Propebela margaritae (I.P. Bogdanov, 1985)
Kurtziella margaritifera W.G. Fargo, 1953
Eucithara marginelloides (L.A. Reeve, 1846)
Propebela marinae I.P. Bogdanov, 1989
Mangelia martensi (H. Strebel, 1905)
Heterocithara marwicki (FOSSIL) P.A. Maxwell, 1988 †
Fusiguraleus marwicki (FOSSIL) (A.W.B. Powell, 1942 †)
Propebela marylandica (FOSSIL) E.J. Petuch, 1988 †
Oenopota maurellei W.H. Dall & P. Bartsch,1910
Apispiralia maxima C.F. Laseron, 1954
Heterocithara mediocris N.H. Odhner, 1924
Bela megastoma (FOSSIL) (G.A. Brugnone, 1862 †)
Pyrgocythara melita (W.H. Dall, 1919)
Mangelia melitensis C. Cachia & C. Mifsud,2008
Stellatoma mellissi (E.A. Smith, 1890)
Bela menkhorsti J.J. Van Aartsen, 1988
Tenaturris merita (R.B. Hinds, 1843)
Agathotoma merlini (P. Dautzenberg, 1910)
Agathotoma merlini concolor P. Dautzenberg, 1910
Vitricythara metria (W.H. Dall, 1903)
Oenopota metschigmensis (A. Krause, 1886)
Mangelia mica (R.A. Philippi, 1849)
Mangelia michaelseni (H. Strebel, 1905)
Agathotoma micromeris W.H. Dall, 1903
Mangelia micropleura (FOSSIL) R.J.L. Guppy, 1867 †
Pyrgocythara mighelsi (E.A. Kay, 1979)
Eucithara milia (R.A. Philippi, 1851)
Mangelia minuscula E.A. Smith, 1910
Bela minuta (L.A. Reeve, 1844)
Propebela miona (W.H. Dall, 1919)
Mangelia miorugulosa (FOSSIL) F. Kautsky, 1925 †
Mangelia miostriolata (FOSSIL) (Nordsieck, 1972 †)
Eucithara miriamica C. Hedley, 1922
Guraleus mitralis (A. Adams & G.F. Angas,1864)
Propebela mitrata (W.H. Dall, 1919)