Subclass Flabellinia Smirnov et al. 2005


Diagnosis: Flattened generally fan-shaped, discoid or irregularly triangular, never with pointed subpseudopodia or centrosomes.


  • Pellitida
    Thick cell coat does not contain scales, is integrated with the cell membrane, and envelops the entire cell or part of the cell, leaving dorsal surface free.


  • Dactylopodida
    Locomotory form as irregular triangle with basement directed forward; wide anterior hyaloplasm; parasomes in Paramoeba and Neoparamoeba; cysts unknown; without fibrous axial cores both in dactylopodia and in the floating pseudopodia; cortex with extracellular scales, pentagonal or hexagonal glycostyles or a complex fibrous “cuticle”.
    Incertae sedis Dactylopodida: Boveella, Dactylosphaerium, Oscillodignum, Podostoma, Strioluatus, Subulamoeba,Trienamoeba.


  • Vannellida
    Locomotion as fan-shaped to spatulate cell; without discrete pseudopodia or subpseudopodia; wide anterior hyaloplasm up to half of the cell; posterior granuloplasm concentrated in a “hump”, often raised over the substratum; cell coat is a layer of hexagonal prismatic structures (Platyamoeba), with short glycostyles on top (Clydonella, Lingulamoeba) or pentagonal glycostyles with or without simple filaments (Vannella); one taxon known to be sporocarpic and protosteloid.
    Incertae sedis Vanellida: Discamoeba, Unda.


  • Himatismenida
    Flattened highly mobile amoebae, covered dorsally with a coat independent on the cell membrane or small low mobile globular amoebae with a dorsally irregularly wrinkled and semi-rigid thick cell coat.


  • Trichosphaerium
    Cell enveloped with flexible membranous shell (smooth form) or rigid envelope bearing spicules (spicule-bearing form); both types of envelopes are separated from the cell membrane; the amoeba protrudes through this envelope with temporary openings, producing finger-shaped dactylopodia.