| details |
Late Arenigian |
Early Llanvirnian |
Morocco |
Cramer,F.H. et al. Early Ordovician acritarchs from the Tadla Basin of Morocco. |
1974 |
| details |
Ludlovian |
Early Gedinnian |
Spain |
Cramer,F.H. et al. Early Ordovician acritarchs from the Tadla Basin of Morocco. |
1974 |
| details |
Tremadocian |
Late Arenigian |
Morocco |
Swain,F.M. Notes on Paleozoic acritarchs from the Atlantic Margins. (In: Stratigraphic Micropaleontology of Atlantic Basin and Borderlands. F.M.Swain, editor) |
1977 |
| details |
Ludlovian |
Early Gedinnian |
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |