Mangelia tranquilla K.H. Barnard, 1958
Heterocithara transenna C. Hedley, 1922
Pseudorhaphitoma transitans C. Hedley, 1922
Leiocithara translucens (K.H. Barnard, 1958)
Curtitoma trevelliana (W. Turton, 1834)
Heterocithara tribulationis (C. Hedley, 1909)
Cryoturris trilineata (C.B. Adams, 1845)
Tenaturris trilineata (C.B. Adams, 1845)
Tenaturris trilineata maculata G.W. Nowell-Usticke, 1969
Oenopota triphera (A.N. Golikov& O.A. Scarlato, 1967)
Mangelia tritaeniata J.C. Melvill, 1917
Eucithara triticea (L.C. Kiener, 1840)
Eucithara trivittata (A. Adams & L.A. Reeve,1850)
Mangelia trizonata E.A. Smith, 1882
Benthomangelia trophonoidea (M.M. Schepman, 1913)
Pseudorhaphitoma tropica (K.H.J. Thiele, 1925)
Marita tumida C.F. Laseron, 1954
Obesotoma tumida (H.J. Posselt, 1898)
Bela turcica K.H.J. Thiele, 1925
Bela turgida (L.A. Reeve, 1844)
Eucithara turricula (L.A. Reeve, 1846)
Propebela turricula (G. Montagu, 1803)
Pyrgocythara turrispiralata (FOSSIL) Scarponi & al., 2016 †
Brachycythara turrita W.C. Mansfield, 1930
Eucithara typhonota (J.C. Melvill & R. Standen,1901)
Eucithara typica (E.A. Smith, 1884)
Eucithara ubuhle R.N. Kilburn, 1992
Obesotoma uchidai T. Habe, 1958
Oenopotella ultraabyssalis A.V. Sysoev, 1988
Pseudorhaphitoma uncicostata R.N. Kilburn & H. Dekker,2008
Oenopota undata (T.A. Verkrüzen, 1878)
Eucithara unifasciata (G.P. Deshayes, 1834)
Mangelia unifasciata (G.P. Deshayes, 1835)
Mangelia unifasciata derelicta L.A. Reeve, 1846
Mangelia unifasciata galli (Ant. Bivona-Bernardi,1838)