| details |
Early Ordovician |
Middle Ordovician |
USSR(Estonian SSR) |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |
| details |
Late Arenigian |
Early Llanvirnian |
Sweden |
Ribecai,C. et al. Arenigian acritarch from Horns Udde (Oland, Sweden). A preliminary report. |
1995 |
| details |
Nd |
|
Nd |
Sarjeant,W.A.S. et al. The acritarch genus Polygonium, Vavrdova emend. Sarjeant and Stancliffe 1994: a reassessment of its constituent species. (In: Stratigraphie du Mesozoique et du Cenozoique. M.Streel, editor) |
1996 |
| details |
Late Arenigian |
Early Llanvirnian |
Sweden |
Tongiorgi,M. et al. Differentiation and spread of the Baltic Acritarch Province (Arenig-Llanvirn). |
1999 |
| details |
Lasnamagi |
|
Lithuania |
Pa?keviciene,L. Acritarchs of the Lasnam¤gi and Uhaku Regional Stages in the South-eastern Baltic region. |
2002 |