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
         (Achatinid Sigmurethra)
           Suborder Sigmurethra Pilsbry, 1900 see Group Sigmurethra Pilsbry, 1900
             Superfamily Streptaxoidea Gray, 1860 [monotypic]
               Family Streptaxidae Gray, 1860
                 Subfamily Enneinae Bourguignat, 1883
                   01 Genus Ennea Adams & Adams, 1855
                   02 Genus Acanthenna Vaught, 1989, orth. inval. see Genus Acanthennea Martens, 1898
                   03 Genus Bruggennea Dance, 1972
                   04 Genus Diaphera Albers, 1850
                   05 Genus Elma Adams, 1866
                   06 Genus Gibbulinella Wenz, 1920
                   07 Genus Gibbus Montfort, 1810
                   08 Genus Gonidomus Swainson, 1840
                   09 Genus Gonospira Swainson, 1840
                   10 Genus Gulella Pfeiffer, 1856
                   11 Genus Parennea Pilsbry, 1919
                   12 Genus Pseudelma Kobelt, 1904
                   13 Genus Ptychotrema Mörch, 1852
                   14 Genus Pupiginella Vaught, 1989, orth. inval. see Genus Pupigulella Pilsbry, 1919
                   15 Genus Sinoennea Kobelt, 1904
                   16 Genus Stereostele Pilsbry, 1919
                   17 Genus Streptostele Dohrn, 1866
                   18 Genus Varicostele Pilsbry, 1919