Brachidontes tenuistriatus (R.W. Dunker, 1853)
Modiolus tenuistriatus (FOSSIL) Slodkewitsch, 1936 †
Lithophaga teres (R.A. Philippi, 1846)
Perna tetleyi (FOSSIL) (Powell & J.A. Bartrum,1929 †)
Mytilon theresae (FOSSIL) Marincovich Jr., 1993 †
Bathymodiolus thermophilus Kenk & Wilson, 1985
Tumidimytilus tichanovichi (FOSSIL) J. Makiyama, 1934 †
Tumidimytilus tichanovitchi (FOSSIL) (J. Makiyama, 1934 †)
Falcimytilus tigrensis (FOSSIL) (Blanford, 1870 †)
Mytilus tochilnensis (FOSSIL) A.I. Kafanov, 1987 †
Brachidontes toechophora (FOSSIL) Boettger, 1883 †
Septifer torquatus (FOSSIL) (P. Marshall, 1918 †)
Modiolus traillii (L.A. Reeve, 1857)
Mytilus trampasensis (FOSSIL) Clark †
Modiolus transparens (FOSSIL) L. Waagen, 1881 †
Modiolus trigonalis (FOSSIL) Slodkewitsch, 1936 †
Nodomytilus trigonimimus (FOSSIL) Kauffman & H.A. Leanza,2004 †
Leiosolenus tripartitus (F.P. Jousseaume, 1894)
Arcuatula tristis (R.W. Dunker, 1857)
Mytilus trossulus Gould, 1850
Zelithophaga truncata (Gray, 1843)
Modiolus tulipea (FOSSIL) J.B.P.A. Lamarck, 1819 †
Modiolus tumbezensis H.A. Pilsbry & A.A. Olsson,1935
Falcimytilus tumidus (FOSSIL) (Morris & J. Lycett,1853 †)
Botula tumiensis (FOSSIL) Lautenschlägerin Krishtofovich, 1964 †
Modiolus typicus (FOSSIL) E. Forbes, 1846 †
Brachidontes undulatus (R.W. Dunker, 1857)
Modiolus undulatus (FOSSIL) (Forbes) †
Mytilus ursensis (FOSSIL) Smith, 1927 †
Brachidontes ustulatus (J.B.P.A. Lamarck, 1819)
Modiolus utcholokensis (FOSSIL) Slodkewitsch, 1936 †
Arenifodiens vagina (J.B.P.A. Lamarck, 1819)
Rhomboidella vaillanti (A. Issel, 1869)
Brachidontes variabilis (FOSSIL) (C.F.F. von Krauss,1848 †)
Musculus varicosus (A.A. Gould, 1844)