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BugGuide is a National Moth Week Partner. How to add your National Moth Week 2021 photos. July 17-25.

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

National Moth Week 2020 photos of insects and people.

Photos of insects and people from the 2019 BugGuide Gathering in Louisiana, July 25-27

Discussion, insects and people from the 2018 gathering in Virginia, July 27-29

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Previous events


Order Isopoda - Isopods

Wood Louse 1316 - Armadillidium Idotea pill - Armadilloniscus Painted Woodlouse - Porcellio spinicornis Ligia exotica?  - Ligia Woodlouse - Porcellio scaber SBBG-SCL-TIC_000223 - Armadillidium vulgare Ligia
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Crustacea (Crustaceans)
Class Malacostraca (Malacostracans)
Superorder Peracarida (Peracarida (Amphipods and Isopods))
Order Isopoda (Isopods)
Other Common Names
cressbug, pillbug, sowbug, woodlouse, rock slater, roly-poly
>10,200 spp. worldwide(1)
2 to >300 mm (Bathynomus, a deep sea genus)
key to OH spp. in(2)
Worldwide, from the deep sea to terrestrial habitats.
Pillbugs and sowbugs, being crustaceans, breathe by means of gills. This is why they need moisture, but they will drown if submerged
Print References
Richardson, H. 1905. A monograph on the isopods of North America. Bulletin of the United States National Museum. 54: i–liii, 1-727, 740 figs.(3)
Internet References
Coastal Isopods of California (Brusca et al. 2001)
Taxon profile (Brusca 1997)