| Name | From | To | Age range |
|---|---|---|---|
| Tetrad sp.B Manu.et al,1989 | Miocene | Miocene |
|
| Tetrad type A | Late Ordovician | Late Ordovician |
|
| Tetrad sp.2 | Emsian | Emsian |
|
| Tetrad sp.3 | Emsian | Emsian |
|
| Tetrad type 3 | Late Ordovician | Late Ordovician |
|
| Tetrad sp.A Manu.et al,1989 | Miocene | Miocene |
|
| Tetrad sp.1 | Emsian | Emsian |
|
| Tetrad sp. Stee.et al,2000 | Nd | Nd |
|
| Tetrad spore type 1,Saxe.& Rao,1996 | Early Miocene | Early Miocene |
|
| Tetrad type C Vavr.,1984 | Late Ordovician | Late Ordovician |
|
| Tetrad type A Vavr.,1984 | Ashgillian | Ashgillian |
|
| Tetrad type F | Late Ordovician | Late Ordovician |
|
| Tetrad sp. Vavr.,1984 | Late Ordovician | Late Ordovician |
|
| Tetrad type xxx | Miocene | Late Neogene |
|
| Tetrad type xxxi | Miocene | Late Neogene |
|
| Tetrad | Late Precambrian | Oligocene |
|
| Tetrad tetrahedral | Early Eocene | Middle Eocene |
|