbug. If it doesn't, it's a sowbug.
- The act of rolling into a ball is called conglobulation.
- Female isopods have a marsupium, a brood pouch in which the eggs are incubated until they hatch. I thought only marsupials like possums and kangaroos had a brood pouch.
Here's a pic of one of the blue pillbugs on a rock:
It's blue, all right:
Here are the usual grays, for comparison:
Since these creatures are known by many names, I am inspired to write a haiku about them:
pillbugs and sowbugs,
what is in a name?
ETA: The mystery might be solved.
Edit: Blue pillbugs are infected with the Isopod Iridescent Virus, or iridovirus, which causes the exoskeleton and internal organs to become blue, violet or purple. The virus eventually effects the health of the animals.