The Impact of Environmental Factors on Diversity of Ostracoda in Freshwater Habitats of Subarctic and Temperate Europe

Abstract

Iglikowska, A. & Namiotko, T. 2012: The impact of environmental factors on diversity of Ostracoda in freshwater habitats of subarctic and temperate Europe. — Ann. Zool. Fennici 49: 193–218. In this study, we compared the ostracod species diversity in selected inland-water habi-tats of Lapland and Poland, and assessed the relationships between ostracod occur-rence and abiotic environmental variables. In total, 41 species were collected, of which only 15 species were found in Lapland, as compared with 35 in Poland. Almost all spe-cies collected from the Lapland sites were eurybiontic and no clear differences were found between ostracod assemblages inhabiting different habitat types. We hypoth-esize that this homogeneity might be a consequence of the raised water level during the springtime snow melt, temporarily connecting various waterbodies. The main factors limiting distribution of ostracod species in Lapland appeared to be low pH and low ionic content of water. In Poland, predominantly stenobiontic species were observed. In temporary waters and peat-bogs of this area useful indicator species were identified.

Full text

Ann. Zool. Fennici  
 




Institute of Oceanology, Polish Academy of Sciences, Department of Marine Ecology, ul.
Powstańców Warszawy 55, PL-81-712 Sopot, Poland (corresponding author’s e-mail: iglikowska@
iopan.gda.pl)
Laboratory of Limnozoology, Department of Genetics, University of Gdańsk, ul. Kładki 24,
PL-80-822 Gdańsk, Poland
Received 3 Aug. 2011, nal version received 15 Feb. 2012, accepted 22 Mar. 2012

Ann. Zool. Fennici
In this study, we compared the ostracod species diversity in selected inland-water habi-
tats of Lapland and Poland, and assessed the relationships between ostracod occur-
rence and abiotic environmental variables. In total, 41 species were collected, of which
only 15 species were found in Lapland, as compared with 35 in Poland. Almost all spe-
cies collected from the Lapland sites were eurybiontic and no clear differences were
found between ostracod assemblages inhabiting different habitat types. We hypoth-
esize that this homogeneity might be a consequence of the raised water level during the
springtime snow melt, temporarily connecting various waterbodies. The main factors
limiting distribution of ostracod species in Lapland appeared to be low pH and low
ionic content of water. In Poland, predominantly stenobiontic species were observed.
In temporary waters and peat-bogs of this area useful indicator species were identied.
Introduction
Ostracods are tiny ubiquitous arthropods, occur-
ring in all marine and non-marine aquatic habi-
tats, and are even found in some terrestrial
habitats such as humid forest soils (Horne et al.
2002). Nowadays, there are about 8000 ostra-
cod species globally, of which slightly more
than 2000 are freshwater species belonging to
three superfamilies: Darwinuloidea, Cypridoidea
and Cytheroidea (Martens et al. 2008). In the
whole Palaearctic, the region with the highest
ostracod specic diversity, there are 87 known
genera with about 700 freshwater species (Mar-
tens et al. 2008), but even within Europe there
are areas where the ostracod fauna has been
less well explored, as e.g. northern Fennoscan-
dia (Iglikowska & Namiotko 2010). The Polish
ostracod fauna is faunistically better known,
but our knowledge of ecology and relationships
with environment is still inadequate, with only
a single paper published on this topic to date (by
Martins et al. 2009).
Ostracods are used as indicators of particular
characteristics of aquatic habitats: many species
have different, specic tolerance ranges and pref-
erences within the full spectrum of environmen-
tal factors (see e.g. reviews in Holmes & Chivas

