Tarrantoceras lillianense (FOSSIL) (Adkins 1928 †)
Mantelliceras lymense (FOSSIL) (Spath, 1926 †)
Mantelliceras mantelli (FOSSIL) (J. de C. Sowerby,1814 †)
Euomphaloceras merewetheri (FOSSIL) Cobban,Hook & J. Kennedy, 1989 †
Romaniceras mexicanum (FOSSIL) Jones, 1938 †
Sharpeiceras mexicanum (FOSSIL) Bose, 1928 †
Buccinammonites minimus (FOSSIL) J. Kennedy & Cobban,1990 †
Sharpeiceras minor (FOSSIL) J. Kennedy, Klinger& Lehmann, 2015 †
Neocardioceras minutum (FOSSIL) Cobban, 1988 †
Paraburoceras minutum (FOSSIL) Cobban,Hook & J. Kennedy, 1989 †
Cryptometoicoceras mite (FOSSIL) J. Kennedy & Cobban,1990 †
Sharpeiceras mocambiquense (FOSSIL) Choffat, 1903 †
Mammites mohavanensis (FOSSIL) Böse, 1923 †
Paramammites mohovanensis (FOSSIL) (Böse, 1920 †)
Metoicoceras mosbyense (FOSSIL) Cobban, 1953 †
Benueites mosquerae (FOSSIL) (D.L.G. Karsten, 1886 †)
Acanthoceras muldoonense (FOSSIL) Cobban & P.H. Scott,1973 †
Tarrantoceras multicostatum (FOSSIL) (Adkins, 1928 †)
Mammites mutabilis (FOSSIL) Reyment, 1955 †
Nannometoicoceras nanos (FOSSIL) J. Kennedy & Cobban,1990 †
Calycoceras naviculare (FOSSIL) (Mantell, 1822 †)
Pseudovascoceras nigeriense (FOSSIL) (Woods, 1911 †)
Mammites nodosoides (FOSSIL) (F. Schlüter, 1871 †)
Cunningtoniceras novimexicanum (FOSSIL) Cobban,Hook & J. Kennedy, 1989 †
Jeanrogericeras obliquus (FOSSIL) (Karrenberg, 1935 †)
Watinoceras odonnelli (FOSSIL) Cobban,Hook & J. Kennedy, 1989 †
Acanthoceras offarcinatum (FOSSIL) White, 1887 †
Calycoceras orientale (FOSSIL) E. Matsumoto & al.,1957 †
Newboldiceras orientale (FOSSIL) Thomel 1972 †
Yubariceras ornatissimum (FOSSIL) (F. Stoliczka, 1864 †)
Yubariceras otatumei (FOSSIL) (E. Matsumoto, H. Saito& Fukada, 1957 †)
Jeanrogericeras pachycostatus (FOSSIL) Summesberger, 1992 †
Pseudaspidoceras paganum (FOSSIL) Reyment, 1954 †
Dunveganoceras parvum (FOSSIL) Cobban, 1953 †
Acanthoceras peltoceroides (FOSSIL) Pavlow & Lamplugh, 1892 †