| details |
Late Tremadocian |
Early Arenigian |
Italy(Sardinia) |
Pittau Demelia,P. Tremadocian (Early Ordovician) acritarchs of the Arburese Unit southwest Sardinia, (Italy). |
1985 |
| details |
Middle Cambrian |
|
USSR(Pre-Baltic) |
Pittau Demelia,P. Tremadocian (Early Ordovician) acritarchs of the Arburese Unit southwest Sardinia, (Italy). |
1985 |
| details |
Tremadocian |
|
Austria |
Reitz,E. et al. Biostratigraphic evidence of Lower Ordovician in the Innsbruck Quartzphyullite Group (Eastern Alps) |
1990 |
| details |
Middle Cambrian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Middle Cambrian |
|
USSR |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |
| 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 |