Staurastrum retusum var. boreale W. & G.S.West Dataset GBIF Backbone Taxonomy Rank VARIETY Classification kingdom Plantae phylum Charophyta class Zygnematophyceae order Zygnematales family Desmidiaceae genus Staurastrum species Staurastrum retusum Name Synonyms Cosmoastrum retusum var. boreale (West & G.S.West) Pal.-Mordv., 1982 Staurastrum thangaicum var. boreale (West & G.S.West) Brühl & Biswas, 1926 Homonyms Staurastrum retusum var. boreale W. & G.S.West