| details |
Middle Ordovician |
Late Ordovician |
New York |
Jacobson,S.R. Middle and Upper Ordovician acritarchs, Eastern Midcontinent, USA. |
1977 |
| details |
Middle Ordovician |
Late Ordovician |
Ohio |
Jacobson,S.R. Middle and Upper Ordovician acritarchs, Eastern Midcontinent, USA. |
1977 |
| details |
Caradocian |
|
Ohio |
Jacobson,S.R. Acritarch biostratigraphy of Middle and Late Ordovician Carbonate rocks of the Trenton Group, New York, and equivalent strata in the Cincinnati region. |
1977 |
| details |
Tremadocian |
|
Spain |
Fombella Blanco,M.A. Chitinozoans from the Oville Formation, Tremadocian of the Province of Leon. |
1982 |
| details |
Tremadocian |
|
Spain |
Fombella Blanco,M.A. Chitinizoa of the Tremadocian Oville Formation, Leon Province. |
1983 |
| details |
Nd |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Arenigian |
Ashgillian |
Saudi Arabia |
Fauconnier,D. Palynological study of Formations of Tertiary Upper Cretaceous, Devonian, Silurian, and Ordovician intersected in 11 boreholes in Northwestern of Royaume, Saudi Arabia (RS.1717) |
1984 |
| details |
Late Tremadocian |
|
China(Yunnan) |
Fang,X. Ordovician micropaleoplants in Kunming-Luguan Region, Yunnan Province and their stratigraphical significance. |
1985 |
| details |
Nd |
|
Nd |
Evitt,W.R. A discussion and proposals concerning fossil dinoflagellates, Hystrichospheres, and acritarchs. II. |
1963 |
| details |
Cambrian |
|
Nd |
Eisenack,A. Hystricosphaeres |
1963 |
| details |
Tremadocian |
Arenigian |
Wales |
Downie,C. et al. Changes in the acritarch assemblages at the Tremadoc boundaries in the United Kingdom. |
1979 |
| details |
Late Cambrian |
Early Ordovician |
Nd |
Downie,C. Observations on the nature of the acritarchs |
1973 |
| details |
Vendian |
Cambrian |
W.Germany(Niedersachsen) |
Deflandre,G. et al. Nomenclature and systematics of Hystrichospheres (Sens.Lat.) observations and recitifications. |
1961 |
| details |
Vendian |
Cambrian |
W.Germany(Niedersachsen) |
Deflandre,G. et al. Nomenclature and systematics of the Hystrichospheres (Sens.Lat.), observations and rectifications. |
1962 |
| details |
Nd |
|
Nd |
Deflandre,G. et al. Notes on the acritarchs. |
1963 |
| details |
Ordovician |
|
Brazil(Amazonas) |
de Quadros,L.P. et al. Ordovician acritarchae in the Alto Amazonas Sub-Basin, Brazil. |
1986 |
| details |
Arenigian |
Llanvirnian |
Brazil(Amazonas) |
de Quadros,L.P. Occurence of Ordovician microfossils (Acritarchae) in the Alto Amazon Sub Basin, Brazil. |
1986 |