Class Dinophyceae Pascher (1914)
   Order Dinophysiales Kof. (1926) see Order Dinophysales Er. Lindem. (1928)
     Family Dinophysaceae F. Stein (1883)
       Genus Phalacroma F. Stein (1883)
         Phalacroma expulsum (Kofoid & Michener) Kofoid & Skogsberg