Circumscription: Amitochondriate parasitic Amoebae with pseudopodia as clear semieruptive bulges from anterior of cell. Forms cysts. Amitochondriate status probably secondary. Ultrastructural identity: Mitochondria absent, dictyosomes present. Small osmiophilic bodies sometimes adhering to inner surface of cell membrane. Cytoplasm with helical arrays (said to be of ribosomes), mitosis with entirely intranuclear spindle with amorphous intranuclear microtubule organizing centre. Synapomorphy: Amitochondriate Amoebae with intranuclear spindle.