Genus Polonosphaeridium
- Species total:
- 3
- Age range:
- 500 - 395 MA (obsolete dating)
- IRMNG:
- find
| Name | From | To | Age range |
|---|---|---|---|
| Polonosphaeridium | Ordovician | Silurian |
|
| Polonosphaeridium francinae | Middle Ordovician | Middle Ordovician |
|
| Polonosphaeridium ordovicum | Middle Ordovician | Middle Ordovician |
|