Division Haptophyta Hibberd
   Class Prymnesiophyceae D.J. Hibberd (1976) see Class Coccolithophyceae Rothm. (1951)
     Subclass Prymnesiophycidae (D.J. Hibberd) Cavalier-Sm. (1986) see Class Prymnesiophyceae D.J. Hibberd (1976)
       "Nannoliths"
         Order †Discoasterales Hay (1977)
           1 Family †Discoasteraceae Tan (1927)
           2 Family †Fasciculithaceae Hay & Mohler (1967)
           3 Family †Heliolithaceae Hay & Mohler (1967)
           4 Family †Sphenolithaceae Deflandre (1952)