Apicomplexa which exist as predatory flagellates using an apical complex to attack their prey. Colpodella and Acrocoelus are admitted. They feed by sucking up the cytoplasm through a rostrum, other flagellate genera exhibiting this behaviour have been assigned to other genera including Spiromonas, Dinomonas, Alphamonas, Nephromonas, Dingensia and Bodo; and all may be synonyms. References: Brugerolle & Mignot, 1979, Foissner & Foissner, 1984, Krylov & Mylnikov, 1986, Mylnikov, 1991.