 Iglikowska & Namiotko   
2002, Park & Smith 2003). The development
of multivariate methods in ecology in the last
decades of the 20th century has helped to reveal
species–environment relationships. In Europe,
recent papers using such methods have reported
on relationships between freshwater ostracods
and environmental factors in France (e.g. Mar-
monier et al. 2000), Germany (e.g. Viehberg
2006), Hungary (Kiss 2007), Italy (e.g. Pieri et
al. 2009), Luxembourg (Gerecke et al. 2005),
Poland (Martins et al. 2009), Portugal (Martins
et al. 2010), Serbia (Karan-Žnidaršič & Petrov,
2007) and Spain (e.g. Poquet & Mesquita-Joanes
2011). However, data on the assemblages occur-
ring in northern and temperate Europe are still
lacking.
The main goals of this study were (1) to
conduct faunistic surveys of ostracod assem-
blages in three types of freshwater habitats: tem-
porary waters, peat-bogs and shallow riparian
water of lakes in two geographically and physi-
ographically different regions, northern subar-
ctic Europe (Norwegian and Finnish Lapland)
and central temperate Europe (Poland); (2) to
compare ostracod species diversity and richness
among these habitats and regions; (3) to perform
zoocoenological analysis in an attempt to distin-
guish ostracod assemblage types characteristic
and indicative of the studied habitats, (4) to
investigate relationships between the occurrence
of particular ostracod species and abiotic envi-
ronmental factors, and (5) to assess usefulness of
ostracods as indicators of environmental condi-
tions in freshwater habitats.
Study areas and regional settings
Our studies were focused on two physiographi-
cally and climatically different European regions,
latitudinally ca. 2000 km apart: one in north-
ern subarctic Europe, namely Lapland (66°28´–
69°20´N, 15°24´–27°54´E), and the other in cen-
tral temperate Europe, Poland (50°28´–54°27´N,
15°36’–23°24´E). In this paper, the term “Lap-
land” is applied to the regions of Norwegian and
Finnish Lapland.
Climatic conditions in Lapland are inuenced
by two opposing factors. The maritime zone is
strongly inuenced especially in winter by air
masses warmed by the northward ow of the
North Atlantic Drift (Gulfstream). This amelio-
rating inuence is countered by the strong cool-
ing effect of arctic and continental air masses
from Eurasia. The Scandinavian Mountains play
a major role in shaping climate of the Fennos-
candia by blocking the warm Atlantic air masses
(Tikkanen 2005). Annual air temperature range
is about 10 °C along the west coast of Norway,
but it is a more extreme (29 °C) in the Finnmark
region (to the east of the Scandinavian Moun-
tains) and 26–28 °C in NE Finland. The Scandi-
navian Mountains are the major factor, so on the
western slopes annual precipitation amounts to
about 4000 mm near Bodø in Norway, whereas
in the rain shadow to the east decreases abruptly
to < 400 mm in Finnmark and Finish Lapland.
In the east part of Lapland snow cover persists
for more than six month (Pulkkinen & Rissanen,
1997, Stebel et al. 2007).
In Poland, climatic conditions are shaped
predominantly by location, and its continental
climate is modied latitudinally by the increase
in altitudes from the lowlands of northern Poland
to high altitudes of the Carpathian Mountains
in the south. The coldest month is usually Janu-
ary, when mean temperatures range from about
–1 °C near Szczecin in NW Poland to –8 °C
in the Tatra Mountains in the south. The mean
temperature in July, the warmest month, is 17 °C
along the north coast of Poland but 19 °C in
the south and east. The amount of precipita-
tion depends largely on altitude: in the wettest
regions of the Carpathian Mountains and the
uplands of southern Poland, rainfall ranges from
1000 to 1700 mm per year, but in the lowlands
the rain-shadow effect restricts precipitation to
< 500 mm per year (Martyn 1995).
Material and methods
Ostracod samples and environmental data were
collected at 49 stations: 24 in Lapland (L1–L24)
and 25 in Poland (P1–P25) (Fig. 1). Of the 24
sites in Lapland, all sampled in July 2006, 7
were in northern Norway, while the remaining
17 were in four provinces of Finland. In Poland,
samples were collected from 25 sites scattered
over the whole country (Fig. 1 and Table 1).

   Ostracods ecology of subarctic and temperate Europe 
Fig. 1. 
Sampling sites were selected to represent
three types of freshwater habitat: (1) temporary
waters (eight sites in Lapland and eleven sites
in Poland), (2) peat-bogs (eight and seven sites,
respectively), and (3) shallow riparian water of
lakes (eight and seven sites, respectively). Ostra-
cod samples were collected using a hand-net
(120 µm mesh size) from the bottom surface of
1 m2 at depths to max. ~60 cm (i.e. arm’s reach).
Samples were preserved in the eld in 75% etha-
nol, and later in the laboratory washed with tap
water through a 120 µm sieve and preserved in

