Morphology, Infraciliature and Ecology of a New Planktonic Ciliate

E u r o p .J . P r o t i s t o l3. 1 , 3 8 9 - 3 9 5 ( 1 9 9 5 )
D e c e m b eIr5 , 1 , 9 9 5
European Journal of
PROTISTOLOGY
Morphology,Infraciliature
and Ecologyof a New
PlanktonicCiliate,Histiobalantium
bodamicum
n. sp. (Scuticociliatida:
Histiobalantiidae)
Karl-HeinzKrainer
"Biolab Tullnerfeld", Laboratory for Applied Ecology, Königstetten, Austria
HelgaMüller
Universityof Konstanz,Limnologicallnstitute,Konstanz,Germany
SUMMARY
Histiobalantium bodamicum was first found in the pelagic zone of Lake Constance, Germany. Subsequendy further populations have been discovered in two dredged groundwater ponds in Styria and Carinthia (Austria). Its morphology and infraciliature were
studied in live cells and in specimensimpregnated with protargol. Histiobalantium bodamicum measures40-60 x 35-45 pm, has usually a long-ellipsoid macronucleus,accompanied by several globular to lenticular micronuclei, and three contractile
vacuoles. Somatic ciliation is interspersed with long tactile cilia. The huge buccal cavity
contains a prominent, roughly inverted 3-shaped paroral kinety and three adoral membranelles M 1, M2, M 3 arranged closely and in parallel at the paroral's anterior end. The
posterior segment of the paroral kinety is accompanied in close distance by a single-filed
kinety (scutico-vestige).The adoral membranelles and the paroral kinety form an obruse
angle. Membranelle 3 is composed of a single row of monokinetids. Abundance, seasonal
population dynamics and vertical distribution of H. bodamicum in two Austrian dredged
groundwater ponds and in Lake Constance are described. A synopsis of morphological
and ecological data of the presently known speciesof the family Histiobalantiidae is Compiled.
Introduction
With the taxon described here, 5 speciesare presently
assignedto the genus HistiobalantiumStokes. The family Histiobalantiidae De Puytorac & Corliss 1979 is
monotypic and is defined by a huge buccal cavity, containing a lengthy paroral kinety composed of dikinetids
and three adoral membranellesM1, M2, M3, plus a
scutico-vestige[3]. Four speciesare facultatively psammophilic both in freshwater and marine habitats [6.
1,71-.The new species described here is characterizäd
by having membranelle 3 located closely and in parallel
to the two other membranelles M 1 and M 2. and bv its
planktonic habitat.
@ 1,995 by Gustav Fischer Verlag, Stuttgart
Material
and Methods
All morphological investigations were carried our on a
non-axenic stock culture of H. bodamicum originally isolated
from "Überlinger See", the northwestern pari of Lake Constance (E9'10'; N47"45'). Ecological data were obtained
from field samples from Lake Constance and from two Austrian groundwäter ponds. Lake Constance is a deep, meso-eutrophic, prealpine lake. Sampling, counting, and culturing o{
H. bodamicum from Lake Constance is described in detail by
'l7eisse
Müller &
[15]. The "Schwarzl-Badesee" is a mesotrophic dredged groundwater pond of about 0.08 km2,
around 6 m deep, and situated closely south of Graz, Styria,
Austria (E 15"30'; N46'50'). The "rü/eizelsdorferTeich" is an
oligotrophic dredged groundwater pond of about 0.07 km2,
0932-4739-9
5-003
1-0389S3.50-0
390 . K.-H. Krainerand H. Müller
around 8 m deep,situated30 km south of Klagenfurt,Carinthia, Austria (E1,4",20'; N46', 30'). The samplesfrom
the groundwater ponds were collectedfrom March 1992
through February 1,993.To estimatethe number of individuals in the dredgedgroundwaterponds, subsampleswere
fixed in HgCl2after Stieve[16] and allowedto sedimentovernight. Countswere performedon microscopeslidesat 100fold magnification.All staining and morphometric proceduresfollowed the methodsdescribedin Foissner[8].
Results
Histiobalantiwm bodamicum n. sp.
Diagnosis.In vivo about 40-60 x 35-45 pm sized
Histiobalantium with somatic tactile cilia and three
contractile vacuoles. Macronucleus ellipsoid, several
micronuclei. Buccal cavity with roughly inverted 3shaped paroral kinety and three adoral membranelles
arranged closely and in parallel. Adoral membranelles
and paroral kinety form an obtuse angle. Pelagic in
freshwater lakes.
