1. Species Ancylus (Ferrissia) baconi Bourguignat, 1853 accepted as Pettancylus baconi (Bourguignat, 1854) (unaccepted combination)
2. Species Ancylus (Ferrissia) bermudensis Vanatta, 1911 accepted as Ferrissia bermudensis (Vanatta, 1911)
3. Species Ancylus (Ferrissia) borealis E. S. Morse, 1864 accepted as Ferrissia rivularis (Say, 1817) (junior synonym)
4. Species Ancylus (Ferrissia) burnupi B. Walker, 1912 accepted as Pettancylus burnupi (B. Walker, 1912) (original combination)
5. Species Ancylus (Ferrissia) connollyi B. Walker, 1912 accepted as Pettancylus connollyi (B. Walker, 1912) (original combination)
6. Species Ancylus (Ferrissia) elatior J. G. Anthony, 1855 accepted as Rhodacmea elatior (J. G. Anthony, 1855) (unaccepted combination)
7. Species Ancylus (Ferrissia) equeefensis B. Walker, 1912 accepted as Pettancylus burnupi (B. Walker, 1912) (subjective synonym)
8. Species Ancylus (Ferrissia) filosus Conrad, 1834 accepted as Rhodacmea filosa (Conrad, 1834) (unaccepted combination)
9. Species Ancylus (Ferrissia) fontinalis B. Walker, 1912 accepted as Ferrissia fontinalis (B. Walker, 1912) accepted as Pettancylus fontinalis (B. Walker, 1912) (original combination)
10. Species Ancylus (Ferrissia) gordonensis Melvill & Ponsonby, 1903 accepted as Burnupia gordonensis (Melvill & Ponsonby, 1903) (unaccepted > superseded combination)
11. Species Ancylus (Ferrissia) haldemani Bourguignat, 1853 accepted as Ferrissia rivularis (Say, 1817) (junior synonym)
12. Species Ancylus (Ferrissia) hendersoni B. Walker, 1908 accepted as Ferrissia fragilis (Tryon, 1863) accepted as Ferrissia californica (Rowell, 1863) (unaccepted > junior subjective synonym)
13. Species Ancylus (Ferrissia) hinkleyi B. Walker, 1908 accepted as Rhodacmea hinkleyi (B. Walker, 1908)
14. Species Ancylus (Ferrissia) novangliae B. Walker, 1908 accepted as Ferrissia fragilis (Tryon, 1863) accepted as Ferrissia californica (Rowell, 1863)
15. Species Ancylus (Ferrissia) ovalis E. S. Morse, 1864 accepted as Ferrissia rivularis (Say, 1817) (junior synonym)
16. Species Ancylus (Ferrissia) parallelus Haldeman, 1841 accepted as Ferrissia rivularis (Say, 1817) (junior synonym)
17. Species Ancylus (Ferrissia) pumilus Sterki, 1900 accepted as Ferrissia fragilis (Tryon, 1863) accepted as Ferrissia californica (Rowell, 1863) (junior synonym)
18. Species Ancylus (Ferrissia) rivularis Say, 1817 accepted as Ferrissia rivularis (Say, 1817) (unaccepted combination)
19. Species Ancylus (Ferrissia) shimeki Pilsbry, 1890 accepted as Ferrissia fragilis (Tryon, 1863) accepted as Ferrissia californica (Rowell, 1863) (junior synonym)
20. Species Ancylus (Ferrissia) stenochorias Melvill & Ponsonby, 1903 accepted as Burnupia stenochorias (Melvill & Ponsonby, 1903) (unaccepted > superseded combination)
21. Species Ancylus (Ferrissia) verruca W. H. Benson, 1855 accepted as Pettancylus verruca (W. H. Benson, 1855) (unaccepted combination)
22. Species Ancylus (Ferrissia) victoriensis B. Walker, 1912 accepted as Pettancylus victoriensis (B. Walker, 1912) (original combination)
23. Species Ancylus (Ferrissia) viola Annandale & Prashad, 1921 accepted as Pettancylus viola (Annandale & Prashad, 1921) (original combination)
24. Species Ancylus (Ferrissia) zambesiensis B. Walker, 1912 accepted as Pettancylus zambesiensis (B. Walker, 1912) (original combination)

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