 Iglikowska & Namiotko   
Table 1.        
et al




      
      
Lapland
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
Poland
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       
       

   Ostracods ecology of subarctic and temperate Europe 
95% ethanol. Ostracods were identied under a
microscope using both valve and soft body char-
acteristics using the keys of Sywula (1974) and
Meisch (2000).
A suite of physical and chemical variables
(Appendices 1 and 2) were measured at each site.
Water temperature, dissolved oxygen content,
salinity, conductivity and pH were measured in
situ using a hand-held multi-parameter instru-
ment (WTW Multi 350i). Phosphate, nitrate, iron
and calcium ions in the water were measured
using colorimetric tests. A Secchi disc was used
to assess water transparency. Sediment proper-
ties, like organic matter and water content, were
assessed back in the laboratory using the stand-
ard procedure of Håkanson and Jansson (2002).
In the faunistic and community analyses,
only samples containing > 30 indiv. m–2 were
considered. Relationships between ostracod site
assemblages were examined using UPGMA
(Unweighted Pair Group Method with Arith-
metic mean) hierarchical clustering based on
square-root transformed species abundances per
square meter and the Bray-Curtis similarity coef-
cient. A “similarity prole” (SIMPROF) per-
mutation method (with 999 simulations) was
implemented with the UPGMA procedure to test
the null hypothesis that samples in a given clus-
ter (representing a group of similar site assem-
blages) do not differ from each other in their
multivariate structure (Clarke & Warwick 2001,
Clarke & Gorley 2006). Additionally, after the
cluster analysis, individual species contributions
to the observed clustering pattern were examined
using “similarity percentages” (SIMPER), a pro-
cedure that allows assessment of which species
are principally responsible for the separation of
the sets of samples (assemblage types) (Clarke &
Warwick 2001, Clarke & Gorley 2006).
The analysis of similarities (ANOSIM), a
non-parametric permutation test (Clarke & War-
wick 2001), was used to investigate associations
between the site assemblage structure and both
the study region, and the type of habitat within
the region. For ANOSIM, sampling sites were a
priori grouped according to two criteria: (1) the
region (two groups: Lapland and Poland), and
(2) the habitat type within the region (six groups:
peat-bogs in Lapland (LP), peat-bogs in Poland
(PP), shallow riparian water of lakes in Lapland
(LSL), shallow riparian water of lakes in Poland
(PSL), temporary waters in Lapland (LTW) and
temporary waters in Poland (PTW). Each time
1000 random or actual (if < 1000) number of
permutations was used to obtain r values and
probability levels.
To detect the main patterns and gradients of
diversity in particular environmental variables
and to assess how the sampling sites differed
from each other in abiotic conditions, an uncon-
strained ordination of the Principal Components
Analysis (PCA) was used on the basis of the
Euclidean distance matrix, calculated from the
standardised values of the studied environmental
variables. ANOSIM was also employed in this
analysis (Clarke & Warwick 2001).
To explain and describe the relationships
between the ostracod species/assemblages and
the environmental factors, two methods were
employed: Canonical Correspondence Analy-
sis (CCA), a method of constrained ordination
detecting main patterns of dependence between
two datasets of variables (ter Braak & Šmilauer
2002), and BEST, which analyses every possible
combination of variables within the two matri-
ces (environmental and faunal). BEST detects
a subset of environmental variables which best
explains the samples ordination based on the
faunal matrix (for details see Clarke & Warwick
2001 and Clarke & Gorley 2006).
Finally, biodiversity of site assemblages was
estimated using both the standard measure of
the Shannon-Wiener diversity index (H´), and
the average taxonomic distinctness (Δ+) which
is a measure based on relatedness of species
(Clarke & Warwick 1998). To test whether a
set of species occurring at a sampled site has
the same taxonomic distinctness structure as a
so-called “master” list (i.e. an inventory of all
species in a given biogeographical region) from
which it was drawn, the Taxonomic Distinct-
ness Test (TAXDTEST) was performed (with
1000 random simulations) and the results were
presented as a funnel plot (for details see Clarke
& Warwick 2001 and Clarke & Gorley 2006).
The checklist of Silfverberg (1999) as updated
by Iglikowska and Namiotko (2010) and supple-
mented by the records from the Fauna Europaea
database (Horne 2004) was adopted as the inven-
tory of non-marine ostracod species for Fennos-