Type location. Northwestern part ("Ueberlinger
See") of Bodensee (Lake Constance, Germany;
E9"10':N47'45').
Deriuatio nominis. "Lacus bodamicus" (latin) for
Bodensee(Lake Constance).
Type specimens. A holotype and a paratype of
H. bodamicum as two slides of protargol impregnated
cells have been deposited in the collection of microscope slides of the Oberösterreichisches Landesmuseum in Linz (LI), Austria.
Morphology (Figs. 1-15; Table 1). Body variable in
outline, usually ovoid, otherwise globular or elliptical,
sometimes lemon-shaped. Dorsal side hemispherical,
ventral side flat. Huge buccal cavity occupying ventral
surface, outline in transverse section hemispherical to
trapezoid (Fig.6). Buccal cavity opens at surface in a
longitudinal cleft, highly variable in width, contains
prominent sail-like, hyaline paroral membrane (undulating membrane) and stiff, slowly moving adoral membranelles with 30 pm long cilia (Figs. 9, 12). Oral striae
(cp. Dragesco [5]) weakly rccognizable only in living
cells (arrows in Fig. 1 ). Macronucleus usually in left cell
half near anterior end; in vivo long-elliptical and
smooth in outline, in protargol impregnated specimens
globular to cucumber-shaped, often with indentations
and tapered ends; contains many globular to elliptical
nucleoli of various size. Four to eight globular to lenticular micronuclei, closely attached to macronucleus
usually at its dorsal side; in vivo hardly recognizable,
only weakly stained by protargol. Three contractile vacuoles at dorsal side of cell, two subterminally at right
anterior and posterior end, respectively and one at left
side near posterior end of macronucleus; excretory
pores not observed. Extrusomes sickle-shaped, about
3-4 pm long, distributed in variable number beneath
cell surface; distinctly stained by protargol (Fig. 1a).
Extruded organelles not observed. Cytoplasm of starving specimenscolourless, well-fed specimenswith yellow-greenish inclusions, 2-3 1tm in diameter, and
bluegreen inclusions, 1,-2 pm in diameter. Feedson algae and, probablg bacteria; grows well if fed with the
cryptomonadRbodomonas sp. [15]. Food is ingestedin
Table 1. Morphometric characteristicsfrom Histiobalantium bodamicum (type population cultured in \7C medium according
to Guillard & Lorenzen [10] on a diet of Rhodomonas sp.)
SD
Character"
Cell, length
Cell, width
Macronucleus, length
Macronucleus, width
Micronuclei, number
Micronucleus, diameter
Buccal cavitS length
Buccal cavity, width
Membranelle 2, length
Somatic kineties, number
48.6
36.1
2r.7
8.5
4.6
2.0
39.0
16.1
10.5
73.5
5.8
4.9
1..9
1,.4
1.9
0,0
4.8
J.a
2.0
2.6
5(lx
CV
Min
Max
J+.2
1.1..9
42
30
20
7
3
2
30
fl
55
37.5
25
tI
8
2
46
2l
1.3
77
24.4
3.8
2.0
3.6
0.0
23.1
rt.4
4.0
6.9
IJ.O
8.7
16.5
41.3
0.0
12.3
21.t
1.9.0
3.6
t)
70
10
10
10
10
10
10
10
10
10
10
" Data based on randomly selected,protargol impregnated and mounted specimens.Measurements in pm. Abbreviations: CV
= coefficient of variation in "Ä, Max = maximum, Min = minimürl, n = number of investigated specimens,SD = standard
deviation, Sd* = standard deviation of the mean, * = arithmetic mean.
Fig. 1-5. Interphasic morphology of Histiobalantium bodamicum n. sp. (Fig. 1, 1 a, from life; Figs. 2- 5, protargol impregnation). - Fig. 1. Ventral view. Arrows mark oral striae. - Fig. 1a. Extrusome. -Fig.2.Infraciliature
of dorsal side. Arrows
mark distinct widening of two kineties at posterior end (cytopyge?). - Fig.3. Posterior polar view of infraciliature. - Fig.4
Infraciliature of ventral side. - Fig. 5. Anterior polar view of infraciliature. Bars = 10 pm. CY = cy16s1o-e; L = weakly stained
line surrounding buccal cavity; }l4t,2,3 = adoral membranelles; MA = macronucleus; PK = paroral kinety; $\/ = posterior
kinety regarded as scutico-vestige.
