Class Conjugatophyceae Engl. (1892) see Class Zygnematophyceae Round ex Guiry (2013) Order Zygnematales - filamentous conjugates and saccoderm desmids Family Mesotaeniaceae Genus Ancylonema Berggr. (1871) [monotypic] Ancylonema nordenskioeldii Berggr.