Cap 17

1928 
 – Nyctotherus Leidy, 1849 
 – Paracichlidotherus Grim, 1992 
 – Paranyctotherus Sandon, 1941 (subj. syn. 
Balantidium ) 
 – Pronyctotherus Albaret & Njiné, 1976 
 – Pygmotheroides Affa’a, 1980 
 – Vesonyctus Jankowski, 1978 
 Family SICUOPHORIDAE Amaro, 1972 
 Size, medium to large; shape, plump-ovoid to 
ellipsoid, occasionally tailed; inferior (= right) con-
cave surface in part or whole as “sucker” with 
366 17. The Ciliate Taxa Including Families and Genera
supporting polysaccharide skeletal elements, 
which may also extend to support other parts 
of the body; somatic ciliation, holotrichous, with 
one apical right secant system and one caudal 
right secant system ; oral ciliature running from 
near-apical to sub-equatorial position, in a sigmoid-
like curve as it enters conspicuous infundibulum; 
macronucleus, ellipsoid, large, compact, in ante-
rior half of body, supported by more or less well-
developed karyophore; micronucleus, present; con-
tractile vacuole (?); cytoproct (?); feeding (?); in 
freshwater and terrestrial habitats as endosymbionts 
in the digestive tracts of vertebrate hosts only, such 
as amphibians and reptiles ; seven genera. 
 – Albaretia Affa’a in Aescht, 2001 
 – Geimania Albaret, 1975 
 – Metasicuophora Albaret, 1973 
 – Parasicuophora Albaret, 1968 
 – Prosicuophora de Puytorac & Oktem, 1967 
 – Sicuophora de Puytorac & Grain, 1969 
 – Spiroperistomatus Amaro & Sena, 1967
 Class LITOSTOMATEA Small & Lynn, 1981 
 (syns. Apicostomata p.p ., Homotricha p.p ., 
 Transversonematophora p.p .) 
 Size, small to large; shape, varied; free-swim-
ming; alveoli, poorly to well-developed; somatic 
ciliation, holotrichous to sparse in pleurostomes 
and some endosymbionts; somatic monokinetids, 
typical, with laterally directed kinetodesmal 
fibril that does not overlap those of adjacent 
kineties, slightly convergent postciliary ribbon, 
and two transverse ribbons, one of which is 
tangential to the kinetosome perimeter and 
extends anteriorly into the somatic ridge to the 
left of the kinetid while the other transverse rib-
bon is radial to the kinetosome perimeter and 
extends transversely into the adjacent somatic 
ridge ; one to several dorsal somatic kineties 
differentiated as a brosse or brush kinetids 
with specialized dikinetids bearing clavate cilia ; 
lamina corticalis or ecto-endoplasmic fibrillar layer 
often present and well-developed; oral ciliature as 
simple kinetids from which nematodesmata arise 
to support the cytopharynx, but nematodesmata 
may also arise from so-called “oralized” somatic 
kinetids adjacent to the oral region, and in some 
symbionts, oral ciliature is organized into polyki-
netid-like structures called syncilia; stomatogen-
esis, telokinetal; macronucleus, typically single, 
variously shaped from globular to band-shaped or 
moniliform; micronucleus, present; conjugation, 
temporary; contractile vacuole, present; cytoproct, 
present; feeding, extremely diverse, on bacteria 
and plant debris in some symbionts to carnivorous 
in others; in marine, freshwater, and terrestrial 
habitats, free-living and as endosymbionts in wide 
variety of vertebrates, especially; two subclasses. 
 Subclass Haptoria Corliss, 1974 
 (syns. Acrostomatina , Haptorida , Paramastigina 
p.p ., Prionostomatina , Raptorida , Rhynchostomata 
p.p ., Rhynchostomatida p.p ., Sciadophorida [-ina] 
p.p ., Telostomata p.p ., Toxistomia p.p .) 
