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 Orthalicoidea Martens, 1860
               Family Urocoptidae Pilsbry, 1898 (1868), nom. inq.
                 Subfamily Holospirinae Pilsbry, 1946
                   Genus Coelostemma Dall, 1895
                     1 Subgenus Apertaxis Pilsbry, 1953
                     2 Subgenus Crycoryne Thompson, 1971
                     3 Subgenus Styloptyx Thompson, 1971