| original |
Middle Ordovician |
Late Ordovician |
Oklahoma |
Tappan,H. et al. Surface sculpture of the wall in Lower Paleozoic acritarchs. |
1971 |
| 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 |
Nd |
|
Nd |
Loeblich,A.R.,Jr. et al. Some Middle and Late Ordovician microphytoplankton from Central North America. |
1978 |
| details |
Middle Ordovician |
Late Ordovician |
Ohio |
Jacobson,S.R. Acritarchs as paleoenvironmental indicators in Middle and Upper Ordovician rocks from Kentucky, Ohio and New York. |
1979 |
| details |
Middle Ordovician |
Late Ordovician |
New York |
Jacobson,S.R. Acritarchs as paleoenvironmental indicators in Middle and Upper Ordovician rocks from Kentucky, Ohio and New York. |
1979 |
| details |
Nd |
|
Nd |
Cramer,F.H. et al. Lower Paleozoic acritarchs. |
1979 |
| details |
Late Ordovician |
|
Indiana |
Miller,M.A. et al. Upper Ordovician (Lower Richmondian) acritarchs and chitinozoans from southeastern Indiana, USA. |
1981 |
| details |
Nd |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Early Ordovician |
|
China(Hupei) |
Yin,L.-M. New forms of acritarch from Early Ordovician sediments in Yichang, Hubei, China. |
1994 |
| details |
Nd |
|
Nd |
Colbath,G.K. et al. Review of biological affinities of Paleozoic acid-resistant, organic walled eukaryotic algal microfossils, (including acritarchs). |
1995 |
| details |
Ordovician |
|
Nd |
Servais,T. An annotated bibliographical review of Ordovician acritarchs |
1997 |