Cap 17

protuberances along the 
left side of the anterior ciliated cavity ; macro-
nucleus, globular to ellipsoid; micronucleus, 
present; contractile vacuole, one to several; in 
terrestrial habitats as endocommensals in the 
digestive tract of domestic and wild guinea 
pigs ; one genus. 
 – Cyathodinium da Cunha, 1914 
 Family DENDROCOMETIDAE Haeckel, 1866 
 Size, small to medium; trophont, hemispheri-
cal or disc-shaped; tentacles, with conical or 
tapered tips, ramified, and borne on arms 
or trunks ; swarmers, lenticular; macronucleus, 
globular to ellipsoid; micronucleus, present; con-
tractile vacuole, present; in freshwater habitats as 
ectocommensals on gammarid amphipods ; two 
genera.
 – Dendrocometes Stein, 1852 
 – Niscometes Jankowski, 1987 [not listed in 
Aescht]
 Family DISCOPHRYIDAE Collin, 1912 
 (syns. Coronodiscophryidae , Cyathodiscophryidae ,
 Multifasciculatidae ) 
 Size, small to medium; trophont, with flattened 
disc-like body, rarely sac-like; with or without 
stalk; without lorica; tentacles, capitate, in fas-
cicles or evenly distributed; swarmer, typically 
large, flattened, or elongate ovoid, with somatic 
kineties typically marginal, in two fields ; macro-
nucleus, ellipsoid, ribbon-like or ramified; micro-
nucleus, present; contractile vacuole, multiple as 
a rule; in freshwater habitats, in the periphyton, 
but many species ectocommensal on adult crusta-
ceans and the larval forms of aquatic insects; four 
genera.
 – Discophrya Lachmann, 1859 
 – Misacineta Jankowski, 1978 (subj. syn. 
Discophrya ) 
 – Multifasciculatum Goodrich & Jahn, 1943 
 – Setodiscophrya Jankowski, 1981 (subj. syn. 
Discophrya ) 
 Family ENCHELYOMORPHIDAE Augustin & 
Foissner, 1992 
 Size, small; trophont, ovoid to spheroid ; without 
stalk; without lorica; tentacles, rod-like, randomly 
distributed on one side of body; budding occurring 
evaginatively, usually in pairs; swarmer, spin-
dle-shaped, with several rod-like tentacles and 
“transverse” kineties ; macronucleus, globular; 
micronucleus, present; contractile vacuole, present; 
hydrogenosomes, present ; in brackish, freshwater, 
and terrestrial habitats, especially anaerobic ones, 
such as activated sludge; one genus. 
 – Enchelyomorpha Kahl, 1930 
 Family HELIOPHRYIDAE Corliss, 1979 
 Size, small to medium; trophonts, discoid, 
often with flattened body, attached directly to 
the substrate by tectinous adhesive disc ; ten-
tacles, knobbed, extensible, solitary or arranged 
in several fascicles; macronucleus, ellipsoid or 
ramified; micronucleus, present; contractile vacu-
ole, multiple, around periphery of cell; in fresh-
water habitats, free-living in the periphyton or as 
ectocommensals on invertebrates; two genera. 
 – Cyclophrya Gönnert, 1935 
 – Heliophrya Saedeleer & Tellier, 1930 
 Family PERIACINETIDAE Jankowski, 1978 
 (syns. Caracatharinidae , Catharinidae ) 
 Size, small to medium; trophont, laterally flat-
tened or rarely sac-like ; lorica or stylotheca, 
tectinous ; tentacles, clavate, arranged in fascicles; 
macronucleus, ellipsoid, ribbon-like or ramified; 
micronucleus, present; contractile vacuoles, typi-
cally several; in freshwater habitats, free-living in 
the periphyton or as ectocommensals on inverte-
brates; four genera. 
 – Elatodiscophrya Jankowski, 1978 (subj. syn. 
Discophrya ) 
 – Kormosia Dovgal, 2002 *
 – Periacineta Collin, 1909 (subj. syn. 
Discophrya ) 
 – Peridiscophrya Nozawa, 1938 
 Family PRODISCOPHRYIDAE Jankowski, 1978 
 Size, small; trophont, spheroid; stalked; ten-
tacles, capitate, evenly distributed over the body 
396 17. The Ciliate Taxa Including Families and Genera
surface; macronucleus, globular; micronucleus, 
present; conjugation, anisogamous, with ciliated 
microconjugant similar to a swarmer ; contrac-
tile vacuole, present; in freshwater habitats in 
periphtyon; one genus. 
