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Webbia
Journal of Plant Taxonomy and Geography
ISSN: 0083-7792 (Print) 2169-4060 (Online) Journal homepage: https://www.tandfonline.com/loi/tweb20
Peculiarities of Chara filiformis (Charales,
Charophyceae) distribution and oospore sizes in
Lithuania
Zofija Sinkevičienė
To cite this article: Zofija Sinkevičienė (2019) Peculiarities of Chara�filiformis (Charales,
Charophyceae) distribution and oospore sizes in Lithuania, Webbia, 74:1, 133-138, DOI:
10.1080/00837792.2019.1607501
To link to this article: https://doi.org/10.1080/00837792.2019.1607501
Published online: 23 May 2019.
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ARTICLE
Peculiarities of Chara filiformis (Charales, Charophyceae) distribution and
oospore sizes in Lithuania
Zofija Sinkevičienė
Nature Research Centre, Institute of Botany, Vilnius, Lithuania
ABSTRACT
Distribution and ecological requirements of Chara filiformis A. Braun in Hertzsch in Lithuanian
water bodies were studied. This species has quite limited distribution in central and northern
Europe, clearly preferring the habitat ‘3140 Hard oligo-mesotrophic waters with benthic
vegetation of Chara spp.’. Morphological features of oospores and gyrogonites of C. filiformis
were studied based on 50 gyrogonites and 50 oospores taken from herbarium specimens
collected from Lake Germantas (55.979279, 22.14266 WGS) at the depth of 2–3 m on 17
August 2000. Largest polar axis (LPA, length), largest equatorial diameter (LED, width),
isopolarity index (ISI = LPA/LED × 100) and number of ridges were measured. The compara-
tive analysis revealed that the morphometry of oospores from the studied population
significantly differed from most of the data known from the literature.
ARTICLE HISTORY
Received 6 March 2019
Accepted 5 April 2019
KEYWORDS
Characeae; Chara filiformis;
distribution; gyrogonites;
oospores; morphometry
Introduction
Chara filiformis A. Braun in Hertzsch (1855) mor-
phologically strongly differs from other Chara species
by ‘threadlike’appearance due to very short or almost
rudimentary branchlets. The similar habit is charac-
teristic also of Chara kirghisorum Lessing which,
however, differs by being dioecious and having
mainly Middle Asian distribution with slight exit to
the edge of Eastern Europe (Romanov and Abdullin
2018). Monoecious C. filiformis, on the contrary, has
limited distribution in central and northern Europe.
It has been recorded in Belarus (Mikheyeva 2015),
Denmark (Baastrup-Spohr et al. 2013), Estonia (Torn
et al. 2015), France (Pyrenees) (Corillion 1957),
Germany (Teppke 2016), Latvia (Zviedre 2008),
Lithuania (Trainauskaitė1970; Kostkevičienėand
Sinkevičienė2008), Poland (Urbaniak and Gabka
2014), Russia (Pskov Oblast) (Hollerbach and
Krassavina 1983), southern Sweden (Blindow 2008;
Westling 2015) and Switzerland (Auderset Joye and
Schwarzer 2012). In most of the countries mentioned
C. filiformis is rare, threatened or even extinct. The
most recent locations have been recorded in north-
eastern? Germany, north-eastern? Poland, Lithuania
and Latvia. It seems that this species is still quite
widespread in these countries (Figure 1(a)).
In Lithuania, C. filiformis was first recorded at the
beginning of the nineteenth century as Chara funicularis
Pers. 1807 (Wolfgang 1822;Gorski1830). Later this
species was named Chara tyzenhausii (Gorski 1849). In
this way, count Konstantin Tyzenhauz, mainly known as
a famous ornithologist of the nineteenth century, was
honoured. He funded the preparation and publication of
the book on aquatic plants by Gorski in Berlin. This book
most probably has never been published and conse-
quently C.tyzenhausii remained only as an invalid
name (nomen invalidum). Galinis (1964,1968)knew
about the occurrence of a unique example of tables of
this issue (only pictures without description of plants) at
the Library of Polish Academy of Sciences in Krakow. In
1963, the Library of Lithuanian Academy of Sciences in
Vilnius received a microfilm of this publication from
Krakow. The picture in table 11 (Gorski 1849) is identical
to the imprint of the plant on the paper sheet of a
completely damaged authentic herbarium specimen by
Gorski, deposited at the Herbarium of Vilnius University
(WI). This drawing on table 11 of ‘Icones
Potamogetonum, Characearum, Cyperacearum et gra-
minearum novas vel minus cognitas species Lithuaniae
illustrantes’could be a type of C.tyzenhausii (if the name
were validly published). It was expected that authentic
specimens of this species would be found in Kiev, at the
National Herbarium of Ukraine (KW), however, the
envelope with macroalgae specimens from the historical
W. Besser collection was lost, most probably during the
Second World War. Most the specimens in the
Lithuanian Herbaria, collected in the twentieth century,
were named as C. jubata A. Braun.
