M.G. Waldvogel, Extension Entomology Specialist. Oniscus asellus Linnaeus, Porcellio scaber Latreille Description Sowbug and pillbug adults are 5 to 10 mm in length, with segmented, slightly flattened bodies. Sowbugs have two tail-like structures on the rear end. Pillbugs lack these structures. There are seven pairs of legs and no antennae.
Eyes are well developed.
Sowbugs and pillbugs are more closely related to lobster and crayfish than to insects. The tiny eggs are carried by the female in a pouch underneath her body. No description of the eggs is available. Young sowbugs and pillbugs resemble the adults but are smaller and paler. Biology Sowbugs and pillbugs are common throughout the Southeast.