| details |
Early Gothlandian |
|
Belgium |
Martin,F. The acritarchs from the Belgian Ordovician and Silurian. Determination and stratigraphic value. |
1968 |
| details |
Ludlovian |
|
Spain |
Cramer,F.H. Distribution of selected Silurian acritarchs an account of the palynostratigraphy and paleogeography of selected Silurian acritarch Taxa |
1970 |
| details |
Late Wenlockian |
Early Pridolian |
Nd |
Cramer,F.H. Distribution of selected Silurian acritarchs an account of the palynostratigraphy and paleogeography of selected Silurian acritarch Taxa |
1970 |
| details |
Early Llandoverian |
|
Belgium |
Martin,F. The Upper Ordovician and Lower Silurian at Deerlijk (Belgium) |
1973 |
| details |
Early Eltonian |
Downtonian |
England(Shropshire) |
Lister,T.R. et al. The stratigraphic distribution of the acritarchs in the Ludlow succession at Ludlow. |
1974 |
| details |
Early Gedinnian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |