Family CHATTONIDIIDAE Villeneuve-Brachon, 1940

Body large and somewhat rotund, with gently pointed posterior end; buccal caviry opens apically and bears full circle of strong membranelles; stomatogenesis apokinetal, with new infraciliary bases developing in oligotrich-like pouch; macronucleus very long, with loops; a unique "posteroaxial caviry," containing cilia, opens at posterior pole; in polluted brackish waters.

Chattonidium Villeneuve, 1937. Single species.