 Size, small to large; shape, variable, some species 
equipped with proboscis and a few species with 
non-suctorial tentacles; free-swimming; poorly 
developed alveoli; somatic ciliation, holotrichous, 
but reduced to girdles in some forms, and sparse in 
pleurostomes; somatic kinetid as for the class, but 
postciliary microtubules overlapping longitudinally; 
extrusomes as somatic mucocysts, clathrocysts, and 
lepidosomes, and oral and/or somatic toxicysts; oral 
region, typically anterior, with cytostome, apical or 
subapical, oval or slit-like, rarely permanently open, 
so that the cytopharynx becomes eversible in some 
species; oral dikinetids, rarely monokinetids, 
on border of cytostome-cytopharynx, typically 
with outer or posterior kinetosome bearing a 
slightly longer cilium and inner or anterior non-
ciliated kinetosome with a transverse microtu-
bular ribbon that extends anteriorly and then 
reflects posteriorly to support the cytopharynx; 
cytopharynx, supported by the rhabdos, which 
is formed by bulge microtubules and transverse 
microtubular ribbons and nematodesmata aris-
ing from oral dikinetids; toxicysts localized in 
or near the oral area, typically between the oral 
transverse ribbons and bulge microtubules of 
the rhabdos ; stomatogenesis, telokinetal; conjuga-
tion, temporary; rapacious carnivores of flagellates , 
ciliates, and other protists; two orders and one order 
incertae sedis . 
NOTE : Small and Lynn (1985), Foissner and 
Foissner (1988), Lipscomb and Riordan (1992), 
and Grain (1994) have suggested different ordinal, 
subordinal, and familial classifications for these 
ciliates. Recent molecular phylogenetic analysis 
17.3 The Ciliate Taxa to Genus 367
does not provide unambiguous support for any 
proposed taxonomy of haptorians (Strüder-Kypke, 
Wright, Foissner, Chatzinotas, & Lynn, 2006). 
Thus, until unambiguous, high-weight morpho-
logical synapomorphies are supported by molecu-
lar genetic evidence, we cannot support substantial 
subdivision and have remained conservative. 
 Order Haptorida Corliss, 1974 
 (syns. Acropisthiina p.p ., Belonophryina p.p ., 
 Didiniina p.p ., Dileptida p.p ., Enchelyina p.p ., 
 Helicoprorodontida p.p ., Helicoprorodontina 
p.p ., Inferotrichida p.p ., Lacrymariina p.p ., 
 Pseudoholophryida p.p ., Pseudoholophryina p.p ., 
 Spathidiida p.p ., Spathidiina p.p ., Trachelophyllina 
p.p .) 
 Somatic ciliation, holotrichous, but restricted to 
girdles in didiniids; oral region, typically circular 
or elliptical, surrounded by circumoral diki-
netids whose microtubules extend to support the 
cytostome-cytopharynx, but where circumoral 
dikinetids are absent, oralized somatic monoki-
netids bear nematodesmata for the rhabdos ; 14 
families. 
 Family ACROPISTHIIDAE Foissner & Foissner, 
1988
 (syn. Fuscheriidae ) 
 Size, small to medium; shape, ovoid to elongate; 
free-swimming; somatic ciliation, holotrichous, 
often more dense in the anterior half; brosse kine-
ties, 2–4; extrusomes as somatic mucocysts and oral 
toxicysts; oral region, apical, with oral dikinetids 
evenly surrounding cytostome, accompanied by 
some oralized somatic monokinetids ; oral nema-
todesmata arising from oral dikinetids and adja-
cent oralized somatic monokinetids; macronucleus, 
globular to ellipsoid, band-like or in many nodules; 
micronucleus, present; contractile vacuole, present; 
cytoproct (?); feeding on flagellates; in freshwater 
and terrestrial habitats; nine genera. 
 – Acropisthium Perty, 1852 
 – Actinorhabdos Foissner, 1984 
 – Chaenea Quennerstedt, 1867 
 – Clavoplites Foissner, Agatha, & Berger, 2002 *
 – Coriplites Foissner, 1988 
 – Dioplitophrya Foissner, Agatha, & Berger, 2002 *
 – Diplites Foissner, 1998 
 – Fuscheria Foissner, 1983 
 – Sikorops Foissner, 1999 
 Family ACTINOBOLINIDAE Kahl, 1930 
 (for Actinobolidae ; syn. Legendreidae ) 
 Size, small to medium; shape, ovoid; free-
swimming; somatic ciliation, holotrichous, with kine-
ties more or less spiralling; brosse kineties, at least 
two; extrusomes as somatic mucocysts and somatic 
toxicysts; retractable, non-suctorial tentacle-like 
processes, widely distributed over body, contain-
ing toxicysts, and associated with somatic monok-
inetids ; oral region, apical, with oral dikinetids 
surrounding apical cytostome; macronucleus, globu-
lar to ellipsoid to extremely elongate and ribbon-like; 
micronucleus, present; contractile vacuole, present; 
cytoproct (?);