Clithon teres T.C. Eichhorst, 2016
Nerita tessellata J.F. Gmelin, 1791 South Australia18 mm
Septaria tessellata (J.B.P.A. Lamarck, 1816) Sri Lanka21 mm
Neritoma tethys (FOSSIL) Morris 1949 †
Nerita textilis J.F. Gmelin, 1791 South Africa, Natal27,8 mm
Neritina tiassalensis E.E. Binder, 1955 Ivory coast, Abidjan
Theodoxus timisensis (FOSSIL) E. Jekelius, 1944 †
Theodoxus tingitana (P.M. Pallary, 1936) Morocco, cap Cantin6 mm
Neritina tjidamarensis (FOSSIL) Martin, 1879 † Indonesia, Junghuhn
Theodoxus tortuosus (FOSSIL) E. Jekelius, 1944 †
Smaragdia tragena (T. Iredale, 1936) Réunion
Theodoxus transversalis (L. Pfeiffer, 1828) Hungary, Raba river, Rabahidveg
Theliostyla triangulata (FOSSIL) W.M. Gabb, 1869 †
Nerita tricarinata (FOSSIL) J.B.P.A. Lamarck, 1804 † France, Brittany
Nerita tricarinata pentastoma (FOSSIL) G.P. Deshayes, 1864 † France, Paris Basin
Theodoxus trifasciatus (FOSSIL) (J.P.S. Grateloup,1839 †)
Theodoxus trilophosensis (FOSSIL) Rust, 1997 †
Nerita tristis H.A. Pilsbry, 1901 Japan, Oshima Island
Clithon tritonensis (E.J. Le Guillou, 1841) Papua New Guinea8 mm
Theodoxus tropidophorus (FOSSIL) (Š. Brusina, 1884 †)
Cuisenerita tuberosa (FOSSIL) Symonds & J.M. Pacaud,2010 † France, Oise12,5 mm
Theodoxus turbinatus (FOSSIL) (A. Fuchs, 1870 †)
Theodoxus turislavicus (FOSSIL) E. Jekelius, 1944 †
Neritina turrita (J.F. Gmelin, 1791) Philippines, Samar Island23 mm
Neritina turrita cumingiana C.A. Récluz Philippines, Samar Island30 mm
Vittina turtoni (C.A. Récluz, 1843) Fiji Islands17 mm
Nerita umlaasiana (C.F.F. von Krauss, 1848) South Africa, Natal15,5 mm
Nerita undata C. Linnaeus, 1758 Philippines, Negros Island37 mm
Nerita undata spengleriana C.A. Récluz, 1844 Indonesia25 mm
Nerita undulata J.F. Gmelin, 1791 Singapore18 mm
Theodoxus unguiculatus (FOSSIL) (Seninski, 1905 †)
Neritina unidenta (FOSSIL) T.H. Aldrich, 1911 † Alabama
Neritina unidentata C.A. Récluz, 1850 Society Islands
Neritina usnea (P.F. Röding, 1798) Florida16,1 mm
Neritina usnea reclivata T. Say, 1822 Florida, Miami County17 mm