From the beginning of the nineteenth to the
middle of the twentieth centuries, only scattered
locations of C. filiformis were recorded, mainly in
the environs of Vilnius (Wolfgang 1822;Gorski
1830;Mowszowicz1947). An extensive investiga-
tion of Characeae in the middle of the twentieth
century (Minkevičius 1954;Minkevičius and
CONTACT Zofija Sinkevičienėzofija.sinkeviciene@gamtc.lt
WEBBIA
2019, VOL. 74, NO. 1, 133–138
https://doi.org/10.1080/00837792.2019.1607501
© 2019 Dipartimento di Biologia, Università di Firenze
Published online 23 May 2019
Trainauskaitė1957;Šarkinienė1961; Trainauskaitė
1970;Šarkinienėand Trainauskaitė1973)revealed
species distribution in the Lakelands throughout
the country. The cited researchers were also the
main collectors of Characeae in 1950–1980. The
first doctoral dissertation on charophytes in
Lithuanian waters was prepared by Trainauskaitė
(1970).
Over the past three decades, a large amount of the
data on charophytes was collected during the inves-
tigations of water bodies in the protected areas, for
implementation of the Directives of the European
Union (Directive of Habitats and Water Framework
Directives). This material was used for the evaluation
of the current distribution of C. filiformis and its
ecological conditions in the habitats. The aim of this
work was to measure the size of generative fructifica-
tions (oospores and gyrogonites), because that has
never been performed on plants from Lithuanian
water bodies.
Materials and methods
The analysis of C. filiformis distribution in Lithuania
was based mainly on the revision of specimens
deposited at the Herbaria of the Institute of Botany
(BILAS) and Vilnius University (WI). Literature
data and those of personal investigations were also
used. The recent data (2013–2015) on species dis-
tribution were obtained from the Environmental
Protection Agency (AAA 2013–2015). The species
distribution was mapped by applying a grid system
of squares used at the Nature Research Centre,
Institute of Botany (Rašomavičius 2007). The data
on water physicochemical parameters of the moni-
tored lakes with C. filiformis were acquired from the
Environmental Protection Agency (AAA 2005–
2015).
For the investigation of fructifications, calcified oos-
pores were taken from the herbarium specimens of typi-
cal C. filiformis collected in Lake Germantas (55.979279,
22.14266 WGS) at the depth of 2–3 m on 17 August 2000.
To avoid mistakes, only the attached to the plant fructi-
fications were collected from different parts of the thallus,
choosing calcified and most likely mature oospores for
the measurements. Decalcification and preparation of
oospores was performed following the method described
by Holzhausen et al. (2015). Dry uncleaned gyrogonites
and wet (cleaned from calcification) oospores were mea-
sured using a NICON SMZ800 microscope with software
NIS –Elements D. Following Soulié-Märsche and García
(2015) for the morphometric analysis of gyrogonites and
oospores, the largest polar axis (LPA, length) and the
largest equatorial diameter (LED, width) were measured,
and the index of isopolarity (ISI = LPA/LED × 100) was
calculated. The number of ridges was examined also for
all 50 oospores and 50 gyrogonites.
Results and discussion
Distribution in Lithuania
Since the nineteenth century C. filiformis in Lithuania
has been recorded in 90 lakes and has never been
found in other types of water bodies. Over the last
century, C. filiformis has been recorded in 48 lakes,
whereas over the last two decades it has been recorded
in 68 lakes, of which 50 sites are new and in 18 lakes
the species has been recorded repeatedly. The map
shows the distribution of the species in the twentieth
and twenty-first centuries (Figure 1(b)). From the
beginning of the nineteenth century to about the
1940s, only four scattered locations (Wolfgang 1822;
Gorski 1830; Mowszowicz 1947) were known. These
points were totally covered by the points of subsequent
findings and are not presented in the distribution map.
