Family Pfiesteriaceae Steidinger et al., 1996
Family within Order Dinamoebales. Species in this family have a multiphasic life cycle with polymorphic unicells of bi- and triflagellate, amoeboid and cyst stages. Bi- and triflagellate stages typically planktonic and ephemeral and resemble gymnodinioid forms, but they actually cryptic peridinioids. Amoeboid stages with filose to lobose forms. Cyst stages spherical to elongate with surface sculpture and/or scales. Transition forms occur between all stages. Chloroplasts present as cleptochloroplasts; cells capable of phagocytosis. Nutrition is heterotorphic and mixotrophic.
Genus Pfiesteria Steidinger et al., 1996