| original |
Early Arenigian |
Middle Arenigian |
Australia(Queensland) |
Playford,G. et al. Acritarch palynoflora of the Coolibah Formation (Lower Ordovician) Georgina Basin,Queensland. (In: Palynological and Palaeobotanical Studies in Honour of Basil E. Balme. P.A. Jell and G. Playford, editors) |
1988 |
| details |
Arenigian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Hunneberg |
|
Russia(St.Petersburg) |
Raevskaya,E.G. Early Arenig acritarchs from the Leetse Formation (St. Petersburg region, northwest Russia) and their palaeogeographic significance. |
1999 |