The former and recent points of distribution show
evident concentration of the localities in the
Lakelands of the Baltic Highlands from the south-
west to the north-east of the country, where they con-
nect with localities in the south-east of Latvia (Zviedre
2008). Only one point indicates species occurrence in
the western part of Lithuania.
Ecological requirements
Chara filiformis is recorded mainly in the lakes with
average depth over 3 m and only solitary localities are
known in the shallowest lakes. Preferable depth range
is 1–4 m; however, it occurs also in the deepest and
the shallowest places. The maximal growing depth of
13 m was recorded in the last century (Šarkinienėand
Trainauskaitė1973), whereas recently it has not been
found deeper than 6 m. Basic physicochemical para-
meters of water (minimal, maximal ranges and aver-
age ± standard deviation), reflecting habitat
conditions of 57 monitored lakes with C. filiformis
are presented in Table 1.
Most of these lakes are attributed to the habitat
‘3140 Hard oligo-mesotrophic waters with benthic
vegetation of Chara spp.’and in many cases comply
with the requirements of good quality according to
the Water Framework Directive. The preference for
oligo-mesotrophic conditions is mentioned by many
authors (e.g. Zviedre 2008; Urbaniak and Gabka
2014; Teppke 2016).
Features of fructifications
Chara filiformis has a threadlike habit due to very short
branchlets (Figure 2(a)). It forms gametangia and sub-
sequently oospores or gyrogonites at the node of the
lowest corticated segment of branchlets. The gyrogo-
nites of C. filiformis examined in this study showed
quite large variation in shape (Figure 2(b)) from slightly
ovoid to long ellipsoidal. The gyrogonites with a much
134 Z. SINKEVIČIENĖ
wider upper and gradually narrowing lower part were
most unusual. Table 2 contains data on the gyrogonite
measurements performed on the basis of one popula-
tion from Lake Germantas. The length of gyrogonites
ranged from 750 to 920 µm, with an average of
844 ± 39.2 µm, whereas width range was 370–550 µm
(average 452 ± 39.5 µm). The ISI showed also quite large
variation from 149 to 228 (average 190 ± 17.3), which
confirms gyrogonite shape variation from quite broad
to elongated slender. The number of ridges ranged from
9 to 12, but often it was 10. We did not find any
publications about extant C. filiformis gyrogonite
dimensions for data comparison.
The morphological variation in oospores (Figure 2(c))
partly repeated that of gyrogonites, however, prolonged
slender oospores often were almost cylindrical. The oos-
pores with a gradually narrowing lower part were also
observed. The measurements of oospores revealed quite
wide variability in sizes (Table 2). The length ranged
from 680 to 810 µm, with an average of 753 ± 33.2 µm,
whenthewidthrangewas300–460 µm, at an average
753 ± 33.2 µm. The ISI varied widely within the range of
169–258, with an average of 209 ± 18.8, which exceeded
those of gyrogonites. This means that oospores were
relatively more prolonged and more slender than gyro-
gonites. The number of ridges was similar to that of
gyrogonites with 9–12 ridges on the oospore surface,
with an average of 10.2 ± 0.9, but often it was 11.
Comparing the results of our measurements with
the data known from the literature (Table 3), it can be
stated that they were significantly different. The mini-
mal length (680 µm) of the studied local population in
all cases exceeded the minimal length (500 µm)
recorded in many other European countries and was
close to their maximal values (680, 700 µm). The
maximal length of the examined oospores was more
than 200 µm bigger than that of the oospores recorded
by other authors. The minimal width (300 µm) of
oospores in the local population, on the contrary,
was less, whereas the maximal width (460 µm) was
close to other recorded maximal values, ranging from
386 to 450 (470) µm. The number of ridges on the
oospore surface was lower than in the cited literature.
The most often number of ridges (11) in our popula-
tion was mentioned as minimal by Wood and Imahori
(1965), Hollerbach and Krassavina (1983)andKrause
(1997), however, maximal ones (14) recorded in many
Figure 1. Distribution of Chara filiformis. (a) In Europe (filled contour of country indicates wide distribution; country code only
indicates limited distribution). (b) Distribution in Lithuania ( = localities in the twentieth century; = localities after 2000).
Table 1. Physicochemical parameters of water in the mon-
itored lakes with Chara filiformis in Lithuania (n= 57).
