| original |
Llandoverian |
|
USSR(Tuvinskaya A.O.) |
Sheshegova,L.I. Phytoplankton of the Silurian from the Tuva, (the section of the "Elegest"). |
1975 |
| details |
Llandoverian |
|
Nd |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Late Ordovician |
|
USSR(Siberia) |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |
| details |
Early Silurian |
|
USSR(Russia) |
Stancliffe,R.P.W. et al. The acritarch genus Veryhachium Deunff,1954, emend., Sarjeant and Stancliffe,1994: A taxonomic restudy and a reassessment of its constituent species. |
1994 |