Cosmarium holmiense var. constrictum Gutw. Dataset GBIF Backbone Taxonomy Rank VARIETY Classification kingdom Plantae phylum Charophyta class Zygnematophyceae order Zygnematales family Desmidiaceae genus Cosmarium species Cosmarium holmiense Name Homonyms Cosmarium holmiense f. constrictum Gutw., 1890 Cosmarium holmiense var. constrictum (Gutw.) Willi Krieger & Gerloff, 1965