| details |
Early Pontian |
|
USSR(Ukrainian SSR) |
Dorofeev,P.I. On the discovery of a Pontian flora in the Ukraine |
1955 |
| details |
Miocene |
|
Canada(British Columbia) |
Hills,L.V. et al. Azolla primaeva and its phylogenetic significance. |
1967 |
| details |
Miocene |
|
USSR |
Friis,E.M. EM: Studies on Salviniaceae megaspores from the Middle Miocene Fasterholt Flora, Denmark. |
1977 |
| details |
Miocene |
|
Poland |
Friis,E.M. EM: Studies on Salviniaceae megaspores from the Middle Miocene Fasterholt Flora, Denmark. |
1977 |
| details |
Chattian |
Early Piacenzian |
Worldwide |
Kovach,W.L. et al. Worldwide stratigraphic occurrences of Mesozoic and Tertiary megaspores. |
1989 |
| details |
Miocene |
Middle Pliocene |
USSR(Ukrainian SSR) |
Batten,D.J. et al. Catalog of Mesozoic and Tertiary megaspores |
1990 |