Identification key to the genus Acaudina
1. Presence of doughnut-shaped bodies….................................................................... 2
- Absence of doughnut-shaped bodies….................................................................... 5
2. Doughnut-shaped bodies spinose........................................................ … A. spinifera sp. nov.
- Doughnut-shaped bodies smooth…....................................................................... 3
3. Perforated plates either spinose or smooth….................................................... A. molpadioides
- Perforated plates always smooth…....................................................................... 4
4. Rod ossicles may have branched ends…........................................................... A. punctata
- Rod ossicles without branched ends….......................................................... A. leucoprocta
5. Ossicles absent…............................................................................ A. pellucida
- Ossicles present.................................................................................... …6
6. Rosette present in body wall….................................................................... A. rosettis
- Rosette absent in body wall…........................................................................... 7
7. Spinose subspherical ossicles present in body wall…................................................. A. demissa
- Spinose subspherical ossicles absent in body wall….......................................................... 8
8. Rod ossicles dominant in body wall; may be smooth or spinose........................................ … A. bacilla
- Spinose perforated plates dominant in body wall; rod ossicles always finely spinose…...................... A. suspecta