Cap 17

in Corliss, 
1979
 Size, medium to large; shape, elongate and 
radially symmetrical; free-swimming; somatic 
ciliation, holotrichous with polar anterior suture 
separated from oral region and synhymenium; syn-
hymenium, extending almost completely around 
body circumference just below level of the cyto-
stome-cytopharyngeal apparatus ; cytostome in 
anterior 1/4 of body; macronucleus, globular to 
ellipsoid; micronucleus, present; contractile vacu-
ole, medially located on ventral surface; feeding 
on diatoms, other microalgae, and cyanobacteria ; 
in marine, freshwater, and occasionally terrestrial 
habitats; two genera. 
 – Beersena Jankowski, 1989 (for preoccupied 
Phasmatopsis Deroux, 1978) 
 – Nassulopsis Foissner, Berger, & Kohmann, 1994 
 Family ORTHODONELLIDAE Jankowski, 1968 
 Size, small to medium; shape, roughly ovoid, 
sometimes with asymmetrical lobe or beak to 
the left; free-swimming; somatic ciliation, hol-
otrichous; synhymenium, thickly ciliated, 
extending from right postoral body surface, 
just below level of the cytostome-cytopharyn-
geal apparatus, to left preoral body surface 
into preoral suture, which is formed by right 
somatic kineties extending around anterior end 
onto the left side ; cytostome in anterior 1/4 of 
body; macronucleus, ellipsoid to elongate band-
form; micronucleus, present; contractile vacuole, 
present; feeding on diatoms , other microalgae, 
and cyanobacteria ; predominantly in marine and 
brackish habitats; two genera and one genus 
incertae sedis . 
 – Orthodonella Bhatia, 1936 
 – Zosterodasys Deroux, 1978 
Incertae sedis in Family Orthodonellidae 
 – Eucamptocerca da Cunha, 1914 [nomen dubium] 
 Family SCAPHIDIODONTIDAE Deroux in 
Corliss, 1979 
 Size, small; shape, somewhat dorsoventrally 
flattened with slightly broader anterior end and 
gently tapered posterior; free-swimming; somatic 
ciliation, holotrichous, but reduced on much of the 
dorsal surface of Scaphidiodon ; synhymenium or 
hypostomial frange, sparsely ciliated, extending 
from only slightly right postoral region onto 
left preoral body surface into preoral suture ; 
cytostome in anterior 1/4 of body; macronucleus, 
globular to ellipsoid; micronucleus, present; con-
tractile vacuole, present; feeding on diatoms , other 
microalgae, and cyanobacteria ; in marine and 
freshwater habitats; two genera. 
 – Chilodontopsis Blochmann, 1895 
 – Scaphidiodon Stein, 1859 
 Family SYNHYMENIIDAE Jankowski in Small 
& Lynn, 1985 
 Size, medium; shape, elongate; free-swimming; 
somatic ciliation, holotrichous; synhymenium or 
hypostomial frange, extending into a left preoral 
suture and also with a second preoral suture to 
right of the first, into which synhymenium does 
not extend ; cytostome in anterior 1/4 of body; 
macronucleus, ellipsoid; micronucleus (?); con-
tractile vacuole, present; feeding (?); in freshwater 
habitats; one genus. 
NOTE : This family and genus need careful 
redescription.
 – Synhymenia Jankowski, 1968 
 Order Nassulida Jankowski, 1967 
 (syns. Ambihymenida , Cyrtohymenostomatida p.p ., 
 Parahymenostomatida , Paranassulida , Pronassulida 
p.p .) 
 Size, small to large; shape, elongate, ovoid; alve-
olocysts, present; somatic ciliation, holotrichous, 
usually dense with kineties closely adjacent; distinct 
preoral suture; somatic kinetosomes with a proxi-
mal and distal cartwheel ; somatic extrusomes, 
rod-like, when present; synhymenium or hypos-
tomial frange, beginning in postoral region, 
always to right of the stomatogenic kinety, and 
extending to lateral left onto dorsal surface, 
but sometimes reduced to 3–4 polykinetids 
398 17. The Ciliate Taxa Including Families and Genera
restricted to a shallow oral cavity ; cyrtos, typi-
cally large, with complete palisade of nematodes-
mata; cystment, common; three families. 
