| Name | From | To | Age range |
|---|---|---|---|
| Alnus pre-japonica | Late Paleocene | Early Pliocene |
|
| Alnus pre-cordata | Late Paleocene | Early Pliocene |
|
| Alnus praerhombifolia | Oligocene | Oligocene |
|
| Alnus polleminensis | Quaternary | Quaternary |
|
| Alnus pigmaeus | Maastrichtian | Maastrichtian |
|
| Alnus percuriosa | Paleogene | Neogene |
|
| Alnus pentaporina | Maastrichtian | Paleocene |
|
| Alnus pentagona | Late Eocene | Late Eocene |
|
| Alnus parva | Paleogene | Neogene |
|
| Alnus paleocordata | Late Miocene | Late Miocene |
|
| Alnus opulenta | Paleogene | Neogene |
|
| Alnus nostartum | Late Neogene | Late Neogene |
|
| Alnus nepalensis | Late Eocene | Late Pliocene |
|
| Alnus minuta | Late Campanian | Sarmatian |
|
| Alnus menzelii | Paleogene | Neogene |
|
| Alnus maritima | Paleogene | Neogene |
|
| Alnus kireevskiana | Miocene | Miocene |
|