Phylum Cyanobacteria Garcia-Pichel et al. (2020) see Phylum Cyanobacteriota Oren et al. 2022
   Class Cyanophyceae Hauck (1885) see Class Chroococcophyceae Hollerbach et al. 1953
     Order Nostocales Borzì (1914) see Order Nostocales corrig. Borzì 1914
       Family Hapalosiphonaceae Elenkin (1917), nom. cons. see Family Hapalosiphonaceae Elenkin 1917
         01 ?Genus Albrightia Copel. (1936) see Genus Albrightia Copeland 1936
         02 ?Genus Baradlaia P. Palik (1960) see Genus Baradlaia Palik 1960
         03 ?Genus Brachytrichiopsis Jao (1944) see Genus Brachytrichiopsis Jao 1944
         04 Genus Chlorogloeopsis A.K. Mitra & D.C. Pandey (1967) see Genus Chlorogloeopsis Mitra and Pandey 1967
         05 ?Genus Chondrogloea W. Schmidle (1901) see Genus Chondrogloea Schmidle 1901
         06 ?Genus Dictyophoron Komárek, Komárková, Ventura, Kozlíková-Zapomělová & Rejmánková (2017)
         07 Genus Fischerella (Bornet & Flahault) Gomont (1895) see Genus Fischerella (Bornet and Flahault 1886) Gomont 1895
         08 ?Genus Fischerellopsis Fritsch (1932) see Genus Fischerella (Bornet and Flahault 1886) Gomont 1895
         09 ?Genus Handeliella Skuja (1937) see Genus Handeliella Skuja 1937
         10 ?Genus Hapalosiphon C. Nägeli ex Bornet & Flahault (1886) see Genus Hapalosiphon Nägeli ex Bornet and Flahault 1886
         11 ?Genus Hyphomorpha A. Borzì (1916) see Genus Hyphomorpha Borzì 1916
         12 ?Genus Leptopogon Borzì (1907) see Genus Leptopogon Borzì 1907
         13 ?Genus Letestuinema Frémy (1930) see Genus Letestuinema Frémy 1930
         14 ?Genus Loefgrenia Gomont (1896) see Genus Loefgrenia Gomont 1896
         15 ?Genus Loriella A. Borzì (1892) see Genus Loriella Borzì 1892
         16 Genus Mastigocladus F.J. Cohn ex O. Kirchner (1898) see Genus Mastigocladus Cohn ex Kirchner 1898
         17 ?Genus Mastigocoleopsis Geitler (1925) see Genus Mastigocoleopsis Geitler 1925
         18 ?Genus Matteia A. Borzì (1907) see Genus Matteia Borzì 1907
         19 Genus Neowestiellopsis Kabirnataj, Nematzadeh, Talebi, Tabatabaei & Singh (2018) see Genus Neowestiellopsis Kabirnataj et al. 2018
         20 Genus Nostochopsis Wood ex Bornet & Flahault (1886) see Genus Nostochopsis Wood ex Bornet and Flahault 1886
         21 Genus Pelatocladus Johansen & Vaccarino (2016) see Genus Pelatocladus Johansen and Vaccarino 2016
         22 Genus Reptodigitus D.A. Casamatta, C.D. Villanueva, H.S. Stocks, M. Vaccarino & J.R. Johansen (2020) see Genus Reptodigitus Casamatta et al. 2020
         23 ?Genus Schmidleinema G.De Toni (1936) see Genus Schmidleinema De Toni 1936
         24 ?Genus Spelaeopogon Borzì (1907) see Genus Spelaeopogon Borzì 1907
         25 ?Genus Thalpophila Borzì (1907) see Genus Thalpophila Borzì 1907
         26 ?Genus Westiella Borzì (1907) see Genus Westiella Borzì 1907
         27 Genus Westiellopsis Janet (1941) see Genus Westiellopsis Janet 1941