Cap 17

free-swimming; somatic kineties of ciliated diki-
netids, equally distributed around body, extend-
ing as simple files from the outer ring of serial 
oral polykinetids towards cell’s posterior ; outer 
and inner oral polykinetids typical of the subclass, 
although Parastrombidinopsis may not have com-
pletely closed outer circle when alive; macronu-
clei, ellipsoid, typically two; micronucleus, when 
observed, typically single; contractile vacuole, at 
least present in freshwater forms; cytoproct (?); 
feeding on bacteria and microalgae; typically in 
marine habitats, planktonic; one family. 
 Family STROMBIDINOPSIDAE Small & Lynn, 
1985
 With characters of the suborder; two genera. 
 – Parastrombidinopsis Kim, Jeong, Strüder-
Kypke, Lynn, Kim, Kim, & Lee, 2005 *
 – Strombidinopsis Kent, 1881 
 Subclass Stichotrichia Small & Lynn, 1985 
 (syns. Euhypotrichina , Hypotricha p.p ., Hypo-
trichea p.p ., Hypotrichida p.p ., Hypotrichina p.p ., 
 Hypotrichorida p.p .) 
 Size, small to large; shape, often elongate, 
sometimes very drawn out posteriorly, in cross-
section round to dorsoventrally compressed; free-
swimming with a few loricate forms; perilemma 
in some groups; pellicular alveoli weakly devel-
oped; somatic ventral ciliature as ventral cirri 
ranging from small and quite inconspicuous, 
occasionally as few as 2–3 cilia per cirrus, 
arranged in longitudinal, sometimes spiraled, 
files to a few, larger cirri in scattered groups, 
with in the latter case marginal files of cirri dif-
ferentiated ; transverse cirri, may or may not be 
present; caudal cirri, may or may not be present; 
dorsal somatic ciliature as one to many kineties 
– typically three – of dikinetids without kinetodes-
mal fibril, but with short, bristle cilium on anterior 
kinetosome; adoral zone of oral polykinetids as 
paramembranelles in “collar” and “lapel”, each 
typically of four rows of kinetosomes, with the 
first two rows equally long and the fourth row 
quite short; right oral cilia variable, but usually as 
a paroral and endoral; stomatogenesis, parakinetal 
in those with conspicuous kineties to apokinetal in 
those with scattered cirri; division morphogenesis 
may involve replacement of all somatic cili-
ature of both proter and opisthe ; macronucleus, 
typically two nodules, but often multiple, each 
component typically with one replication band; 
micronucleus, one to many; conjugation, typi-
cally temporary, but sometimes total; contractile 
vacuole, at least present in freshwater and ter-
restrial forms, and typically on the middle left of 
the body; cytoproct, very likely present; feeding 
strategies ranging from bacterivorous to cannibal-
istic; encysted forms typically dedifferentiate all 
kinetosomes ; in marine, freshwater, and terrestrial 
habitats, free-living with some symbiotic forms as 
endo- and ectocommensals; three orders. 
17.3 The Ciliate Taxa to Genus 357
NOTE : The taxonomy of stichotrichians is one 
of the most confused in the phylum. The revision 
below relies heavily on the morphology of the dif-
ferentiated individual. There is, however, a trend in 
recent years to rely more heavily on the similarities in 
the pattern of division morphogenesis (e.g., Berger, 
1999, 2006b; Eigner & Foissner, 1994). Stability 
may only be achieved when complete division 
morphogenetic patterns and molecular genetic 
information for several genes are available on the 
majority of genera (see Foissner et al., 2004). 
 Order Stichotrichida Fauré-Fremiet, 1961 
 (syns. Chaetospirina p.p ., Oxytrichida p.p ., Oxytri-
china p.p ., Plagiotomida p.p ., Plagiotomoidea p.p .) 
 Size, small to large; shape, often elongate, some-
times very drawn out posteriorly; free-swimming 
with a few loricate forms; ventral cirri as one or 
more longitudinal files of varied lengths, linear 
(not zig-zag as in Urostylida) ; dorsal ciliature, 
typically regularly distributed in longitudinal files; 
oral structures as for subclass; stomatogenesis, 
parakinetal or apokinetal; six families. 
