Genus Operculum
- Species total:
- 3
- Age range:
- 414 - 392.33 MA (obsolete dating)
- IRMNG:
- find
| Name | From | To | Age range |
|---|---|---|---|
| Operculum type 1 | Ludlovian | Early Gedinnian |
|
| Operculum type 2 | Ludlovian | Early Gedinnian |
|
| Operculum type 3 | Ludlovian | Early Gedinnian |
|