Class III. POLYHYMENOPHORA Jankowski, 1967

Syns.

Membranellata p.p., Membranellophora p.p.; Polytrichidea + Oligotrichidea, Postciliodesmatophora p.p.

Oral ciliature conspicuous, with adoral zone of multiple membranelles (generally paramembranelles) especially prominent and often extending out of buccal cavity onto and/or around anterior end of body; one or more paroral membranes on the right; paucity of simple somatic ciliature (except in one major group) or with its replacement by cirri (in another group); stomatogenesis parakinetal or apokinetal; kinetodesmata rare, toxicysts and trichocysts absent; postciliodesmata common and prominent; fission almost always isotomic; conjugation temporary and isogamontic; species widely distributed, generally of large body size and diverse feeding habits, and (with one or two subgroup exceptions) very commonly free-living, free-swimming forms.

With characteristics of class (above).

Subclass Spirotricha Bütschli, 1889