Cyclothyrella klietmanni (FOSSIL) (T.A. Neubauer in T.A. Neubauer& al., 2011 †)
Heideella knidirii M. Ghamizi, 1998
Caspia knipowitchi M. Makarov, 1938
Clathrocaspia knipowitschii Makarov, 1938
Hydrobia knysnaensis (C.F.F. von Krauss, 1848)
Akiyoshia kobayashii J.T. Kuroda & T. Habe,1958
Graecoanatolica kocapinarica P. Radoman, 1973
Goniochilus kochii (FOSSIL) (A. Fuchs, 1870 †)
Caspia kojumdgievae (FOSSIL) Roshka, 1973 †
Pyrgula kolesnikoviana B.M. Logvinenko& Y.I. Starobogatov, 1966
Bythiospeum kolevi D.G. Georgiev, 2013
Pyrgulopsis kolobensis D.W. Taylor, 1987
Belgrandiella komenskyi V. Hüdec, 1972
Pyrgula konstantinovici (FOSSIL) P.S. Pavlovic, 1932 †
Belgrandiella koprivnensis P. Radoman, 1975
Fluviopupa korobebe S. Zielske & M. Haase,2014
Turricaspia korobkovi (FOSSIL) Roshka, 1973 †
Terranigra kosovica P. Radoman, 1978
Lanzaia kotlusae J. Bole, 1992
Pseudamnicola kotschyi (G.R. von Frauenfeld,1863)
Pyrgula kowalewskii (S. Clessin& W. Dybowski in W. Dybowski, 1888)
Caspia krambergeri (FOSSIL) (Lörenthey, 1902 †)
Bythiospeum kraussi (C.D. Weinland, 1883)
Belgrandiella kreisslorum P.L. Reischütz, 1997
Pyrgula krejcii (FOSSIL) W.A. Wenz in Krejci-Graf& W.A. Wenz, 1932 †
Hadziella krkae J. Bole, 1992
Pseudamnicola krumensis P. Glöer, J. Grego, Z. Eröss& Z. Fehér, 2015
Belgrandiella krupensis P. Radoman, 1973
Devetakia krushunica D.G. Georgiev & P. Glöer,2011
Beddomeia krybetes W.F. Ponder & K.B. Clark,1993
Hydrobia kubanica (FOSSIL) Zhizhchenko, 1936 †
Belgrandiella kuesteri (H.D. Boeters, 1970)
Palacanthilhiopsis kuiperi H. Girardi, 2009
Prososthenia kupensis (FOSSIL) Š. Brusina, 1902 †
Belgrandiella kusceri (A.J. Wagner, 1914)