Name(s) in cluster
| Ptychodus polygyrus Agassiz 1843 | urn:lsid:organismnames.com:name:158903 |
| Ptychodus polygyrus Ag. | urn:lsid:organismnames.com:name:3949176 |
| Ptychodus polygyrus Agassiz 1839 | urn:lsid:organismnames.com:name:4429663 |
| Ptychodus polygyrus | urn:lsid:organismnames.com:name:732267 |
| Ptychodus polygyrus Agassiz 1835 | urn:lsid:organismnames.com:name:4943457 |
...