Persicula margotae R. Le Béon, 2015
Intelcystiscus mariae J. Espinosa & J.A. Ortea,2014 Cuba
Crithe marianoi T. Cossignani, 2001
Gibberula marinae A. Wakefield& T. McCleery, 2004 Fiji Islands2,48 mm
Gibberula marioi J. Espinosa & J.A. Ortea,2000 Costa Rica, Manzanillo
Gibberula mariscali J. Espinosa & J.A. Ortea,2007
Cystiscus marshalli F. Boyer, 2003 New Caledonia1,8 mm
Gibberula martinae T. Cossignani, 2001
Gibberula martingaiteae J.A. Ortea, 2015
Ticofurcilla maryolisae Ortea, 2016
Persicula masirana B. Roth & R.E. Petit,1972 Oman, Masirah Island8 mm
Cystiscus maskelynensis A. Wakefield& T. McCleery, 2006 Vanuatu Island, New Hebrides1,6 mm
Cystiscus matoensis A. Wakefield& T. McCleery, 2006 New Caledonia, Mato Island1,94 mm
Gibberula mauritiana T. Cossignani, 2011 Mauritius3,8 mm
Gibberula mazagonica (J.C. Melvill, 1893) Oman3 mm
Cystiscus melwardi S. Gofas, 1992 Australia, Port Hedland4 mm
Gibberula mendacis S. Gofas, 1989 Angola2,1 mm
Gibberula metula (B.C. Cotton, 1949)
Cystiscus microgonia (W.H. Dall, 1927)
Gibberula microscopica C.M. Tapparone-Canefri,1875
Gibberula miliaria (C. Linnaeus, 1758) Italy, Cannizzaro5 mm
Gibberula mimetica S. Gofas, 1989 Angola2,4 mm
Cystiscus minor F. Boyer, 2003 West America
Canalispira minor (W.H. Dall, 1927) USA, Georgia
Cystiscus minusculus M. Lussi & G. Smith, 1998 South Africa, Agulhas Bank2,6 mm
Cystiscus minutissimus (J.E. Tenison-Woods,1876) Australia, Ulladulla3 mm
Persicula mirandana (FOSSIL) F. Hodson, 1927 † Venezuela, Zulia, Miranda
Gibberula modica S. Gofas & F. Fernandes,1988 Sao Tomè Island3,2 mm
Cystiscus moerchi (J.H. Redfield, 1870)
Cystiscus montrouzieri (A.R.J.B. Bavay, 1922) New Caledonia1,5 mm
Cystiscus mosaica A. Wakefield& T. McCleery, 2005 Tuamotu1,5 mm
Gibberula moscatellii F. Boyer, 2004 Brazil, Rio Grande do Norte12,7 mm
Cystiscus multidentatus W.L. May, 1920 Australia, Twofold Bay3 mm
Persicula multilineata (G.B. II Sowerby, 1846) Netherlands Antilles
Plesiocystiscus myrmecoon (W.H. Dall, 1919)