Class Conjugatophyceae Engl. (1892) see Class Zygnematophyceae Round ex Guiry (2013) Order Zygnematales - filamentous conjugates and saccoderm desmids Family Mesotaeniaceae Genus Roya West & G.S.West (1896) Roya obtusa (Bréb.) W.West & G.S.West