Subject
- Specific Epithet: fissa 2
- Specific Epithet: flaccida 3
- Specific Epithet: flagellare 23
- Specific Epithet: flavicans 1
- Specific Epithet: flexicaule 2
- Specific Epithet: flexuosa 8
- Specific Epithet: flexuosus 1
- Specific Epithet: fluitans 6
- Specific Epithet: fluviatile 5
- Specific Epithet: foliosum 13
- Specific Epithet: fontana 25
- Specific Epithet: fontanus 4
- Specific Epithet: fossombronioides 1
- Specific Epithet: foveolata 4
- Specific Epithet: fragilis 2
- Specific Epithet: fragrans 1
- Specific Epithet: fulvum 18
- Specific Epithet: furcata 1
- Specific Epithet: fuscescens 3
- Specific Epithet: fuscum 4