Division Bacillariophyta Engl. & Gilg (1919) see Phylum Bacillariophyta Engl. & Gilg (1919)
   Class Bacillariophyceae Haeckel (1878) - pennates
     Subclass Bacillariophycidae D.G.Mann (1990) - raphid diatoms
       Order Naviculales Bessey (1907)
         Suborder Neidiineae D.G.Mann (1990)
           Family Cosmioneidaceae D.G.Mann (1990)
             Genus Cosmioneisᵀ D.G.Mann & Stickle (1990)
               1 Cosmioneis pusillaᵀ (W.Sm.) D.G.Mann & Stickle (1990)
               2 Cosmioneis delawarensis (Grunow ex Cleve) D.G.Mann (1990)
               3 ?Cosmioneis grossepunctata (Hust.) D.G.Mann (1990)
               4 Cosmioneis lundstroemii (Cleve) D.G.Mann (1990)