Dodatak:Popis zelenih alga, U
Ud
uredi- Udotea J.V.Lamouroux, 1812
- Udoteaceae
- Udoteaceae J. Agardh, 1887
Ul
uredi- Ulochloris Pascher
- Ulothrix Kützing, 1833
- Ulotrichaceae Kützing, 1843
- Ulotrichales
- Ulotrichella Iyengar, 1975
- Ulotrichopsis L.Wichmann, 1937
- Ulotrichopsis Wichmann, 1937
- Ulva Linnaeus, 1753
- Ulvaceae J.V. Lamouroux ex Dumortier, 1822
- Ulvales
- Ulvales incertae sedis
- Ulvaria Ruprecht, 1850
- Ulvella P.L.Crouan & H.M.Crouan, 1859
- Ulvellaceae Schmidle, 1899
- Ulvophyceae
- Ulvophyceae incertae sedis
Um
uredi- Umbella V.P.Maslov
- Umbraulva E.H.Bae & I.K.Lee, 2001
Un
uredi- Unjaeella Korde
Ur
uredi- Uragiella J.Pia
- Uralella K.B.Korde
- Uraloporella K.B.Korde
- Urnella Playfair, 1918
- Uronema Lagerheim, 1887
- Urospora Areschoug, 1866
Ut
uredi- Uteria J.-J.H.Michelin
- Uterioides G.Segonzac
Uv
uredi- Uva stellata Korshikov
Plantae → Chlorophyta → Chlorophyceae → Chlamydomonadales → Spondylomoraceae
- Uvella Bory de Saint-Vincent, 1824
- Uva suspecta V. P. Maslov
Plantae → Chlorophyta → Bryopsidophyceae → Bryopsidales → Codiaceae