 Family FURGASONIIDAE Corliss, 1979 
 (for Cyclogrammidae ) 
 Size, small to medium; shape, ovoid to ellipsoid; 
free-swimming; somatic ciliation, holotrichous; 
somatic extrusomes as fusiform trichocysts; oral
region in anterior 1/3 of the body with one to 
three left oral polykinetids and one short, right 
paroral in the oral area, but not confined to 
an oral cavity ; cyrtos, conspicuous, surrounding 
cytostome-cytopharynx; macronucleus, globular to 
ellipsoid; micronucleus, present; contractile vacu-
ole, midventral; feeding on bacteria and smaller 
protists, including microalgae; typically in fresh-
water, but sometimes terrestrial, habitats; four 
genera.
 – Furgasonia Jankowski, 1964 
 – Parafurgasonia Foissner & Adam, 1981 
 – Urliella Foissner, 1989 
 – Wolfkosia Foissner, Agatha, & Berger, 2002 *
 Family NASSULIDAE de Fromentel, 1874 
 (for Odontoholotrichidae ; syns. Cyrtohymen-
ostomatidae , Enigmostomatidae , Liosiphonidae ) 
 Size, small to large; shape, roughly ellipsoid; 
free-swimming; somatic ciliation, holotrichous, 
dense; synhymenium hypostomial frange, with 
few to many polykinetids composed of at least 
four kinetosomes extending from postoral 
region to left, sometimes onto dorsal surface ; 
paroral dikinetids sometimes conspicuous; cyrtos, 
prominent, surrounding cytostome-cytopharynx 
in anterior 1/3 of body; macronucleus, globular 
to ellipsoid; micronucleus, present; contractile 
vacuole, typically single, midventral; algivorous; 
in marine, occasionally brackish, and freshwater 
habitats, widespread; five genera and three genera 
incertae sedis . 
 – Nassula Ehrenberg, 1834 
 – Nassulides Foissner, Agatha, & Berger, 2002 *
 – Naxella Fryd-Versavel, Iftode, & Deroux, 1980 
 – Obertrumia Foissner & Adam, 1981 
 – Rhinakis Iftode, Fryd & Deroux in Deroux, 
1994 
Incertae sedis in the Family Nassulidae 
 – Archinassula Kahl, 1935 
 – Chilodina Srämek-Husek, 1957 
 – Stomatophrya Kahl, 1933 
 Family PARANASSULIDAE Fauré-Fremiet, 1962 
 (syns. Enneameronidae , Gullmarellidae ) 
 Size, medium, typically >100 µm long; shape, 
ovoid to elongate-ovoid; free-swimming; somatic 
ciliation, holotrichous; oral region in anterior 1/4 
of cell with oral structures as 3–4 polykinetids 
to the left of the cytostome in a shallow oral 
pit ; cyrtos, conspicuous; macronucleus, ellipsoid 
to ribbon-like; micronucleus, present; contractile 
vacuole, on dorsal surface; feeding (?); in marine 
habitats; two genera and one genus incertae sedis . 
 – Enneameron Jankowski, 1964 (subj. syn. 
Nassulopsis ) 
 – Paranassula Kahl, 1931 
Incertae sedis in Family Paranassulidae 
 – Gullmarella Fenchel, 1964 
 Order Microthoracida Jankowski, 1967 
 (syns. Cyrtopharyngina , Microthoracina , Prop-
eniculida ) 
 Size, small to medium, usually <100 µm long; 
shape, frequently broadly ellipsoidal, with right 
side more rounded, occasionally crescentic, and 
often laterally flattened; alveolocysts, present; 
pellicle, firm and rigid, with thickened epiplasm 
in some forms; somatic ciliation, holotrichous, 
but typically with a few somatic kineties, sepa-
rated by wide interkinetal spaces, composed of 
monokinetids, dikinetids, but polykinetids in 
the Family Discotrichidae; somatic extrusomes 
as fibrous trichocysts with anchor-like tip 
(fibrocysts), except in Family Discotrichidae ; 
oral cavity, usually three left oral polykinetids, 
with oral cavity sometimes displaced to posterior 
due to differential growth of cortex; right paro-
ral dikinetid, variably developed, but its ves-
tige always appears in stomatogenesis ; cyrtos, 
small, with complete palisade of nematodesmata; 
often cyst-forming; microphagous and algivo-
rous; typically in freshwater and terrestrial habi-
tats, but Discotricha is marine; three families. 
17.3 The Ciliate Taxa to Genus 399
 Family DISCOTRICHIDAE Jankowski, 1967 
 Size, small; shape, slightly reniform; free-
swimming; cortex, forming papillae distributed 
between somatic kineties; somatic kineties com-
posed of cirrus-like polykinetids, most of more 
than four kinetosomes, distributed