Mercuria meridionalis (A. Risso, 1826)
Pyrgulopsis merriami H.A. Pilsbry & C.E. Beecher,1892
Austropyrgus mersus A. Clark, W.B. Miller& W.F. Ponder, 2003
Beddomeia mesibovi W.F. Ponder & K.B. Clark,1993
Pseudamnicola messapica (FOSSIL) D. Esu & O. Girotti,2010 †
Pyrgulopsis metcalfi D.W. Taylor, 1987
Hydrobia metochiana (FOSSIL) P.S. Pavlovic, 1932 †
Micromelania metochiana (FOSSIL) Miloševic, 1971 †
Kuschelita mica F.M. Climo, 1974
Cincinnatia mica F.G. Thompson, 1968
Pseudotryonia mica R. Hershler, H.X. Liu& J.J. Landye, 2011
Lobogenes michaelis H.A. Pilsbry & C.E. Beecher,1927
Bythiospeum michaelleae H. Girardi, 2002
Bythiospeum michaudi (É.A.A. Locard, 1882)
Phreatodrobia micra (H.A. Pilsbry& J.H. Ferriss, 1906)
Reesidella micra (FOSSIL) Pan, 1977 †
Saxurinator microbeliscus H. Schütt, 1968
Pyrgulopsis micrococcus (H.A. Pilsbry, 1893)
Alzoniella microstoma M. Bodon & S. Cianfanelli,2002
Socenia microtesta (FOSSIL) (Papp, 1954 †)
Islamia mienisi (H. Schütt, 1991)
Euxinipyrgula milachevitchi (A.N. Golikov& Y.I. Starobogatov, 1966)
Ohrigocea miladinovorum S. Hadžišce, 1959
Caspia milae H.D. Boeters, P. Glöer& D.G. Georgiev, 2015
Goniochilus milicevici (FOSSIL) (P.S. Pavlovic, 1927 †)
Pyrgulopsis militaris R. Hershler, 1998
Pyrgulopsis millenaria R. Hershler, 1998
Victodrobia millerae W.F. Ponder & K.B. Clark,1993
Pyrgulopsis milleri R. Hershler & H.P. Liu,2010
Belgrandiella mimula M. Haase, 1996
Petterdiana minima (W.F. Petterd, 1889)
Pseudamnicola minima (FOSSIL) (Lörenthey, 1893 †)
Micromelania minima (FOSSIL) P.S. Pavlovic, 1927 †
Pauluccinella minima (M. Paulucci, 1881)
Pyrgulopsis minkleyi (D.W. Taylor, 1966)