| original |
Middle Cambrian |
|
Spain |
Fombella,M.A. Acritachs of the lower middle Cambrian from the Province of Leon, Spain. |
1977 |
| details |
Nd |
|
Nd |
Cramer,F.H. et al. Lower Paleozoic acritarchs. |
1979 |
| details |
Middle Cambrian |
|
Canada(Newfoundland) |
Martin,F. et al. Middle and Upper Cambrian and Lower Ordovician acritarchs from Random Island, Eastern Newfoundland. |
1981 |
| details |
Nd |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Nd |
|
Nd |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |