Domain Eucaryota
   Subdomain Chlorota Doweld (2001)
     Kingdom Bacillariobiota Doweld (2001)
       Subkingdom Prymnesiobiotina Doweld (2001) [monotypic]
         Phylum Prymnesiophyta Hibberd ex Doweld (2001)
           1 Class Pavlovophyceae J.C. Green & Medlin (2000)
           2 Class Prymnesiophyceae D.J. Hibberd (1976) see Class Coccolithophyceae Rothm. (1951)