Looks like a pill bug but doesn’t seem to be
April 13, 2010
Dear What’s That Bug!,
Today I found the bug in the attached photo when I was pulling a weed against my foundation. They seemed to be going into the brick wall, where my bedroom is. The bugs are about a quarter to a half inch long and very shy.
I wouldn’t normally be concerned, but a few days ago I found one dead in the other side of the house (not near a wall), on carpet that has only been installed for two weeks.
I thought it was a pill bug, but it doesn’t seem to match the pictures of other pill bugs very well.
The one picture shows some tiny ants just above it (going into my house too…) there may be a symbiosis there to help with identification.
Thanks very much!
WBTtheFROG (we eat what bugs us)
Pittsburgh, Pennsylvania, USA
We will attempt to go from general to specific with our response. In a most general sense, this is a Woodlouse in the suborder Oniscidea, of the Isopod order Isopoda, which is classified as the subphylum Crustacea in the phylum Arthropoda, which contains insects and their relatives. The suborder Oniscidea (which is represented on BugGuide) contains several families, including the Pillbugs in the family Armadillidiidae which can roll into balls. Also in that suborder are several other families with members that cannot roll into balls. BugGuide says this of the family Sowbug Oniscidae: “Sowbugs all have tails (uropods) that extend beyond their last abdominal segment. Most cannot roll into a ball. This family has three segments in the small, segmented end of the long antennae, while the Porcellionidae Family has only two segments.” Your critter has uropods, and it appears to have three segments at the end of the antennae. The only member of the family illustrated on BugGuide is the European Sowbug, and it is reported to be: “Not harmful to humans, rather helpful in cleaning up plant waste etc. Occasionally reported to eat garden plants, but generally considered beneficial.”