 Iglikowska & Namiotko   
candia, whereas for Poland, the updated checklist
of non-marine ostracods by Namiotko (2008)
served as the master faunal list. The higher classi-
cation of the ostracods followed Meisch (2000).
All statistical procedures were run in the
PRIMER ver. 6.1.10. programme (Clarke &
Gorley 2006), except CCA which was performed
using CANOCO ver. 4.56. (ter Braak & Šmilauer
1997–2009) software.
Results
A total of 40 300 ostracods were collected from
all study sites (11 157 from Lapland and 29 143
from Poland). At six sites (L5, L10, L23 in Lap-
land and P1, P18, P21 in Poland), no ostracods
were found. The main reasons for the absence
was probably either poor environmental condi-
tions: low pH (L10 = 4.3, P1 = 4.2), low calcium
content (L5 and L23 = 10 mg dm3), and low min-
eralization (conductivity L5 = 60.8, L10 = 56.3,
L23 = 57.5, P1 = 44.9, P21 = 64.3 µS cm), or too
short time for colonization of a new reservoir,
when a temporary pond re-lls after drought
(P18 and P21).
The average abundance of ostracods in the
remaining samples was 3061 ± 5450 ind. m–2
(mean ± SD). A total of 41 ostracod species were
identied (Appendices 3 and 4) — 15 in Lapland
and 35 in Poland. The average number of species
per site (species richness) was 4.3 ± 1.4 in Lap-
land and 6.3 ± 3.0 in Poland, and this difference
was signicant (Mann-Whitney test: U = 114.4,
p < 0.05).
Signicant differences in the average spe-
cies richness per sampling site within the habitat
types, were found only in Poland: on average
10.1 ± 0.7 species per site in PSL (the riparian
shallow lake waters), 4.1 ± 2.5 in PTW (the
temporary waters), and 2.6 ± 3.1 in PP (the peat-
bogs) (Kruskal-Wallis test: H = 15.2, p < 0.001).
In Lapland, the species richness was similar at
sites representing all three habitat types: 4.2 ±
1.5 in LSL, 4.4 ± 0.7 in LTW, and 3.7 ± 2.1 in LP
(Kruskal-Wallis test: H = 3.0, p = 0.224).
Also differences between average values of
the Shannon-Wiener diversity index for assem-
blages representing the three habitat types were
statistically signicant only in Poland (Kruskal-
Wallis test: H = 10.7, p < 0.01; H´ = 1.902 for
PSL, H´ = 1.245 for PTW and H´ = 0.755 for
PP).
In this study, 56% of the identied spe-
cies are considered to reproduce sexually, 29%
are characterized by the sporadic appearance of
males, and 15% are exclusively parthenogenetic.
In Lapland, the most widespread and abun-
dant species were Candona candida and Cyclo-
cypris ovum, each dominating at nine sites (38%
of the Lapland sites: Appendices 3 and 4) with
an average relative abundance of 37% and 39%,
respectively. A third most numerous species in
Lapland was Pseudocandona rostrata with an
average proportion of 10%. Rare species at the
Lapland sites included the crenophilic species
Cryptocandona reducta, C. vavrai, and Eucypris
pigra as well as Pseudocandona albicans. Only
one boreal/arctic species — Fabaeformiscan-
dona lapponica — was recorded in this area.
In Poland, the dominance structure of the
ostracod site assemblages was determined by
habitat type. In shallow lakes (PSL), no distinct
and common dominant species were found, but
those which were the most abundant (average
proportion > 5% in PSL) comprise species of the
genus Pseudocandona (both from the compressa
and rostrata groups, in total ca. 36%) as well
as Cyclocypris laevis (25%), Metacypris cor-
data (12%), Candona weltneri (7%), and Can-
donopsis kingsleii (6%) (Appendices 3 and 4). In
temporary waters (PTW), the dominant species
included Bradleystrandesia reticulata and Cypris
pubera (both with the average proportion of
ca. 30% in PTW), while Eucypris virens (13%)
and Pseudocandona pratensis (8%) contributed
smaller proportions. In the majority of the peat-
bogs in Poland (PP), either no ostracods or only
a few individuals were found (Appendices 3 and
4). At the few peat-bog sites at which ostracods
occurred, one species was always highly domi-
nant, either Cyclocypris globosa, Cypria ophtal-
mica or Pseudocandona stagnalis.
In the UPGMA cluster analysis (Fig. 2), four
types of ostracod assemblages were identied
and subsequently validated by the SIMPROF
signicance test (π = 3.95–4.50, p = 0.01). The
characteristic species (indicated by the SIMPER
analysis) of the rst assemblage type including
all site assemblages from the shallow riparian

   Ostracods ecology of subarctic and temperate Europe 
water of lakes in Poland (PSL) were: Pseudo-
candona spp. (usually represented by juveniles
not determined to species level), Candonopsis
kingsleii, Cypridopsis vidua, and Cypria ophtal-
mica as well as Cyclocypris laevis and Meta-
cypris cordata (Table 2), although the latter two
occurred at less than 3/4 of sites. Darwinula ste-
vensoni was not abundant but a relatively regular
inhabitant of the shallow lakes in Poland. The
average mutual Bray-Curtis similarity between
the site assemblages representing this assem-
blage type was 36.8%.
The second slightly less coherent (average
faunal similarity between site assemblages of
27.0%) assemblage type, which included all the
ostracod site assemblages from temporary waters
in Poland (PTW) (Fig. 2) was characterised by
four species already mentioned above: Cypris
pubera, Bradleystrandesia reticulata, Eucypris
virens and Pseudocandona pratensis (Table 2).
The third assemblage type linked only two
peat-bog sites in Poland (P6 and P23) and one
peat-bog site in Lapland (L18) (Fig. 2), and
displayed an average faunal similarity of only
19.6%. The main feature of these sites was
the 100% frequency of occurrence of Pseu-
docandona stagnalis, as well as a simultane-
ous presence of Cyclocypris globosa and Brad-
leystrandesia reticulata (Table 2 and Appendices
3 and 4).
P23
L18
P6
P14
P25
P22
P8
P20
P7
P15
P17
P16
P19
P11
P12
P2
P9
P13
P10
P24
L14
L24
P5
L3
L19
L1
L17
L20
L6
L11
L9
L16
L22
L7
L12
L15
L21
L2
L8
L13
Sites
100
80
60
40
20
0
Similarity
reg/hab LTW LP LSL PSL PTW PP
Fig. 2.

                
     
    



 Iglikowska & Namiotko   
Table 2.    


     

      
Darwinula stevensoni      
Candona candida      
Candona weltneri      
Candonopsis kingsleii      
Fabaeformiscandona fabaeformis     
Fabaeformiscandona hyalina      
Fabaeformiscandona lapponica     
Pseudocandona hartwigi      
Pseudocandona marchica       
Pseudocandona rostrata     
Pseudocandona stagnalis     
Pseudocandona albicans     
Pseudocandona compressa      
Pseudocandona insculpta      
Pseudocandona pratensis     
Pseudocandona sucki     
Cryptocandona reducta     
Cryptocandona vavrai     
Paracandona euplectella     
Cyclocypris globosa     
Cyclocypris laevis      
Cyclocypris ovum      
Cyclocypris serena     
Cypria exsculpta      
Cypria ophtalmica      
Ilyocypris decipiens      
Ilyocypris gibba      
Notodromas monacha      
Cyprois marginata     
Cypris pubera     
Cypridopsis vidua      
Bradleystrandesiafuscata     
Bradleystrandesia reticulata     
Eucypris crassa     
Eucypris pigra     
Eucypris virens     
Tonnacypris lutaria     
Heterocypris incongruens     
Dolerocypris fasciata      
Limnocythere inopinata      
Metacypris cordata      
The last assemblage type was dened by a
major cluster and consisted of all but one (see
above) site assemblages from Lapland and two
assemblages from peat-bog sites in Poland (P5
and P24; Fig. 2). The main species indicated
by the SIMPER analysis as principally respon-
sible for the separation of this set of samples
included Candona candida (occurring at 95% of
the sites within this assemblage type) as well as
Cyclocypris ovum and Pseudocandona rostrata
(each found at 71% sites) (Table 2). The average
similarity between all pairs of site assemblages
in this cluster was 31.8%.
According to the ANOSIM test carried out
using the faunal data, there were statistically sig-
nicant differences in the site assemblage struc-

