chromalveolates see Supergroup Chromalveolata Adl et al., 2005
   Kingdom Chromista Caval.-Sm. (1981) - chromists
     Subkingdom Chromobiota Caval.-Sm. (1991)
       Infrakingdom Haptophyta Caval.-Sm. (1995) [monotypic] see Subphylum Haptophytina Caval.-Sm. (2015)
         Phylum Haptophyta D.J. Hibberd ex Edvardsen & Eikrem (2000) see Subphylum Haptophytina Caval.-Sm. (2015)
           Class Prymnesiophyceae D.J. Hibberd (1976) see Class Coccolithophyceae Rothm. (1951)
             1 Genus Emiliania W.W. Hay & H. Mohler (1967)
             2 Genus Isochrysis M. Parke (1949)
             3 Genus Prymnesium J. Massart (1920)