Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Divasibranchia Minichev & Starobogatov, 1975
       Order Stylommatophora Schmidt, 1855 see Infraorder Stylommatophora Schmidt, 1855
         (Helicid Sigmurethra)
           Superfamily Arionoidea Gray, 1840
             Family Arionidae Gray, 1840
               Subfamily Arioninae Gray, 1840 see Family Arionidae Gray, 1840
                 Genus Arion Férussac, 1819
                   1 Subgenus Carinarion Hesse, 1926
                   2 Subgenus Kobeltia Seibert, 1873
                   3 Subgenus Mesarion Hesse, 1926
                   4 Subgenus Microarion Hesse, 1926