Porcellionidae, Trachelipodidae, Cylisticidae. A Porcellio scaber B Porcellionides pruinosus C Porcellio spinicornis, head, dorsal view D Trachelipus rathkii, head, dorsal view E Porcellio laevis, head and first pereonal tergite, dorsal view F Cylisticus convexus, head and first pereonal tergite, dorsal view.