Ancylastrum mooiensis B. Walker, 1912 Central Africa
Planorbis moquini E. Réquien, 1848 Algeria
Ancylus moravicus (FOSSIL) Rzehak, 1893 †
Hebetancylus moricandi (A.V.M.D. D'Orbigny,1837) Brazil, Rio Grande do Sul
Atopippeutis muelleri (FOSSIL) D. Kadolsky, 2015 † Germany, Bayern
Gyraulus multicingulatus (W.A. Wenz, 1919)
Gyraulus multiformis (Zeiten, 1832) Arizona, Coconino County
Planorbella multivolvis W. . Case, 1847 Michigan
Bulinus mutandensis H.B. Preston, 1913 Uganda
Ancylastrum nana B. Walker, 1912 South Africa
Bulinus nasutus E.C. Von Martens, 1879 Fiji Islands
Ferrissia natalensis B. Walker, 1924 South Africa
Bulinus natalensis H.C. Küster, 1841 Kenya
Afrogyrorbis natalensis (C.F.F. von Krauss, 1848) South Africa, Natal14 mm
Gyraulus nautiliformis (Gozhik & Prysjazhnjuk,1978)
Gyraulus nedici (Š. Brusina, 1902)
Gyraulus nedyalkovi P. Glöer & D.G. Georgiev,2012 Turkey, Icel
Gyraulus nematophorus (Š. Brusina, 1902)
Ferrissia neozelanica (H.H. Suter, 1905) New Zealand, Christchurch
Ferrissia neumayri (FOSSIL) (C.F. Fontannes, 1881 †)
Parapholyx nevadensis J. Henderson, 1934 Nevada, Pyramid Lake
Helisoma newberryi H.C. Lea, 1858 Nevada5 mm
Helisoma newberryi occidentalis G.D. Hanna, 1924 California, Eagle lake16,6 mm
Isidorella newcombi (A. Adams & G.F. Angas,1864) South Australia
Biomphalaria nicaraguana (P.M.A. Morelet, 1851) Nicaragua
Helisoma nigricans (J.B. von Spix, 1827) Florida
Anisus nikolensis (W. Dybowski, 1913)
Laevapex nipponica J.T. Kuroda, 1947 Taiwan
Camptoceras nipponica B. Walker, 1919 Japan
Planorbis nisseanus (FOSSIL) P.S. Pavlovic, 1931 †
Segmentina nitida (O.F. Müller, 1774) Belgium5 mm
Polypylis nitidella (E.C. Von Martens, 1877) Japan, Hyogo
Drepanotrema nordestense (I.D. Lucena, 1954) Brazil, Paraná
Gyraulus novaki (Š. Brusina, 1897)
Anisus noziriensis A. Mori, 1938 Japan, Sagami Bay