1. Subfamily Austrolithoideae A.S. Harvey & W.J. Woelkerling, 1995
   1. Genus Austrolithon A.S.Harvey & Woelkerling, 1995
   2. Genus Boreolithon A.S.Harvey & Woelkerling, 1995
   3. Genus Epulo R.A.Townsend & Huisman, 2004
2. Genus Boreolithothamnion P.W.Gabrielson, Maneveldt, Hughey & V.Peña, 2023
3. Genus Callilithophytum P.W.Gabrielson, W.H.Adey, G.P.Johnson & J.J.Hernandez-Kantun, 2015
4. Subfamily Choreonematoideae W.J. Woelkerling, 1987
   1. Tribe Choreonemateae
      1. Genus Choreonema F.Schmitz, 1889
5. Genus Lithothamnion Heydrich, 1897
6. Subfamily Melobesioideae Bizzozero, 1885
   1. Genus Crustaphytum L.-C.Liu & S.-M.Lin, 2018
   2. Genus Exilicrusta Y.M.Chamberlain, 1992
   3. Genus Mastophoropsis Woelkerling, 1978
   4. Genus Melobesia J.V.Lamouroux, 1812
   5. Genus Synarthrophyton R.A.Townsend, 1979
   6. Genus Agardhina Nardo, 1834 accepted as Phymatolithon Foslie, 1898
   7. Genus Antarcticophyllum (Me.Lemoine) M.L.Mendoza, 1976 accepted as Clathromorphum Foslie, 1898 (synonym)
   8. Genus Apora Gunnerus, 1768 accepted as Phymatolithon Foslie, 1898 (synonym)
   9. Genus Chaetolithon Foslie, 1898 accepted as Choreonema F.Schmitz, 1889 (synonym)
   10. Genus Eleutherospora Heydrich, 1900 accepted as Phymatolithon Foslie, 1898 (synonym)
   11. Genus Epilithon Heydrich, 1897 accepted as Melobesia J.V.Lamouroux, 1812 (synonym)
   12. Genus Hapalidium Kützing, 1843 accepted as Melobesia J.V.Lamouroux, 1812 (synonym)
   13. Genus Neopolyporolithon Adey & H.W.Johansen, 1972 accepted as Clathromorphum Foslie, 1898 (synonym)
   14. Genus Polyporolithon L.R.Mason, 1953 accepted as Mesophyllum Me.Lemoine, 1928 (synonym)
   15. Genus Squamolithon Heydrich, 1911 accepted as Lithothamnion Heydrich, 1897 (synonym)
   16. Genus Lithocystis Allman, 1848 (uncertain)
   17. Genus Sphaeranthera Heydrich, 1900 (uncertain > nomen dubium)
7. Genus Phymatolithon Foslie, 1898
8. Genus Roseolithon L.M.Coutinho & Barros-Barreto, 2021
9. Genus Thalassolithon Trentin, Moschin & Moro, 2023

 The webpage text is licensed under a Creative Commons Attribution 4.0 License