1. Species Undella attenuata Jörgensen, 1924
2. Species Undella biangulata Kofoid & Campbell, 1929
3. Species Undella californiensis Kofoid & Campbell, 1929
4. Species Undella clevei Jörgensen, 1924
5. Species Undella dilatata Kofoid & Campbell, 1929
6. Species Undella hadai Balech, 1962
7. Species Undella hyalina Daday 1887
8. Species Undella lachmanni Daday, 1887
9. Species Undella ostenfeldi Kofoid & Campbell, 1929
10. Species Undella pistillum Kofoid & Campbell, 1929
11. Species Undella turgida Kofoid & Campbell, 1929
12. Species Undella aculeata Jörgensen, 1924 accepted as Parundella aculeata (Jörgensen, 1924) (unaccepted > superseded combination)
13. Species Undella angustior Jörgensen, 1924 accepted as Undella claparedei var. angustior Jörgensen 1924 accepted as Proplectella angustior (Jörgensen, 1924) (never described in this combination)
14. Species Undella armata Brandt, 1906 accepted as Xystonellopsis armata Brandt, 1906
15. Species Undella azorica Cleve, 1899 accepted as Favella azorica (Cleve, 1899) Jörgensen, 1924
16. Species Undella campanula Schmidt, 1902 accepted as Favella campanula (Schmidt, 1902) Jörgensen, 1924 (unaccepted > superseded combination)
17. Species Undella caudata Jörgensen, 1924 accepted as Parundella caudata (Ostenfeld, 1899) Jörgensen, 1924 (unaccepted > superseded combination)
18. Species Undella claparedei (Entz) Daday, 1887 accepted as Proplectella claparedei (Entz, 1885) (unaccepted > superseded combination)
19. Species Undella collaria Brandt, 1906 accepted as Amplectella collaria (Brandt) Kofoid & Campbell, 1929
20. Species Undella filigera Laackmann, 1910 accepted as Albatrossiella filigera (Laackmann, 1910) Kofoid & Campbell, 1929
21. Species Undella globosa Brandt, 1906 accepted as Proplectella globosa (Brandt, 1906) emended Kofoid & Campbell, 1929 (not described as a species by brandt)
22. Species Undella heros Cleve, 1899 accepted as Xystonellopsis heros (Cleve) Kofoid & Campbell, 1929
23. Species Undella lachmanni Daday, 1887 accepted as Parundella lachmanni (Daday, 1887)
24. Species Undella lohmanni Jörgensen, 1924 accepted as Parundella lohmanni (Joergensen, 1924) Kofoid & Campbell, 1929 (unaccepted > superseded combination)
25. Species Undella marsupialis Brandt 1906 accepted as Undellopsis marsupialis (Brandt, 1906) Kofoid & Campbell, 1929 (unaccepted > superseded combination)
26. Species Undella messinensis Brandt, 1906 accepted as Parundella messinensis (Brandt, 1906) (unaccepted > superseded combination)
27. Species Undella monocollaria Laackmann, 1910 accepted as Amplectella monocollaria (Laackmann, 1910) Kofoid & Campbell, 1929 (unaccepted > superseded combination)
28. Species Undella paradoxa Cleve, 1899 accepted as Xystonellopsis paradoxa (Cleve, 1899) Jörgensen, 1924
29. Species Undella pellucida Jørgensen, 1900 accepted as Parundella pellucida (Jörgensen, 1900)
30. Species Undella pentagona (Jörgensen) Kofoid & Campbell 1929 accepted as Proplectella pentagona (Jörgensen) (unaccepted > superseded combination)
31. Species Undella perpusilla (Kofoid & Campbell, 1929) Balech 1975 accepted as Proplectella perpusilla Kofoid & Campbell, 1929 (unaccepted > superseded combination)
32. Species Undella subacuta Cleve, 1900 accepted as Proplectella subacuta (Cleve 1900) Kofoid & Campbell, 1929 (unaccepted > superseded combination)
33. Species Undella subcaudata Jörgensen, 1924 accepted as Proplectella subcaudata (Jörgensen, 1924) (not described as a species by Jörgensen)
34. Species Undella tenuirostris Brandt, 1906 accepted as Xystonellopsis tenuirostris Brandt, 1906 (unaccepted > superseded combination)
35. Species Undella tricollaria Laackmann, 1910 accepted as Amplectella tricollaria (Laackmann, 1910) Balech, 1975

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