Ligumia subrostrata (T. Say, 1831)
Fusconaia subrotunda (I. Lea, 1831)
Fusconaia subrotunda lesueuriana (I. Lea, 1840)
Obovaria subrotunda (C.S. Rafinesque, 1820)
Radiatula substriata (I. Lea, 1856)
Ptychobranchus subtentum (T. Say, 1825)
Strophitus subvexus T.A. Conrad, 1834
Lasmigona subviridis (T.A. Conrad, 1835)
Amphinaias succissa (I. Lea, 1852)
Rectidens sumatrensis (R.W. Dunker, 1852)
Unionelloides suni (FOSSIL) (Chow, 1953 †)
Physunio superbus (I. Lea, 1843)
Rhombuniopsis superstes (M. von Neumayr, 1899)
Nephronaias tabascoensis (J.G.F. de Charpentierin H.C. Küster, 1856)
Villosa taeniata (T.A. Conrad, 1829)
Pleurobema taitianum I. Lea, 1834
Cyrtonaias tampicoensis (I. Lea, 1838)
Pseudospatha tanganyicensis (E.A. Smith, 1880)
Sphenonaias taumilapana (T.A. Conrad, 1855)
Rhombuniopsis tauriformis (H.C. Fulton, 1906)
Parreysia tavoyensis (A.A. Gould, 1843)
Saharella tedreftensis (FOSSIL) D. Mongin, 1963 †
Popenaias tehuantepecensis (J.C.H. Crosse& P.H. Fischer, 1893)
Nephronaias tempisquensis H.A. Pilsbry, 1920
Cristaria tenuis (E. Griffith & E. Pidgeon,1833)
Lampsilis teres C.S. Rafinesque, 1820
Nitia teretiuscula (R.A. Philippi, 1847)
Unio terminalis J.R. Bourguignat, 1852
Unio terminalis delicatus (I. Lea, 1863)
Uniomerus tetralasmus (T. Say, 1831)
Toxolasma texasiensis I. Lea, 1838
Trapezoideus theca (W.H. Benson, 1862)
Radiatula theobaldi H.B. Preston, 1912
Pseudodon thomsoni P.M.A. Morelet, 1884
Aculamprotula tientsinensis (J.C.H. Crosse& E.O. Debeaux, 1863)