Kingdom Protoctista Hogg, 1860
   Phylum Cryptophyta Caval.-Sm. (1986) - cryptomonads see Superclass Cryptomonada Cavalier-Smith, 2004
     Class Cryptophyceae F.E. Fritsch (1927)
       Order Cryptomonadales Pascher (1913)
         Genus Cyathomonas Fromentel (1874)
           1 Cyathomonas truncata (Fresenius, 1858) C. Fisch (1885) see Goniomonas truncata (G. Fresenius, 1858) F.R. von Stein (1878)