adhesive region at posterior tip of cell; oral ciliature as one preoral and two circumoral kinetofragments in a deep oral cavity ; macronucleus, juxtaposed heteromer- ous, elongate ellipsoid; micronucleus, present; contractile vacuole (?); cytoproct, present; feeding on organic detritus and sometimes epithelial cells of host; in marine habitats, known so far only as ectosymbionts of in the nasal cavities of ceta- ceans, and collected from the mucus discharged from the blowholes of living or dead hosts ; two genera. – Kyaroikeus Sniezek, Coats, & Small, 1995 – Planilamina Ma, Overstreet, Sniezek, Solangi, & Coats, 2006 * Family PLESIOTRICHOPIDAE Deroux, 1976 Size, small to medium; shape, ovoid to elongate, somewhat dorsoventrally compressed; free-swim- ming, but may temporarily attach by podial fila- ment; somatic ciliation with right ventral kineties arcing preorally to left, and a field of left ventral kineties abutting at a preoral suture system; oral ciliature varying from a preoral and two circumoral kinetofragments to multiple circumoral kinetof- ragments; ventral adhesive region, glandular, non-ciliated (except in Atelepithites ), but may secrete podial filament ; macronucleus, juxtaposed heteromerous, ellipsoid; micronucleus, present; contractile vacuole, may be multiple; cytoproct (?); feeding on bacteria and microalgae; in marine habitats; five genera. – Atelepithites Deroux, 1976 – Parachilodonella Dragesco, 1966 – Pithites Deroux & Dragesco, 1968 – Plesiotrichopus Fauré-Fremiet, 1965 – Trochochilodon Deroux, 1976 Incertae sedis in Subclass Cyrtophoria – Dysterioides Matthes, 1950 Subclass Chonotrichia Wallengren, 1895 (syns. Phyllopharyngidea p.p ., Scaiotricha p.p .) Size, small to medium; shape, often vase-shaped, with pellicle quite rigid and frequently adorned with collar, lobes, and/or spines; sessile and sedentary, except as dispersive larval forms; posterior adhe- sive organelle or podite produces stalk or peduncle, always non-contractile; somatic kineties only on walls of perioral funnel or cone-shaped region, which may be flared, or compressed ; somatic kineties in two fields – a right field whose kine- ties are typically arrayed parallel to the margin of the cone and a left field whose kineties are typically arranged obliquely to the margin of the cone ; oral cilia, apparently absent or only as several inverted kineties next to the cytostome; cytopharyngeal apparatus with phyllae, but no nematodesmata ; reproduction solely by unequal division or budding, within a crypt or “marsupium” in one order; polygemmy may occur on death of host; migratory larval forms or tomites bear an adhesive gland posteriorly and two fields of cilia on deep concave ventral surface or gutter, remi- niscent of their putative ancestry among the cyr- tophorine-like forms ; conjugants, of unequal size, invariably undergoing total fusion; macronucleus, heteromerous; contractile vacuoles, when present, connected to body surface by an excretory canal; cytoproct, may be present; microphagous, typically feeding on bacteria and food particles derived from host; in marine, brackish, and freshwater habitats as ectosymbionts on the gills, mouthparts, and/or other appendages of crustaceans , principally amphi- pods , isopods , and copepods , but also decapods , nebaliids , and others, with one species attaching to a marine alga; two orders. NOTE : The monograph of Jankowski (1973b) still stands as the major modern treatise on this group. Batisse (1994a) has provided a revision, including a new order (i.e. Order Chilodochonida ), which we do not recognize. Molecular genetic evidence may justify its distinctness. We have maintained the divisions based on the kind of bud- ding (e.g., external budding and internal budding) as proposed by Jankowski (1973b). 