Pupilloidea

They are characterized by their small, often cylindrical, ovate, or elongate shells. Their shells can range from smooth to ribbed or striated. They are generally tiny, ranging from a few millimeters to about a centimeter in length. The aperture often has denticles (teeth) or lamellae, which may play roles in predator deterrence or structural support. The margin of the aperture often features a well-defined peristome, sometimes thickened or reflected. ==Distribution==

Species in this superfamily are cosmopolitan, found on every continent except Antarctica. They can be found in dry and arid regions to temperate forests and even tropical zones. ==Taxonomy==

This superfamily contains the following families: • Achatinellidae Gulick, 1873 • Agardhiellidae Harl & Páll-Gergely, 2017 • Amastridae Pilsbry, 1910 • Argnidae Hudec, 1965 • Cerastidae Wenz, 1923 • Cochlicopidae Pilsbry, 1900 (1879) • Draparnaudiidae Solem, 1962 • Enidae B. B. Woodward, 1903 (1880) • Fauxulidae Harl & Páll-Gergely, 2017 • Gastrocoptidae Pilsbry, 1918 • Hypselostomatidae Zilch, 1959 • Lauriidae Steenberg, 1925 • Odontocycladidae Hausdorf, 1996 • Orculidae Pilsbry, 1918 • Pagodulinidae Pilsbry, 1924 • Partulidae Pilsbry, 1900 • Pleurodiscidae Wenz, 1923 • Pupillidae W. Turton, 1831 • Pyramidulidae Kennard & B. B. Woodward, 1914 • Spelaeoconchidae A. J. Wagner, 1928 • Spelaeodiscidae Steenberg, 1925 • Strobilopsidae Wenz, 1915 • Valloniidae Morse, 1864 • Vertiginidae Fitzinger, 1833 Synonyms • Cerastuidae Wenz, 1930: synonym of Cerastidae Wenz, 1923 • Chondrulidae A. J. Wagner, 1928: synonym of Chondrulini Wenz, 1923 (junior synonym) • Cionellidae L. Pfeiffer, 1879: synonym of Cochlicopidae Pilsbry, 1900 (1879) • Elasmiatidae Kuroda & Habe, 1949: synonym of Elasmiatini Kuroda & Habe, 1949 (original rank) • Family Pachnodidae Steenberg, 1925: synonym of Cerastidae Wenz, 1923 • Pupidae J. Fleming, 1822: synonym of Cerionidae Pilsbry, 1901 (invalid: type genus a junior homonym of Pupa Röding, 1798 [Acteonidae]) • Pupisomatidae Iredale, 1940: synonym of Valloniidae Morse, 1864 • Pupoididae Iredale, 1939: synonym of Pupillidae W. Turton, 1831 • Strobilidae Jooss, 1911: synonym of Strobilopsidae Wenz, 1915 (invalid: type genus a junior homonym of Strobila M. Sars, 1829 [Cnidaria]) • Tornatellinidae Sykes, 1900: synonym of Tornatellininae Sykes, 1900 (original rank) • Zuidae Bourguignat, 1884: synonym of Cochlicopidae Pilsbry, 1900 (1879) ==References==