   Ostracods ecology of subarctic and temperate Europe 
ture between Poland and Lapland (r = 0.363,
p < 0.001). However, when the analysis was
conducted assuming a grouping by habitat type
within the region (six sets of site assemblages),
the differences between the habitat types were
signicant only in Poland (r ≥ 0.599, p ≤ 0.002).
All the site assemblages in Lapland had a homo-
geneous species composition regardless of habi-
tat (r < 0.063, p > 0.189; Table 3).
The PCA ordination of the sampled sites
showed that the rst three axes explained 59.2%
of the total variation (Fig. 3). The factors which
determined most of the variance in all sampled
sites were conductivity and calcium ion content,
as well as organic matter and the water content of
the bottom sediments. Four abiotic factors were
responsible for separation of the peat-bogs from
Poland (PP): (1) high content of organic matter
in sediment, (2) high content of dissolved iron
in the water, (3) low concentration of dissolved
oxygen, and (4) low pH. The temporary waters
in Poland (PTW) and the shallow riparian waters
of lakes in Poland (PSL) were both dened by:
(1) conductivity, (2) pH, (3) dissolved oxygen
content, and (4) dissolved phosphate and nitrate
content. Moderate values of these factors were
typical fo the PSL sites, whereas high (and very
high) values typied the PTW sites. The sites in
Table 3. r 
a priori 

      

     
   0.926 0.825 0.504
   0.948 0.842 0.566
   0.618 0.671 0.214
    0.874 0.599
     0.714
–4 –2 0 4
PC1
–4
–2
0
2
4
PC2
reg/hab
LTW
LP
LSL
PSL
PTW
PP
L1
L2
L3
L4
L6
L7
L8
L9
L22
L12
L11
L13
L14
L15
L16
L18 L17
L19
L20
L21
L24
P19
P20
P14
P15
P8
P7
P13
P10
P9
P25
P22
P17
P16
P23
P24
P4
P5
P6
P11
P12
P3
P2
lat
long
alt
temp
OmgpH
cond
trans
Fe
Ca
PO
org
hydr
2 6
Fig. 3. 
    

   
     
  
   
  
   
   
   
   

  
    
    
   

   

    
 
   
    
   
    


 Iglikowska & Namiotko   
Lapland, regardless of habitat, formed a single
cluster distinguished by: (1) high transparency
of the water, (2) high organic matter content and
water content of the bottom sediment (for values
of environmental variables measured at particu-
lar sites see Appendices 1 and 2).
The ANOSIM analysis carried out on the
matrix of environmental factors conrmed the
division of sites into two regional groups (r =
0.379, p < 0.001). When grouping the sites by
habitat type within the region, however, the only
statistically signicant differences were found in
Poland between sites representing three different
habitats (r ≥ 0.252, p ≤ 0.015; Table 3), reect-
ing the results obtained from the faunal data (see
above and Table 4).
After the estimation of the gradient length
by Detrended Correspondence Analysis (5.802),
the CCA ordination was performed to explore
the relationships between independent (environ-
mental) and dependent (species abundance) vari-
ables. The rst two axes accounted for 60.6%
of the total variance of the species–environ-
ment relation, and the species–environment cor-
relations were 0.938 for the rst axis and 0.791
for the second axis (Table 5). In the analysis,
latitude was taken as a covariable and longitude
was excluded as a result of forward selection.
Five variables appeared signicant and most
important in explaining the observed ostracod
distribution (Fig. 4): Ca (F = 5.71, p = 0.002,
λA = 0.65), pH (F = 3.27, p = 0.002, λA = 0.35),
water conductivity (F = 3.17, p = 0.002, λA =
0.32), organic matter content of the sediment
(F = 2.09, p = 0.004, λA = 0.20) as well as dis-
solved oxygen content (F = 2.04, p = 0.002, λA
= 0.20). Conductivity and Ca content had the
strongest correlations with the rst canonical
axis, whereas pH and organic matter content of
bottom sediment correlated with the second axis.
As can be seen in the CCA plot (Fig. 4) there
is an interdependence between high values of
dissolved oxygen, conductivity and calcium con-
tent, and abundances of Bradleystrandesia fus-
cata, Cypris pubera, Cyprois marginata, Eucyp-
ris crassa, E. virens, Heterocypris incongruens,
Pseudocandona albicans, P. pratensis, P. sucki
and Tonnacypris lutaria. These species, which
are plotted on the right side in Fig. 4, are char-
acteristic of temporary waters. In the bottom-left
sector of the plot there are a number of species
(Candona weltneri, Candonopsis kingsleii, Cyp-
ridopsis vidua, Darwinula stevensoni, Fabaefor-
miscandona hyalina, Limnocythere inopinata,
Table 4. r
 a priori  

