| details |
Late Ordovician |
Early Silurian |
Nd |
Taylor,W.A. Evolutionary hypothesis of Cryptospore producing plants based on wall ultrastructure. |
2001 |
| details |
Ashgillian |
|
Belgium |
Steemans,P. Ordovician cryptospores from the Oostduinkerke Borehole, Brabant Massif, Belgium. |
2001 |
| details |
Caradocian |
Early Gedinnian |
Nd |
Richardson,J.B. Paleozoic spores and pollen: Lower and Middle Palaeozoic record of terrestrial palynomorphs. (Principles and Applications. Applications. J.Jansonius and D.C.McGregor, editors.) |
1996 |
| original |
Rhuddanian |
|
Wales(Dyfed) |
Burgess,N.D. Silurian Cryptospores and miospores from the type Llandovery area, southwest Wales. |
1991 |
| details |
Hirnantian |
Aeronian |
Wales(Dyfed) |
Burgess,N.D. Silurian Cryptospores and miospores from the type Llandovery area, southwest Wales. |
1991 |