Labyrinthus magdalenensis G.A. Solem, 1966 Colombia
Xanthomelon magnidicum (T. Iredale, 1938) Australia, Dingo Beach43 mm
Discoconcha majuscula (L. Pfeiffer, 1856) Papua New Guinea31 mm
Papuina malantanensis A. Adams & G.F. Angas,1876 Solomon Islands, Malanta Island21,4 mm
Chloritis malayana (O.F. von Möllendorff,1887) Western Australia
Chloritis malbatensis (J.G. Hidalgo, 1890)
Camaena mamilla (A.E.J. Férussac, 1821) Indonesia, Sulawesi51,5 mm
Camaena mamilla crassiventris B. Rensch, 1933 Indonesia, Central Sulawesi57,5 mm
Mandarina mandarina (G.B. I Sowerby, 1839) Japan, Ogasawara Islands
Semotrachia mannensis T. Iredale, 1937 South Australia
Chloritis mansonensis (G.P.L.K. Gude, 1906) Vietnam, Tonkin
Ventopelita mansueta (L.A. Reeve, 1854) Australia, Richmond
Camaena mansuyi P. Dautzenberg& H. Fischer, 1906 Vietnam, Ha-Giang37,1 mm
Camaena mansuyi depressa P. Dautzenberg& H. Fischer, 1906 Vietnam, Tonkin28,5 mm
Labyrinthus manueli H.C. Higgins, 1872 Ecuador25,5 mm
Galadistes marcescens (J.C. Cox, 1868) Australia, Clarence River
Cupedora marcidum (C. Hedley, 1912) New South Wales
Succochlea maretensis F. Criscione & F. Köhler,2014
Obba marginata (O.F. Müller, 1774) Malaysia, Borneo30 mm
Amphidromus mariae Thach & F. Huber, 2017
Amphidromus mariasendersae Thach & F. Huber, 2017
Amphidromus marieabbasae Thach, 2017
Chloritis marimberti A.R.J.B. Bavay& P. Dautzenberg, 1900 Vietnam, Cho-Ra17,3 mm
Chloritis marimberti carinata A.R.J.B. Bavay& P. Dautzenberg, 1909 Vietnam, Muong-Kong19,1 mm
Labyrinthus marmatensis H.A. Pilsbry, 1910 Colombia42 mm
Badistes marshalli A. McLauchlan, 1951 New South Wales
Sinumelon marshalli T. Iredale, 1938 Queensland
Amphidromus martensi O. Böttger, 1894 Malaysia, Borneo44 mm
Ganesella martini (FOSSIL) C.H. Oostingh, 1935 † Indonesia, Jawa Tengah, Temanggung
Amphidromus masoni (H.H. Godwin-Austen,1876)
Camaena massiei (L.J. Morlet, 1891) Vietnam, Tonkin
Badistes mastersi J.C. Cox, 1864 New South Wales
Figuladra mattea (T. Iredale, 1933) Australia, Yeppoon28 mm
Cooperconcha mawsoni (T. Iredale, 1937) South Australia12,5 mm
Noctepuna mayana (C. Hedley, 1899) Queensland