Morphology of Histiobalantiumbodamicumn. sp. . 391
lfl2
J||3
MA
392 ' K.-H. Krainer and H. Müller
$*
tt
Morphology of Histiobalantiumbodamicumn. sp. . 393
o
..o
o-10 10-50 50-100 1oo-5o cells./l
aa
oo
I
t
'o
2
a
rO
'.o
oO
oa
'.o
oo
e
g4
oC)
ill
\_-/
IV V
VI vtl vill IX X X I xll
tl
Fig. 16. Abundance(expressed
as cells/l)and seasonalpopulation dynamicsof Histiobalantiumbodamicumn. sp.in two
dredged groundwater ponds in Austria (solid circles =
Teich";
"Schwarzl-Badesee",
open circles = "'Weizelsdorfer
seemap at top right of figure).
toto by the huge buccal cavity; prior to ingesting, food
cells causea lightning reaction of the ciliate when touching the tactile cilia. Movement floating with extended
tactile and somatic cilia, interrupted by sudden, short
jumps.
Somaticcilia 11-13 pm long, narrowly spaced,interspersedwith 25 - 35 pm long, stiff tactile cilia (bristles),
origin of which not recognizable in the infraciliary pattern of kinetids. About 70 kineties, composed of 50 - 60
monokinetids, abut at acute angles preorally, and extend posteriad in longitudinal, dense rows. Monokinetids at both poles loosely spaced.At dorsal side kineties
show conspicuous widenings at various places (cytop y g e ? ;F i g s . 2 , 1 3 ) .
Paroral kinety at right of buccal cavity, usually divided in two C-shaped segments,as a whole appearing
as inverted 3-line; commences anteriorly at right end of
adoral membranelleM 1, coursesposteriad along right
wall of buccal cavitS in mid-region of cavity or just
posterior slightly to distinctly curved out leftward
("hook"). Posteriormostpart coursesanteriad, increasing gradually in thickness. Posterior segment accompanied by a kinety of tightly spaced basal bodies, at
"hook" and just posterior very near to paroral membrane, then increasing gradually in distance, forming
a "thickened" posterior termination (scutico-vestige,
cf. Discussion;Figs. 3,4,10,11). Buccal cavity entirely
surrounded by wavy, weakly stained line, very likely
the actual buccal opening (Fig. a). Adoral membranelles spacedclosely and in parallel in transversedirection at anterior end of buccal cavity form an angle of
approximately 1.30-1.40' with paroral kinety. Anteriormost M 1 straight, composed of two tighdy packed
rows of ciliated kinetosomes, M 2 composed of about
8-10 of kineties, posteriormost M3 a single, straight
row of packed kinetosomes. No data available on resti n g c y s f sa n d c o n j u g a t i o n .
Occurrence and Ecology (Fig. 16, Table 2)
As yet found at type location and in two oligo- to
mesotrophic dredged groundwater ponds (cf. Material
and Methods). In Lake Constance, H. bodamicum was
regularly observed s.ince1987 at the site of maximum
depth (147 m) of "Uberlinger See", the northwestern
part of the lake 113, 141. The vertical distribution o{
Table 2. Vertical distribution (cells per liter) of Histiobalantium bodamicum in Lake Constance on five occasions in 1989
(- = below detection limits)
Depth
Date:
18 April
0-8 m
8-20 m
30m
40m
50m
75m
1 0 0m
140
80
280
200
2 May
20 June
80
)+o
80
:' o
25 July
19 Sept.
580
1340
40
1240
2040
-_200
80
Fig. 6-15. Light micrographs of Histiobalantium bodamicum n. sp. (Figs. 6-9, from life, interference contrast; Figs. 10-15,
protargol impregnation). - Figs. 6,T.lnterphasic specimensat transverse focus level showing huge buccal cavity, long tactile
cilia (arrows), sail-like, hyaline paroral membrane and ellipsoid macronucleus. - Fig. 8. Specimen focused to the plane where
sickle-shapedextrusomes are recognizable(arrow). - Fig. 9. Specimenat transversefocus level showing stiff cilia deriving from
the membranelles (arrow). - Figs. 10, 11. Infraciliature of ventral side focused at two different planes. Arrows mark closely
accompanying posterior kinety (scutico-vestige?).-Fig. t2.Infraciliature of ventral side focused to plane where the stiff cilia of
the membranelles are recognizable (arrows). - Fig. 13. Infraciliature of dorsal side showing distinct widening of somatic kineties at posterior end (arrows). -Fig. 14. Specimen focused to plane where protargol-affine rods (extrusomes?)are recognizable. - Fig. 15. Specimen focused to plane where macronucleus is recognizable. Bars = 10 pm.
