calothrix calothrix calothrix is a genus of cyanobacteria. they are generally found in freshwater. bright-field microscopy image of epiphytic cyanobacterial symbiont calothrix rhizosoleniae sc01 9 (indicated by arrows) attached to a host diatom chaetoceros sp. (c). scale bar, 50 μm. calothrix a 1921 drawing of calothrix scientific classification domain: bacteria phylum: cyanobacteria class: cyanophyceae order: nostocales family: rivulariaceae genus: calothrixbornet & flahault 1886 species calothrix adscendens calothrix atricha calothrix braunii calothrix breviarticulata calothrix caespitora calothrix confervicola calothrix crustacea calothrix donnelli calothrix elenkinii calothrix epiphytica calothrix fusca calothrix juliana calothrix parasitica calothrix parietina calothrix pilosa calothrix pulvinata calothrix scopulorum calothrix scytonemicola calothrix simulans calothrix solitaria calothrix stagnalis calothrix stellaris calothrix thermalis calothrix 336/3