Leiosolenus lima (É. Lamy, 1919)
Mytilaster lineatus (J.F. Gmelin, 1791)
Septifer lineatus (FOSSIL) (J. de C. Sowerby) †
Amygdalum lineum C. Hedley, 1906
Lithophaga lingua (FOSSIL) Gardner, 1916 †
Septifer lingua (FOSSIL) Martin, 1879 †
Lithophaga lingualis (FOSSIL) Phillips †
Modiolus lingualis (FOSSIL) Phillips, 1836 †
Mytilus linguatulus (FOSSIL) R. Tate, 1887 †
Arcoperna linteata (FOSSIL) D.T. Dockery, 1982 †
Leiosolenus lischkei M. Huber, 2010
Lithophaga lithophaga (C. Linnaeus, 1758)
Lithophaga lithura H.A. Pilsbry, 1905
Mytilus littoralis (FOSSIL) Slodkewitsch, 1936 †
Adipicola longissima (K.H.J. Thiele& S.G.A. Jaeckel, 1931)
Amygdalum longum (FOSSIL) (H.G. Bronn, 1831 †)
Gregariella lornensis (FOSSIL) (C.R. Laws, 1932 †)
Mytilus luciferus (FOSSIL) M. Yokoyama, 1924 †
Modiolus lulat (P. Dautzenberg, 1891)
Ciboticola lunata (C. Hedley, 1902)
Lycettia lunularis (FOSSIL) (J. Lycett, 1857 †)
Lithophaga lycetti (FOSSIL) J.J.F. Whiteaves, 1861 †
Mytilus mabuchii (FOSSIL) K. Oyama & A. Mizuno,1958 †
Idas macdonaldi R.G. Gustafson, R.D. Turner, R.A. Lutz& R.C. Vrijenhoek, 1998
Mytilus madagascariensis (FOSSIL) R.B. Newton, 1895 †
Crenella magellanica K. Linse, 2002
Mytilus magellanicus (FOSSIL) Chemntiz, 1785 †
Septifer magnificus (FOSSIL) Krishtofovich, 1969 †
Modiolus magnus (FOSSIL) Guskov, 1984 †
Lithophaga maikaensis (FOSSIL) J. Marwick, 1953 †
Promytilus maiyensis (FOSSIL) Nakazawa & Newell, 1968 †
Leiosolenus malaccana (L.A. Reeve, 1857)
Rhomboidella malaccana K.W. Ockelmann, 1983
Modiolus mandannaensis (FOSSIL) Lees, 1934 †
Xenostrobus mangle (K.W. Ockelmann, 1983)