394 . K.-H. Krainer and H. Müller
Table 3. Compilation of morphological characters and habitats of previously described speciesof Histiobalantium Stokes.
Dash means no data
Species
Cell,
length
(pm)
Tactile
cilia
(bristles)
Contr.
vac.
Macronucleus
Micronuclei
number
Biotopes, records
Author
malus
1 3 5- 1 5 0
yes
multiple
2 parts
1l
freswater,sediment (vicinity of
Hamburg, Außenalster, FRG,
= locus classicus)
[ 11 ]
1 3 0- 2 5 0
yes
multiple
2 parts
2-t0
freshwater sediment s (Etang
de Cazeaux, France; Yaounde,
Camerun)
[5, 6l
2 parts
variable
number
freshwater sediments (puddles,
ditches in region of ClermontFerrand, France)
tel
single
2 pats
9
microbenthos, low salinity
lagoons of Caspian Sea
(Azerbaijan)
U,2l
multiple
2 parts
1.-2
freshwater sediments(vicinity
of Hamburg, FRG)
t 11 l
2 parts
3-7
freshwater sediments
(Fontainebleau, France;
Cotonou, Benin)
16,71
marine sediments (Kiel Bight,
FRG = locus classicus)
[12]
150-230
100
70-95
yes
5 5 * 1 0 5 yes
marrnum
mtnor
8 0- 1 6 0
yes
single
2 parts
75-1"00 yes
single
2 parts
1-3
marine sediments (Roscoff,
France)
t4l
60-1.02 yes
multiple
(five)
single
2
freshwater sediment (Lake
Ontario at Burlington,
Canada)
l17l
40-55
3-4
single
z
freshwater sediments (Lake
Ontario at Burlington,
Canada)
[171
3
single
4-9
freshwater, pelagic zone
(Lake Constance, FRG;
dredged groundwater
ponds, Austria)
this study
bodamicum 40-50
yes
H. bodamicwmatthis stationwas investigatedon 5 occasionsin 1989 (Table2). Numbers exceeding1000
cells/l were recorded in the uppermost 20 m of the
water column in summerand autumn. In contrast'cell
concentrationsin 100 m depth were below detection
limits. Maximum abundanceof 6,400cells/literwasrecorded in the 0-8 m depth interval on the 4th of July
1989. For further ecolofical data on H. bodamicumof
the locus classicuspopulation see detailed study by
Müller & S(eisse[15].
The seasonaldynamicsof the populationsin the Styrand the Carinthian "'$Teizelsian "Schwarzl-Badesee"
dorfer Teich" are shown in Fig. 16. The species
appearedin low numbers(10-320 cells/l)throughout
the year (exceptJune,August and September)in both
ponds.Maximä were observedin May L992(240 cellsll
in "s7eizelsdorferTeich") and in February 1'993(320
cells/l in "schwarzl Badesee"),near the bottom of
the ponds (in 7 m depth and 5 m depth, respectively).
Discussion
Histiobalantiwm bodamicwm has the typical characteristics of the family Histiobalantiidae as defined by
Corliss [3], i.e. a conspicuousbuccal cavity containing
a prominent paroral kinety and three adoral membranelles, representing the tetrahymenal organization.
However, it differs in the compositon of the posterior
termination of the paroral kinety (or segment C,
regarded as scutico-vestige; [9]). In H. natans and
H. maius, the scutico-vestigeconsists of a lengthy field
of four rows of kineties [5 , 7 , 9]. However, in H. boda.micum a scutico-vestige is not clearly obvious.
Possibly, the single-filed kinety which accompanies
the posterior segment of the paroral kinety is a scutico-vestige(Figs. 3, 4). The origin of this kinety has been
followed during stomatogenesis:In some later stages,
distinct scutico-fields appear at the terminations of
the newly developing paroral kineties. In very late
Morphology of Histiobalantiumbodamicumn. sp. . 395
2 AgamahevF. G. (1983):The ciliatesof the CaspianSea.
Leningrad(in Russianwith Englishsummary).
3 CorlissJ. O. (t9791:The ciliatedprotozoa.Characterization, classificationand guideto the literature.2nd ed.PerBamonPress,Oxford, New York.
4 DragescoJ. $9601 Cili6s m6sopsammiques
littoraux.
Syst6matique,
morphologie,6cologie.Trav.Stn.biol. Roscoff,122,1-356.
