1. Species Helix (Pella) actinotrichia Melvill & Ponsonby, 1892 accepted as Chilocystis actinotrichia (Melvill & Ponsonby, 1892) (basionym)
2. Species Helix (Pella) bathycoele Melvill & Ponsonby, 1892 accepted as Trachycystis bathycoele (Melvill & Ponsonby, 1892) (original combination)
3. Species Helix (Pella) burnupi Melvill & Ponsonby, 1892 accepted as Chalcocystis burnupi (Melvill & Ponsonby, 1892) (original combination)
4. Species Helix (Pella) congellana E. von Martens, 1860 (unaccepted > nomen nudum)
5. Species Helix (Pella) conisalea Melvill & Ponsonby, 1892 accepted as Chilocystis conisalea (Melvill & Ponsonby, 1892) (original combination)
6. Species Helix (Pella) crawfordi Melvill & Ponsonby, 1890 accepted as Sheldonia crawfordi (Melvill & Ponsonby, 1890) (original combination)
7. Species Helix (Pella) darnaudi L. Pfeiffer, 1857 accepted as Lejeania darnaudi (L. Pfeiffer, 1857)
8. Species Helix (Pella) epetrima Melvill & Ponsonby, 1892 accepted as Phaulocystis turmalis (Morelet, 1889) (unaccepted > junior subjective synonym)
9. Species Helix (Pella) erateina Melvill & Ponsonby, 1892 accepted as Lyrocystis prionacis (W. H. Benson, 1864) (unaccepted > junior subjective synonym)
10. Species Helix (Pella) liricostata Melvill & Ponsonby, 1891 accepted as Trachycystis liricostata (Melvill & Ponsonby, 1891) (unaccepted > superseded combination)
11. Species Helix (Pella) lygaea Melvill & Ponsonby, 1892 accepted as Chilocystis lygaea (Melvill & Ponsonby, 1892) (unaccepted > superseded combination)
12. Species Helix (Pella) minythodes Melvill & Ponsonby, 1892 accepted as Sheldonia crawfordi (Melvill & Ponsonby, 1890) (unaccepted > junior subjective synonym)
13. Species Helix (Pella) namaquana E. von Martens, 1889 accepted as Xerocystis capensis var. namaquana (E. von Martens, 1889) accepted as Xerocystis capensis (L. Pfeiffer, 1841)
14. Species Helix (Pella) rhysodes Melvill & Ponsonby, 1892 accepted as Lyrocystis perplicata (W. H. Benson, 1851) (synonym)
15. Species Helix (Pella) strobilodes Melvill & Ponsonby, 1893 accepted as Chilocystis trichosteiroma (Melvill & Ponsonby, 1892) (unaccepted > junior subjective synonym)
16. Species Helix (Pella) trichosteiroma Melvill & Ponsonby, 1892 accepted as Chilocystis trichosteiroma (Melvill & Ponsonby, 1892) (unaccepted > superseded combination)
17. Species Helix (Pella) tuguriolum Melvill & Ponsonby, 1892 accepted as Trachycystis (Trachycystis) tollini (W. H. Benson, 1856) represented as Trachycystis tollini (W. H. Benson, 1856) (unaccepted > junior subjective synonym)
18. Species Helix (Pella) whytei E. A. Smith, 1894 accepted as Zingis whytei (E. A. Smith, 1894) (basionym)

 The webpage text is licensed under a Creative Commons Attribution 4.0 License