     
   0.681 0.657 0.894
   0.534 0.600 0.700
   0.567 0.713 0.623
    0.252 0.710
     0.751
Table 5. 
     
    
    
     
    
     
     
     
     

   Ostracods ecology of subarctic and temperate Europe 
Metacypris cordata, Pseudocandona compressa,
P. insculpta, Pseudocandona sp. and rostrata
group) the abundances of which are correlated
with high oxygen content values and high pH.
Furthermore, the abundances of the aforemen-
tioned species revealed negative correlation with
iron content (e.g. C. kingsleii Spearman’s cor-
relation: r = –0.42, p < 0.01 and D. stevensoni
r = –0.44, p < 0.01). In the upper-left sector of
the plot, there are species that are characteristic
of Polish peat-bogs, namely Cyclocypris glo-
bosa, Cypria ophtalmica, Fabaeformiscandona
fabaeformis, Paracandona euplectella and Pseu-
docandona stagnalis, and their occurrences and
abundances proved to be associated with low
pH, high organic matter content in the bottom
sediment, low values of dissolved oxygen and
low calcium content. Finally, it is worth noticing
that species characteristic for Lapland are absent
from the plot (only the 26 best tted species
were taken into consideration) as a consequence
of a lack of any strong relationships between
ostracod abundances and environmental factors
in Lapland.
The BEST analysis selected six signicant
and most important environmental factors and
geographical variables determining the grouping
of the ostracod site assemblages into four main
Omg Ca
cond
pH
org
Axis 1 (13.4%)
Axis 2 (6.8%)
Fig. 4.
Bradleystrandesia fuscataCan-
dona weltneri Candonopsis kingsleii Cyclocypris globosa, Cypria ophtalmica Cypridopsis
vidua Cypris puberaCyprois marginataDarwinula stevensoniEucypris crassaEucy-
pris virensFabaeformiscandona fabaeformisFabaeformiscandona hyalinaHeterocypris incongru-
ens Limnocythere inopinataMetacypris cordataParacandona euplectella Pseudocandona
albicans Pseudocandona compressaPseudocandona insculptaPseudocandona pratensis
Pseudocandona stagnalisPseudocandona suckiPseud Pseudocandona rostrata 
rostrataPseudocandonaTonnacypris lutaria


