Leptachatina resinula J.T. Gulick, 1856
Amastra reticulata (W. Newcomb, 1854)
Amastra reticulata dispersa A. Hyatt & H.A. Pilsbry,1911
Amastra reticulata orientalis A. Hyatt & H.A. Pilsbry,1911
Tropidoptera rex E.R. Sykes, 1904
Amastra ricei C.M. Cooke, 1917
Carelia rigida A. Hyatt
Amastra rubens (A.A. Gould, 1854)
Amastra rubida J.T. Gulick, 1873
Amastra rubristoma D.D. Baldwin, 1906
Amastra rugulosa (W.H. Pease, 1870)
Leptachatina saccula W.D. Hartman, 1888
Leptachatina sagittata H.A. Pilsbry & C.M. Cooke,1914
Leptachatina sandwicensis (L. Pfeiffer, 1846)
Laminella sanguinea (W. Newcomb, 1854)
Leptachatina saxatilis J.T. Gulick, 1856
Leptachatina sculpta L. Pfeiffer, 1856
Leptachatina scutilus (J.W. Mighels, 1845)
Leptachatina semicostata (L. Pfeiffer, 1855)
Amastra seminigra A. Hyatt & H.A. Pilsbry,1911
Amastra seminuda D.D. Baldwin, 1906
Leptachatina semipicta E.R. Sykes, 1896
Amastra senilis D.D. Baldwin, 1903
Amastra sericea L. Pfeiffer, 1859
Amastra similaris W.H. Pease, 1870
Leptachatina simplex W.H. Pease, 1869
Carelia sinclairi C.M.F. Ancey, 1892
Amastra sinistrorsa D.D. Baldwin, 1906
Leptachatina smithi E.R. Sykes, 1896
Amastra sola A. Hyatt & H.A. Pilsbry,1911
Amastra solida W.H. Pease
Leptachatina somniator H.A. Pilsbry & C.M. Cooke,1914
Amastra soror (W. Newcomb, 1854)
Planamastra spaldingi C.M. Cooke, 1933
Amastra sphaerica W.H. Pease, 1870