| original |
Early Gothlandian |
|
USSR(Baltic) |
Fensome,R.A. et al. Acritarchs and Fossil Prasinophytes: An index to genera, species and infraspecific taxa. |
1990 |
| details |
Late Gothlandian |
|
USSR(Lithuanian SSR) |
Sarjeant,W.A.S. et al. The Micrhystridium and Veryhachium Complexes (Acritarcha: Acanthomorphitae and Polygonomorphitae): A taxonomic reconsideration. |
1994 |
| details |
Late Silurian |
|
USSR(Lithuanian SSR) |
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 |