Phylum Mollusca Linnaeus, 1758 - molluscs
   Class Gastropoda Cuvier, 1795 - snails and slugs
     Subclass Heterobranchia Burmeister, 1837 [monotypic] see Superorder Heterobranchia Burmeister, 1837
       Order Heterostropha Fischer, 1885
         Superfamily Architectonicoidea Gray, 1850
           Family Mathildidae Dall, 1889
             1 Genus Mathilda Semper, 1865
             2 Genus Acrocoelum Cossmann, 1888
             3 Genus Clathrobaculus Cossmann, 1912
             4 Genus Gegania Jeffreys, 1884
             5 Genus Granulicharilda Kuroda & Habe, 1971
             6 Genus Mathildona Iredale, 1929
             7 Genus Opimilda Iredale, 1929
             8 Genus Turritellopsis Sars, 1878