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) "Heterococcoliths" "Muroliths" 1 Order †Eiffellithales Rood, Hay & Barnard (1971) 2 Order Zygodiscales Young & Bown (1997) 3 Order Stephanolithiales (Bown & Young, 1997) 4 Order Syracosphaerales Ostenfeld (1899) 5 Order Rhabdosphaerales Ostenfeld (1899)