 – Prodiscophrya Kormos, 1935 
 Family RHYNCHOPHRYIDAE Jankowski, 1978 
 Size, small; trophont, laterally flattened, elon-
gate; stalked; tentacles, several, agile and con-
tractile ; macronucleus, ribbon-like; micronucleus, 
present; contractile vacuole, multiple; in fresh-
water habitats as ectoparasites of discophryid
suctorians ; one genus. 
 – Rhynchophrya Collin, 1909 
 Family STYLOCOMETIDAE Jankowski, 1978 
 (syn. Discosomatellidae ) 
 Size, small to medium; trophont, ovoid, sac-
like or disc-like, spread over the substrate; some 
stalked forms; tentacles, rod-like, unramified, 
evenly distributed or arranged in rows ; macro-
nucleus, elongate ellipsoid; micronucleus, several; 
contractile vacuole, present; in freshwater habitats 
as ectocommensals on isopod and amphipod crus-
taceans ; three genera. 
 – Discosomatella Corliss, 1960 
 – Echinophrya Swarczewsky, 1928 
 – Stylocometes Stein, 1867 
 Family TRYPANOCOCCIDAE Dovgal, 2002 
 (syn. Tripanococcidae ) 
 Size, small; trophont, sac-like; without stalk; 
tentacles, absent ; swarmer, ellipsoid, laterally 
flattened, with several longitudinal kineties; 
swarmer, produced by sequential polyinver-
sogemmy ; macronucleus, globular; micronucleus, 
present; contractile vacuole, present; in freshwater 
habitats as parasites of the tissues of rotifers ; 
one genus. 
 – Trypanococcus Stein in Zacharias, 1885 
Incertae sedis in Class PHYLLOPHARYNGEA 
 – Silenella Fenchel, 1965 
 Class NASSOPHOREA Small & Lynn, 1981 
 (syns. Clinostomata p.p ., Cyrtostomata p.p ., 
 Gymnostomatida-Cyrtophorina , Gymnostomorida 
p.p ., Homotricha p.p ., Hypostomatida , 
 Hypostomea p.p ., Hypostomina , Hypostomata p.p ., 
 Parahymenostomata p.p .) 
 Size, small to large; shape, flattened dorsov-
entrally or cylindrical; free-swimming; somatic
alveoli well-developed with paired alveolocysts 
present in at least two orders – the Nassulida 
and Microthoracids ; somatic ciliation, very dense 
to often reduced in smaller forms; somatic cilia as 
monokinetids, dikinetids, or polykinetids; monoki-
netid with anterior, tangential transverse ribbon, a 
divergent postciliary ribbon, and anteriorly directed 
kinetodesmal fibril; for dikinetids, only the anterior 
kinetosome has a transverse ribbon while the pos-
terior kinetosome has a postciliary ribbon and kine-
todesmal fibril; polykinetids are cirrus-like in one 
family, the Discotrichidae ; somatic extrusomes as 
fibrocysts, fibrous trichocysts or rod-shaped muco-
cysts; cytostome ventral; cytopharyngeal appara-
tus typically of the cyrtos type, well-developed 
in several groups ; oral area may be sunk into an 
atrium, with more or less organized atrial ciliature; 
oral polykinetids with alveoli between kineto-
somal rows, may be confined to oral area or 
extend around body as hypostomial frange or 
synhymenium ; stomatogenesis, mixokinetal, and 
morphogenesis of fission may be complex; macro-
nucleus, typically homomerous; micronuclei, one 
to several; conjugation, temporary; contractile 
vacuoles, often multiple; cytoproct, typically mid-
ventral; microphagous to algivorous; in marine, 
brackish, freshwater, and terrestrial habitats, with 
ecto- and endocommensals also common, usually 
with invertebrate hosts; three orders and one order 
incertae sedis . 
 Order Synhymeniida de Puytorac et al. in Deroux, 
1978 
 (for Synhymenida ; syns. Nassulopsida , Nass-
ulopsina , Scaphidiodontida , Scaphidiodontina , 
 Synhymen[i]ina ) 
 Size, small to medium; shape, cylindrical; 
somatic ciliation, typically holotrichous with 
bipolar kineties; hypostomial frange or synhy-
menium of dikinetids or small polykinetids (i.e., 
17.3 The Ciliate Taxa to Genus 397
usually of 4 kinetosomes), extending from right 
 postoral body surface to left dorsal body sur-
face, almost encircling the body in some forms ; 
no atrium; cyrtos, conspicuous; free-living, pre-
dominantly freshwater forms, though some marine 
and a number interstitial species; four families. 
 Family NASSULOPSIDAE Deroux