Eunotia arcus var. bidens Grunow Dataset GBIF Backbone Taxonomy Rank VARIETY Classification kingdom Chromista phylum Ochrophyta class Bacillariophyceae order Eunotiales family Eunotiaceae genus Eunotia species Eunotia arcubus Name Homonyms Eunotia arcus f. bidens (Grunow) Hustedt, 1957 Eunotia arcus var. bidens Grunow, 1881 Eunotia arcus var. bidens (Ehrenberg) Kirchner, 1878