384 17. The Ciliate Taxa Including Families and Genera Order Exogemmida Jankowski, 1972 (syn. Chilodochonida p.p ., Lobochonina p.p., Spirochonina p.p.) Shape, typically long and cylindrical, and typi- cally with a well-developed collar (except Family Chilodochonidae ); spines absent or poorly devel- oped; usual attachment by undistinguished pedun- cle (rather than “true” stalk, except in Family Chilodochonidae ); a few to several tomites or buds produced by external budding; macronu- cleus, heteromerous, with orthomere directed apically towards funnel ; six families. Family CHILODOCHONIDAE Wallengren, 1895 Size, medium; shape, ovoid or pyriform, mas- sive, not flattened; apical end large, cylindrical, flaring slightly; collar indistinct or absent ; no spines; sessile; cortex, markedly thickened; long, wide, solid stalk, rather than peduncle typical of order ; somatic ciliature as two subparallel ciliary fields; oral ciliature as a circumoral kinety border- ing the left side of the cytostome; macronucleus, heteromerous, elongate; micronucleus, present; contractile vacuole, absent; cytoproct, absent; feed- ing (?); in marine habitats on the mouthparts of decapods in littoral and sublittoral habitats; two genera. – Chilodochona Wallengren, 1895 – Vasichona Jankowski, 1972 Family FILICHONIDAE Jankowski, 1973 Size, medium; shape, cylindrical or bottle- shaped, not flattened, with simple apical end, conical and unadorned; sessile; collar distinct and markedly elongate, with spine-like processes on hypocollar between collar and body ; peduncle, low and broad; macronucleus, heteromerous, ellip- soid; micronucleus, present; contractile vacuole, absent; cytoproct, absent; feeding (?); in marine habitats on isopods ; two genera. – Aurichona Jankowsi, 1973 – Filichona Jankowski, 1973 Family HELIOCHONIDAE Jankowski, 1972 Size, small to medium; shape, bottle-like, elon- gate to sac-like, not flattened; sessile; cone a simple funnel that may have spines of different structure on each side of cone ; collar, distinct, usually short; somatic ciliature as a left field and larger right field, which is subdivided into an upper horizon- tal component of usually <6 kineties and a lower oblique component ; peduncle, short; macronucleus, heteromerous, ellipsoid; micronucleus, present; con- tractile vacuole, may be present; cytoproct, absent; feeding (?); in marine or brackish habitats, particu- larly on gammarid amphipods ; two genera. – Heliochona Plate, 1889 – Heterochona Jankowski, 1972 Family LOBOCHONIDAE Jankowski, 1967 Size, medium; shape, elongate, bottle-like, not flattened; sessile; apical end simple, conical, slightly flared, often with two dorsal lobes; cone a simple funnel ; collar, distinct; ciliation as a left field and a larger right field, which is divided, having >6 kineties in each part ; peduncle, short, distinct; macronucleus, heteromerous, ellipsoid; micronucleus, present; contractile vacuole, absent; cytoproct, absent; feeding (?); only in marine or brackish habitats – but with very wide distribution – on isopods and amphipods , with one unique spe- cies on an alga; five genera. – Lobochona Dons, 1941 – Oenophorachona Matsudo & Mohr, 1968 – Physochona Batisse & Crumeyrolle, 1988 – Segmentochona Jankowski, 1989 – Toxochona Jankowski, 1972 Family PHYLLOCHONIDAE Jankowski, 1972 Size, small; shape, leaf-like, not elongate, flattened dorsoventrally, contorted; cone with leaf-shaped preoral outgrowths ; collar absent; ciliation as two fields; sessile; peduncle in form of wide disc; macronucleus, heteromerous, mas- sive ; micronucleus, present; contractile vacuole, absent; cytoproct, absent; feeding (?); in marine habitats on isopods ; one genus. – Phyllochona Jankowski, 1972 Family SPIROCHONIDAE Stein, 1854 Size, small to medium; shape, vase-like, elon- gate, typically not flattened; apical end flared, 17.3 The Ciliate Taxa to Genus 385 with dorsal wall multiply-spiraled