Cap 17

in character-
istic helical coils so that the margin of the cone 
spirals at least twice around the central column, 
but may spiral up to a half a dozen full turns in 
some species ; no spines; collar, short, broad; cili-
ation with posterior part of the right field covering 
the spiralling cone and the left field at the base of 
the cone; sessile; peduncle, low and broad; macro-
nucleus, heteromerous, ellipsoid; micronucleus, 
present; contractile vacuole, possibly present; cyto-
proct, present; feeding (?); typically in freshwater 
habitats, usually on the gills of gammarid amphi-
pods ; three genera. 
 – Cavichona Jankowski, 1973 
 – Serpentichona Jankowski, 1973 
 – Spirochona Stein, 1852 
 Order Cryptogemmida Jankowski, 1975 
 (syns. Endogemmina , Dorsofragmina + Ventro-
fragmina ) 
 Size, small; shape, often flattened, leaf-like, 
and angular; spines common and of several types; 
collar, reduced; stalk, typically present, of vary-
ing length; internal budding, with up to eight 
tomites produced in a crypt or marsupium; 
macronucleus, heteromerous, with orthomere 
directed antapically away from funnel ; in marine 
habitats, occurring solely on littoral and open 
ocean crustaceans (i.e. amphipods , copepods , cya-
mids , nebaliids ), including crustacean epibionts of 
 whales ; six families. 
 Family ACTINICHONIDAE Jankowski, 1973 
 Size, small to medium; shape, sac-like, usually 
flattened; cortex, often thickened; apical end coni-
cal, not flattened, sometimes with a fold, and 
with conspicuous spines in some species; cone 
rotated 90° to right, relative to body and point of 
attachment ; collar may be elongate; ciliation with 
left field considerably reduced; sessile; peduncle, 
present, rather than stalk, with broad part of body 
often closely applied to substrate; crypt of vary-
ing size; macronucleus, heteromerous, ellipsoid; 
micronucleus, present; contractile vacuole, absent; 
cytoproct, absent; feeding (?); in marine habitats, 
exclusively on nebaliids ; six genera. 
 – Actinichona Jankowski, 1973 
 – Carinichona Jankowski, 1973 
 – Crassichona Jankowski, 1973 
 – Cristichona Jankowski, 1973 
 – Kentrochonopsis Doflein, 1897 
 – Rhizochona Jankowski, 1973 
 Family ECHINICHONIDAE Jankowski, 1973 
 Size, small to medium; shape, rhombic or spin-
dle-like, markedly flattened dorsoventrally; cone 
flattened, not rotated; cone with smooth wall and 
small teeth on its margins ; collar distinct, nar-
row, low; ciliation with long and narrow right 
field and very reduced left field ; sessile; stalk, 
quite long in some species; crypt, very deep and 
broad ; macronucleus, heteromerous, ellipsoid; 
micronucleus, present; contractile vacuole, absent; 
cytoproct, absent; feeding (?); in marine habitats, 
on nebaliids ; three genera. 
 – Coronochona Jankowski, 1973 
 – Echinichona Jankowski, 1973 
 – Eurychona Jankowski, 1973 
 Family INVERSOCHONIDAE Jankowski, 1973 
 (syn. Pleochonidae ) 
 Size, small to medium; shape, sometimes elon-
gate, flattened dorsoventrally; very heavy, well-
developed body spines in some species; apical
end very broad, flattened, usually simple, but 
occasionally with a few spines ; cone flattened, 
not rotated; collar, distinct; ciliation with left field 
larger than right field, which may be subdivided 
into two components ; sessile; peduncle, exceed-
ingly short; crypt relatively shallow ; macro-
nucleus, heteromerous, elongate; micronucleus, 
present; contractile vacuole, absent; cytoproct, 
absent; feeding (?); in marine habitats, on nebali-
ids ; five genera. 
