Fauré-Fremiet in Corliss, 1956
Body frequently dorsoventrally flattened and flexible; often with adhesive organelle at posterior end. Somatic ciliature composed of monokinetids and restricted mainly to ventral side. Dorsal side naked or with single ciliary row, viz. the dorsal brush. Several oral kineties anterior to oral basket (cyrtos), which is located in first half of body. Preoral suture skewed far to left. Macronucleus heteromerous (except in one suborder). Stomatogenesis telokinetal (parakinetal according to some workers), but involving extensive morphogenetic movements. Mostly marine, free-living, ectocommensals, a few parasitic on fish gills.
Suborder Chlamydodontina
Family Chlamydodontidae
Suborder Dysteriina
Family Hartmannulidae
Family Dysteriidae
Family Kryoprorodontidae