 Family AMPHISIELLIDAE Jankowski, 1979 
 (syns. Gastrostylidae p.p ., Gastrostylina p.p ., 
 Orthoamphisiellidae ) 
 Size, small to large; shape, elongate ovoid; free-
swimming; ventral cirral file, single with anterior 
segment of this file formed by cirri from right-
most ventral anlage and posterior segment from 
the second ventral anlage from right ; marginal 
files of cirri, typically extending from anterior to 
posterior on left and right sides; transverse cirri, 
may or may not be present; caudal cirri, may or may 
not be present; dorsal kineties, typically fewer than 
ten, composed of dikinetids; oral structures as for 
order with paroral and endoral; macronucleus, from 
two to many globular to ellipsoid nodules; micro-
nuclei, one often accompanying each macronuclear 
nodule; contractile vacuole, present; cytoproct, 
likely present; feeding on bacteria and smaller 
protists; in marine, freshwater, and terrestrial habitats;
11 genera and two genera incertae sedis . 
 – Afroamphisiella Foissner, Agatha, & Berger, 
2002*
 – Amphisiella Gourret & Roeser, 1888 
 – Amphisiellides Foissner, 1988 
 – Hemiamphisiella Foissner, 1988 
 – Nudiamphisiella Foissner, Agatha, & Berger, 
2002*
 – Lamtostyla Buitkamp, 1977 
 – Orthoamphisiella Eigner & Foissner, 1991 
 – Paramphisiella Foissner, 1988 
 – Pescozoon Jankowski, 1978 
 – Uroleptoides Wenzel, 1953 
 – Urospinula Corliss, 1960 (subj. syn. Psilotricha ) 
Incertae sedis in Family Amphisiellidae
 – Balladyna Kowalewski, 1882 (subj. syn. 
Cyrtohymena ) 
 – Circinella Foissner, 1994 
 Family KAHLIELLIDAE Tuffrau, 1979 
 (syns. Banyulsellidae , Cladotrichidae , Lacazeidae , 
 Parakahliellidae ) 
 Size, medium to large; shape, elongate ovoid; 
free-swimming; somatic ventral ciliature with at 
least two, typically more than two, ventral cirral 
files, often not distinctly different from right and 
left marginal cirral files; ventral cirral files may 
be preserved through a variable number of 
cell divisions (= cell generations) before being 
resorbed and replaced through additional new 
(= neokinetal) anlagen ; transverse cirri, typi-
cally absent; caudal cirri, typically absent; dorsal 
ciliature as several files of dikinetids; oral ciliature 
as for order with paroral and endoral; macronu-
cleus, two to many nodules; micronuclei, several 
to many; contractile vacuole, present; cytoproct, 
likely present; feeding on bacteria, microalgae, and 
smaller protists; in marine, freshwater, and terres-
trial habitats; ten genera and four genera incertae
sedis . 
 – Cladotricha Gajewskaja, 1926 
 – Deviata Eigner, 1995 
 – Engelmanniella Foissner, 1982 
 – Kahliella Corliss, 1960 
 – Neogeneia Eigner, 1995 
 – Parakahliella Berger, Foissner, & Adam, 1985 
 – Plesiotricha Dragesco, 1970 (subj. syn. Kahliella ) 
 – Pseudokahliella Berger, Foissner, & Adam, 1985 
 – Trachelochaeta Šrámek-Husek, 1954 
 – Wallackia Foissner, 1976 
Incertae sedis in Family Kahliellidae
 – Banyulsella Dragesco, 1954 
 – Fragmocirrus Foissner, 2000 
358 17. The Ciliate Taxa Including Families and Genera
 – Lacazea Dragesco, 1960 
 – Pseudouroleptus Hemberger, 1985 
 Family KERONIDAE Dujardin, 1840 
 (syns. Keronina , Keronopsidae , Keronopsina ) 
 Size, medium; shape, from broad to elongate, 
even tailed in some species; free-swimming; 
somatic ventral ciliature as frontoventral cirri gen-
erally in several oblique rows across the ventral 
surface, coursing between right and left marginal 
cirral files; first ventral row, so-called “frontal 
cirri”, as curved row along ventral anterior 
border of left serial oral polykinetids and differ-
entiating from one to several anlagen ; transverse 
cirri, present; caudal cirri, present; dorsal somatic 
ciliature as several files of bristle dikinetids; oral 
ciliature as for order with paroral and endoral; 
cell division in cyst, except for Kerona