Parameters Minimum Mean ± SD Maximum
pH 8.1 8.5 ± 0.19 9.3
Secchi (m) 1.0 4.31 ± 1.7 7.48
Conductivity (µS/cm) 129 316 ± 59.8 508
Alkalinity (mgeq/l) 0.5 2.7 ± 0.6 4.2
O
2
(mg/l) 7.16 9.54 ± 0,82 11.23
Ca
2+
(mg/l) 24.8 45.5 ± 8.7 79.8
NH
4+
(N mg/l) 0.007 0.025 ± 0.03 0.135
NO
2
(N mg/l) 0.000 0.012 0.353
TN (mg/l) 0.245 0.663 ± 0.283 1.725
PO
43−
(P mg/l) 0.001 0.006 ± 0.002 0.020
TP (mg/l) 0.006 0.020 ± 0.007 0.067
WEBBIA: JOURNAL OF PLANT TAXONOMY AND GEOGRAPHY 135
other countries have never been estimated here. It may
be concluded that the oospores in the population from
Lake Germantas were longer, sometimes slightly nar-
rower (except for Polish data) and with a smaller
number of ridges. Comparing the size of oospores,
our data are closest to the data obtained in Poland
(Urbaniak and Gąbka 2014). Greater difference com-
pared to most of the former investigations could be
related to the conditions of measurement: wet or dry
oospores were measured, the number of oospores used
Figure 2. Morphology of Chara filiformis and their fructifications. (a) General view of C. filiformis from shallow water with nodal
bulbil. (b) Morphological variation of gyrogonites. (c) Morphological variation of oospores. (d) The difference between wet and
dry oospores colours.
Table 2. Features of dry gyrogonites and wet oospores of
Chara filiformis from Lake Germantas (n= 50).
Parameters Min–Max Mean ± SD
Gyrogonites LPA (µm) 750–920 844 ± 39.2
LED (µm) 370–550 452 ± 39.5
ISI 149–228 190 ± 17.3
No. of ridges 9–12 10.3 ± 0.8
Oospores LPA (µm) 680–810 753 ± 33.2
LED (µm) 300–460 363 ± 33.4
ISI 169–258 209 ± 18.8
No. of ridges 9–12 10.2 ± 0.9
LPA = largest polar axis (length); LED = largest equatorial diameter
(width); ISI = isopolarity index.
Table 3. Features of Chara filiformis oospores presented by different authors: minimal and maximal length, width and number of
ridges.
Authors LPA (µm) LED (µm) No. of ridges Colour
Migula (1897) 500–660 350–420 12–14 Dark brown to dark red brown
Corillion (1957) 500–600 350–420 12–14 Black
Wood and Imahori (1965) 600–660 390–420 11–12 Dark chestnut brown to almost black
Hollerbach and Krassavina (1983) 500–660 (680) 350–420 (472) 11–14 Dark chestnut brown to almost black
Krause (1997) 500–700 350–450 11–14 Dark chestnut brown to almost black
Urbaniak and Gąbka (2014) 510–705 305–385 –Black
This study 680–810 300–460 9–12 Dark brown (wet); almost black (dry)
LPA = largest polar axis (length); LED = largest equatorial diameter (width).
136 Z. SINKEVIČIENĖ
for examination, whether they were mature, in what
types of water bodies and how deep the plants grew,
etc. Moreover, significant difference in the results of
most recent measurements of the oospores of C. baueri
and the data known from the literature was noticed by
Pukacz et al. (2012). On the other hand, we examined
only one population from one lake.
In our study, we noticed the significant difference
in coloration of dry and wet oospores. The wet oos-
pores were red brown and dry ones were almost black
(Figure 2(d); Table 3). According to various authors,
the colour of C. filiformis oospores is characterised as
dark brown, dark red brown, dark chestnut brown to
almost black or black (Table 3). Possibly, the oospore
colour is related to the observation conditions or its
maturity. These conditions were not specified in the
literature cited.
The study of fructifications in one population is
the first step, but it is insufficient to answer all the
questions concerning the sizes and other features of
oospores and gyrogonites, therefore, a more extensive
study is needed to obtain more precise data on the
morphometry of fructification of C. filiformis
throughout its distribution area.
Acknowledgements
I would like to thank Vita Monkuvienėand Zigmantas
Gudžinskas (Nature Research Centre, Institute of Botany)
for compiling the distribution maps and preparation of
illustrations. I am grateful to Violeta Ptašekienėfor linguis-
tic help. I also acknowledge the Environmental Protection
Agency for the data on monitoring of the water bodies.
Disclosure statement
No potential conflict of interest was reported by the author.
ORCID
Zofija Sinkevičienėhttp://orcid.org/0000-0003-2163-
9922
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