| Synonym | Author | CoL Status | Valid | Synonymy | Combination |
|---|---|---|---|---|---|
| ! Hydrasterias improvisa | (Ludwig, 1905) | synonym | No | senior synonym |
new combination |
| Hydrasterias improvisus | (Ludwig, 1905) | accepted name | Yes | senior synonym |
new combination |
| Pedicellaster improvisus | Ludwig, 1905 | synonym | No | senior synonym |
original combination |