| details |
Early Tremadocian |
|
Belgium |
Eisenack,A. et al. Catalog of fossil dinoflagellates, hystrichospheres and related microfossils. Acritarchs. |
1973 |
| details |
Tremadocian |
|
Nd |
Diez,M.D.C.R. et al. Range chart of selected Lower Paleozoic acritarch Taxa. |
1974 |
| details |
Tremadocian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Late Arenigian |
Ashgillian |
USSR(Estonian SSR) |
Uutela,A. et al. Ordovician acritarchs from the Rapla borehole, Estonia |
1991 |
| details |
Early Caradocian |
|
Sweden |
Wallin,A. et al. Biostratigraphical investigation of Middle Ordovician acritarch the post-impact sequence in the Tvaren-2 core, Sweden. |
1996 |