 – Ceratochona Jankowski, 1973 
 – Chonosaurus Jankowski, 1973 
 – Inversochona Jankowski, 1973 
 – Kentrochona Rompel, 1894 
 – Pleochona Jankowski, 1973 
 Family ISOCHONIDAE Jankowski, 1973 
 Size, medium; shape, cylindrical, elongate, not 
flattened; cone, rounded, simple, funnel-shaped, 
rather small and undistinguished, and in line 
386 17. The Ciliate Taxa Including Families and Genera
with main axis of long body ; collar, short; cili-
ation with right field not subdivided and left field 
relatively large; sessile; stalk, sometimes long; 
crypt of moderate size; macronucleus, heteromer-
ous, ellipsoid; micronucleus, present; contractile 
vacuole, absent; cytoproct, absent; feeding (?); 
in marine habitats, with very wide distribution 
on appendages or shell of amphipods , nebaliids , 
and cyamids , including the “ whale-lice ” found on 
species of several genera of whales from various 
oceans; five genera 
 – Cyamichona Jankowski, 1971 
 – Inermichona Jankowski, 1971 
 – Isochona Jankowski, 1973 
 – Thalassochona Jankowski, 1971 
 – Trichochona Mohr, 1948 
 Family ISOCHONOPSIDAE Batisse & 
Crumeyrolle, 1988 
 Size, small to medium; shape, cylindrical, elon-
gate; cone, rounded, funnel-shaped, in line with 
main axis of long body; cone margin indented by 
flexible folds that are able to close the opening 
to the oral region ; collar, short; ciliation with left 
field and a right field, which is subdivided into an 
horizontal upper band and an oblique lower band; 
sessile; peduncle, short; macronucleus, heteromer-
ous, ellipsoid; micronucleus, present; contractile 
vacuole, absent; cytoproct, connected by tube to 
the cell surface; feeding (?); in marine habitats, on 
the periopods of copepods ; one genus. 
 – Isochonopsis Batisse & Crumeyrolle, 1988 
 Family STYLOCHONIDAE Mohr, 1948 
 Size, small to medium; shape, triangular or 
rhomboid, leaf-like, markedly flattened dorsoven-
trally, spines, may be large, elongate or may be as 
rows of papillae; cone, flattened, not rotated; conal
margin often spiny, with pockets and folds in 
conal wall ; collar, very short; ciliation with larger 
right field and a left field that may be reduced to 
an almost vertical band; sessile; stalk, of varying 
length, sometimes unusually long; crypt, often 
very deep ; macronucleus, heteromerous, ellipsoid; 
micronucleus, present; contractile vacuole, absent; 
cytoproct, absent; feeding (?); in marine habitats, 
on nebaliids; ten genera. 
 – Armichona Jankowski, 1973 
 – Ctenochona Jankowski, 1973 
 – Dentichona Jankowski, 1973 
 – Eriochona Jankowski, 1973 
 – Flectichona Jankowski, 1973 
 – Oxychonina Corliss, 1979 
 – Paraoxychona Jankowski, 1973 
 – Pterochona Jankowski, 1973 
 – Spinichona Jankowski, 1973 
 – Stylochona Kent, 1881 
 Subclass Rhynchodia Chatton & Lwoff, 1939 
 (syns. Rhynchodea p.p ., Toxistomia p.p .) 
 Size, small to rarely medium; shape, ovoid, 
somewhat flattened, typically with pointed ante-
rior end; free-swimming, but if parasitic, typically 
attached to host tissue; adult forms, either devoid 
of somatic ciliature or with it mostly restricted to 
an anteroventral thigmotactic field; oral region not 
bounded by oral kinetal structures; oral appa-
ratus a suctorial tube supported only by phyl-
lae ; oral extrusomes, as toxic (?) acmocysts or 
haptotrichocysts ; reproduction, isotomic fission 
or often by budding; larval forms typically with 
two ciliated fields; macronucleus, homomerous; 
micronucleus, often large, sometimes multiple; 
predators of other ciliates, especially suctorians 
and peritrichs, or parasitic (?) on gills or mouth-
parts of diverse invertebrates in marine and fresh-
water habitats, but most often on gills of marine 
 bivalve molluscs ; two orders. 
NOTE : The classic monographs on this group 
are by Chatton and Lwoff (1949, 1950). Raabe 
(1970b) provided the last major taxonomic treat-
ment.
 Order Hypocomatida Deroux, 1976 
 (syns. Hypocomatina , Hypocomida , Hypocomina 
+ Macrostomatina ) 
 Size, small; shape, dorsoventrally flattened; 
somatic kineties, essentially restricted to the 
ventral surface with a short anterio-lateral left 
kinety, a presumed homologue of the dorsal 
right kinetofragment of cyrtophorines; poste-
rior adhesive region bounded by somatic kine-
ties in right-ventral pit or fosette ; oral ciliature,