Belongs within: Cyanobacteriia. Phormidium is a genus of filamentous green algae with cells typically longer than wide, and with the end few cells of the filament tapering. Phormidium Kützing 1843C01 |–P. ambiguumL02 |–P. calcicocolaSG05 |–P. coriumW93 |–P. geysericola Copeland 1936 (n. d.)GH01 |–P. hendersoniiAG03 |–P. laminosumGP03 |–P. laysanenseAG03 |–P. mucicolaL02 |–P. retziiSA07 |–P. submembranaceumRA05 `–P.… Continue reading Phormidium


Belongs within: Terrabacteria.Contains: Aphralysiaceae, Entophysalidaceae, Myxococcoides, Cyanobacteriia. The Cyanobacteria are a clade of bacteria including the photosynthetic blue-green algae and their close relatives. The latter include the recently identified aquatic clades Sericytochromatia and Vampirovibrionia. The Sericytochromatia are little understood at present, being primarily represented in the literature by environmental sequences. Known representatives of the Vampirovibrionia… Continue reading Cyanobacteria


The Cyanobacteria, blue-green algae, is a distinctive group of photosynthetic bacteria possessing a dual photosystem allowing the use of H2O as a photoreductant leading to the release of oxygen. Chlorophyll a is primarily used as the reaction centre pigment, though chlorophyll b is also present in some species (Castenholz 2001). In the majority of Cyanobacteria,… Continue reading Cyanobacteriia


Belongs within: Cyanobacteriia.Contains: Rivulariaceae, Nostocaceae, Stigonematales. The Hormogoneae are a clade of filamentous blue-green algae including species in which one or more cells of trichomes differentiate into heterocysts. Hormogoneae [Microchaetaceae, Microchaetoideae, Nostocales] | i. s.: Petalonema alatumHB14, G64 | Hydrocoryne [incl. Hormothamnion]HB14 | StreptostemonHB14 | BorzinemaHB14 | SeguenzaeaHB14 | DactylothamnosHB14 | Archaeoellipsoides conjunctivus Zhang 1985TK06,… Continue reading Hormogoneae


Belongs within: Cyanobacteriia. The Pleurocapsales are blue-green algae reproducing via multiple fission of a parental cell to form small, spherical cells (baeocytes) that are released en masse via rupture of the parent’s fibrous outer wall (Castenholz 2001). Pleurocapsales |–Myxosarcina Printz 1921C01 [ChroococcidiaceaeA90] |–HyellaceaeE93 | |–Hyella gigasC01 | `–Eohyella campbelliae Zhang & Golubic 1987E93 |–PleurocapsaceaeE93 |… Continue reading Pleurocapsales


Belongs within: Hormogoneae.Contains: Tolypothrichaceae, Nostoc. The Nostocaceae are filamentous blue-green algae in which trichomes do not exhibit basal-apical polarity (Castenholz 2001). The Nostocaceae: tangled filaments Published 13 March 2012 The cyanobacteria, commonly referred to as the ‘blue-green algae’, were one of the first groups of bacteria to be recognised as distinct. As our knowledge of… Continue reading Nostocaceae


Belongs within: Nostocaceae. The Tolypothrichaceae are terrestrial or freshwater blue-green algae producing polarised filaments (Hauer et al. 2014). Characters (from Hauer et al. 2014): Polarised filaments with mainly basal, uniporous heterocytes. Single false branching very common, double branching occuring sporadically. Sheath thick or thin, but always present, sometimes coloured in yellow to yellow brown. Cells… Continue reading Tolypothrichaceae


Belongs within: Cyanobacteriia. Lyngbya is a genus of filamentous blue-green algae in which trichomes are surrounded by a more or less thick, persistent sheath (Castenholz 2001). Characters (from Castenholz 2001): Filamentous organisms producing a distinct, persistent, firm sheath. Sheath may be thin but can be seen with phase contrast optics, especially where extending beyond terminal… Continue reading Lyngbya


Belongs within: Hormogoneae. The Stigonematales are a group of blue-green algae in which the filamentous thalli exhibit cell reproduction by binary fission periodically or commonly in more than one plane, producing multiseriate and/or branched trichomes (Castenholz 2001). <==Stigonematales |–Chlorogloeopsis Mitra & Pandey 1966L02, C01 | `–C. fritschiiC01 `–StigonemataceaeA90 |–Langiella scourfieldi Croft & George 1959E93 |–Kidstoniella… Continue reading Stigonematales


Belongs within: Cyanobacteriia. Oscillatoria is a genus of blue-green algae growing as linear filaments. Characters (from Castenholz 2001): Filamentous organisms dividing exclusively by binary fission and in one plane. Cylindrical trichomes straight (occasionally except for terminal region); flexible or semirigid; over 4 µm in diameter; disc-like cells wider than long. Cross-walls generally visible by light… Continue reading Oscillatoria