Mendax theodosiae M. Jay & J. Drivas, 2002
Joculator thielei M. Jay & J. Drivas, 2002
Clathropsis thornleyana C.F. Laseron, 1956
Krachia tiara (T.A. de M. Monterosato,1874)
Joculator tieensis Cecalupo & Perugia, 2017
Joculator tomacula C.F. Laseron, 1956
Synthopsis tongoensis Cecalupo & Perugia, 2016
Belonimorphis touhoensis Cecalupo & Perugia, 2017
Joculator tribulationis (C. Hedley, 1909)
Ondulopsis tricolor A. Cecalupo & I. Perugia,2012
Cerithiopsis trigeminata (FOSSIL) G.P. Deshayes, 1864 †
Seila trilineata (R.A. Philippi, 1836)
Clathropsis tripilia (C.F. Laseron, 1951)
Socienna trisculpta (W.L. May, 1912)
Mendax trizonalis (N.H. Odhner, 1924)
Mendax trizonaloides B.A. Marshall, 1978
Marshallopsis troendlei A. Cecalupo & I. Perugia,2014
Cerithiopsis truncatum W.H. Dall, 1886
Horologica tsaoi C. Chen, C.F. Tseng& L.C. Lo, 2012
Joculator tsiriveloi A. Cecalupo & I. Perugia,2014
Clathropsis tuanainaii A. Cecalupo & I. Perugia,2014
Cerithiopsis tubercularis (G. Montagu, 1803)
Sundaya tuberculata A.W.B. Powell, 1927
Cerithiopsis tuberculoides P.P. Carpenter, 1857
Cerithiopsis tumida (P. Bartsch, 1907)
Synthopsis tumida A. Cecalupo & I. Perugia,2012
Ektonos turbonilloides (P. Dautzenberg& H. Fischer, 1896)
Synthopsis turgida A. Cecalupo & I. Perugia,2012
Tubercliopsis turgida A. Cecalupo & I. Perugia,2012
Marshallopsis turgida A. Cecalupo & I. Perugia,2012
Clathropsis turreta C.F. Laseron, 1956
Horologica turrigera (R.B. Watson, 1886)
Ondulopsis turrita A. Cecalupo & I. Perugia,2012
Synthopsis turritellata A. Cecalupo & I. Perugia,2012
Marshallopsis tutubaensis A. Cecalupo & I. Perugia,2013