5 DragescoJ. $968): Les genresPleuronemaDujardin,
Schizocalyptranov. gen. et Histiobalantium Stokes(CiIi6s HolotrichesHym6nostomes).Protistologica,4, 85t06.
5 DragescoJ. et Dragesco-Kern6is
A. (1986):Cili6slibresde
I'Afrique intertropicale.Introductionä la connaissance
et
ä l'6tude descili6s.Faunetropicale,26, "1.-559.
7 Dragesc<iJ. et Iftode F. (1972\ Histiobalantium natans
(Clap. & Lachm., 1858): morphologie, infraciliature,
morphogenöse(holotricheHymenostomatida).Protistologica,8,'W.
347-352.
8 Foissner (1991,):Basiclight and scanningelectronmicroscopicmethodsfor taxonomicstudiesof ciliatedprotozoa.Europ.J. Protistol.,27,313-330.
9 GroliöreC-A. (1973):Descriptionde quelquesespöces
de
cili6s hymenostomesdes genres Satbrophilus Corliss,
'1.786,
t960, Cyclidium O. F. Mueller,
Histiobalantium
Stokes,1886.J. Protozool.,20,369-376.
10 Guillard R. R. L. and LorenzenC.1.0.972): Yellow-green
algae with chlorophyllide C. J. Phycol., 8, 10-'J.4.
11 Kahl A. (t93L): UrtiereoderProtozoaI: I7impertiereoder
Ciliata (Infusoria).2. Holotricha außerden im 1. Teil behandeltenProstomata.
TierweltDt1, 21, 181-398.
12 Kahl A. (1935):UrtiereoderProtozoaI: \Timpertiereoder
Acknowledgements
Ciliata (Infusoria).4. Peritrichaund Chonotricha.Tierwelt
Dtl., 30, 651-886.
'Sfe
wish to thank Prof. Dr. D. G. Müller, Konstanz,who 13 Müller H. (1989): The relative importanceof different
provided laboratory facilitieswhere H. bodamicwmcultures
ciliate taxa in the pelagicfood web of Lake Consrance.
'We
could be maintainedfor more than two years.
also reMicrob. Ecol.,18, 261-273.
ceived support from "Deutsche Forschungsgemeinschaft"14 Müller
H., SchöneA., Pinto-CoelhoR. M., SchweizerA.,
'Weisse
within SFB248 "Cvclins.of Matter in Lake Constance".
and
T. (1991): Seasonalsuccession
of ciliatesin
Lake Constance.Microb. Ecol., 21, 1t9-138.
15 Müller H. and WeisseT. (1994):Laboratoryand field observationson the scuticociliateHistiobalantium from the
pelagiczoneof Lake Constance,FRG. J. PlanktonRes.,
References
16,39r-401.
16 RomeisB. (1967):MikroskopischeTechnik.Oldenburg,
München.
1 AgamalievF.G. (1972):Ciliatesfrom microbenthosof the
islandsof Apseronskijand Bakinskijarchipelagosof the 17 Wilbert N. (1986): Ciliaten aus dem Interstitialdes Ontario Sees.Acta Protozool.25. 379-396.
CaspianSea.Acta Protozool.,10, 1,-27.
stages, remnants of these scutico-fields remain intact.
'We
assumethat these remnants are the origin of the single-filed kinety.
The most important infraciliary feature of H. bodamicum is the spatial relation of the adoral membranelles to each other and to the paroral kinety. In
contrast to H. bodamicum. alI other known species
have membranelles M 1 and M 2 in an acute angle to
the paroral kinety, and their M 3 is located roughly
at right-angles to M 2, thus forming a more or less distinct triangle 15,7, 9, 171.Histiob alantiwm bodamicum
is the first member of the genus having adoral membranelle M 3 shifted closely and in parallel to the two
others, and in which the adoral membranelles form
an obtuse angle with the paroral kinety. From this point
of view, H. bodamicumiswell separatedfrom the other
species.However, only considering the in vivo-aspects,
the new species is very similar to H. natans and
H. minor with respect to size, number of contractile
vacuoles and freshwater habitat. It can only be differentiated by the nuclear apparatusand presence/absence
of tactile cilia. Table 3 lists the most important morphological characters and the habitats of the Histiobalantium-species described to date. Up to now,
H. bodamicum is the only planktonic species of the
genus H isti o b alantium.
Key words: Histiobalantium bodamicumn. sp. - Morphology - Infraciliature- Ecology
Karl-HeinzKrainer,Wienerstrasse
45, A-3433Königstetten,
Austria