 Iglikowska & Namiotko   
clusters (Fig. 2), i.e. four assemblage types (r =
0.503, p = 0.01), these were: latitude, pH, con-
ductivity, dissolved iron content, phosphates and
organic content of the bottom sediment. Remark-
ably four of these (latitude, pH, conductivity and
organic matter content) also appeared as signi-
cant in the CCA ordination. Latitude naturally
separates all ostracod assemblages found in
Poland (< 54°27´N) from those found in Lapland
(> 66°28´N). Low pH segregates assemblages
of acidic sites (pH < 5.3 in peat-bogs in Poland)
from all the other assemblages at sites which are
characterized by more alkaline conditions with
moderate to high pH values. Conductivity subdi-
vides the ostracod assemblages into three groups:
(1) assemblages of low conductivity sites (< 180
µS cm–1) in Lapland and the peat-bogs in Poland,
(2) assemblages of moderate conductivity sites
of shallow lakes in Poland, and (3) assemblages
of the highly mineralised (> 800 µS cm–1) tem-
porary waters in Poland. Dissolved iron con-
tent is a factor that typies assemblages of the
shallow lakes in Poland where values are close
to zero (< 0.05 mg dm–3). Low phosphate con-
tent (< 0.25 mg dm–3) characterizes assemblages
occurring in Lapland, moderate PO4
–3 values
characterize assemblages of Polish shallow lakes
and peat-bogs, whereas very high PO4
–3 values
(> 1.00 mg dm–3) are typical from assemblages
from temporary waters. Finally, organic matter
content in the sediment typies the assemblages
found in Polish peat-bogs.
Funnel plots (Fig. 5) were generated using
TAXDTEST to compare the taxonomic diver-
sity (expressed as Δ+) of the ostracod assem-
blages found in Poland and in Lapland relative
to the known non-marine ostracod diversity of
the corresponding region. They show that in both
regions the ostracod assemblages are representa-
tive of the known regional taxonomic diver-
sity. It is noteworthy that in Poland there were
statistically signicant differences in the aver-
age taxonomic distinctness (Δ+) between the
habitat types (Kruskal-Wallis test: H = 10.08, p
= 0.007), the highest Δ+ values were typical for
the assemblages from shallow lakes (PSL), while
moderate values were found for those from tem-
porary waters (PTW) and peat-bogs (PP) (mean
Δ+ value ± SD for PSL = 75.76 ± 7.13 versus
that for PTW = 66.71 ± 4.35 and that for PP =
53.25 ± 11.99). However, the power of the per-
formed test was low because most of the assem-
blages from the peat-bogs (four of seven) had
to be excluded from the analysis due to the low
abundances (less than 30 ind. m2) and species
richness (less than two species) of the samples.
Discussion
In this study of three types of freshwater habitats
(temporary waters, shallow riparian water of lakes
and peat-bogs) in Poland, a total of 35 ostracod
species was identied, which constitutes 25% of
the total number of modern fresh- and brackish-
water ostracod species reported from Poland (140,
see Namiotko 2008). In the Lapland sites repre-
senting the same three habitat types, 15 species
were found representing 42% of the total number
of freshwater ostracod species recorded in this
region, i.e. 36 species reported the overall from
the Norwegian, Swedish, Finnish and Russian
parts of the Fennoscandia north of the Arctic
Circle (according to Sars 1890, Ekman 1908,
1914, Alm 1914a, 1914b, 1915, Sars 1925, Aka-
tova & Järvekülg 1965, Vekhov 2001, Iglikowska
& Namiotko 2004, 2010). No species new to
Norway, Finland or Poland were collected.
In Poland, there were statistically signicant
differences in average species richness (number
of species) of ostracod site assemblages occur-
ring in the three different habitat types. The high-
est number of species was collected from lake
sites and the lowest from peat-bogs. Thus shallow
riparian lake habitats seem to provide more suit-
able and more stable environmental conditions
for ostracods as compared with temporary astatic
waters and peat-bogs. An important factor result-
ing in high ostracod species richness in lakes is
the presence of emergent vegetation in the ripar-
ian zone, which creates a broad range of ecologi-
cal niches (Cooke et al. 2001, Søndegaard et al.
2005). In peat-bogs and temporary pools we stud-
ied, emergent vegetation was either non-existent
or sparse, so the ostracod fauna was relatively
poor in species. Habitats provided by temporary
waters are highly specic, inhabiting organisms
have relatively short life cycles, an ability to
survive desiccation, and tolerate high and uc-
tuating concentrations of dissolved organic and

   Ostracods ecology of subarctic and temperate Europe 
inorganic matter (e.g. Williams 2006). Ostracods
inhabiting temporary pools are adapted to survive
in such variable environments, they have desic-
cation-resistant stages (resting eggs or juvenile
and adult torpidity), short life cycles, photope-
riod-dependent egg hatching, parthenogenetic or
mixed (where both sexual and asexual lineages
occur) reproductive modes or can exhibit a bet-
hedging strategy (e.g. Horne 1993, Otero et al.
1998, Mezquita et al. 2005, Martins et al. 2008).
The extremely low diversity and abundance
of ostracods observed in peat-bogs was most
probably linked to low pH and resulting low
availability of dissolved calcium and other ions.
Freshwater ostracods have relatively large car-
apaces, mainly composed of calcium carbon-
ate, therefore it is commonly believed that they
require quite high levels of available calcium
in the environment to construct their carapace
valves. However, we need to know more about
complexities of the valve calcication in ostra-
cods (Mezquita et al. 1999a, Holmes & Chivas
2002).
The distinction between the three habitat
types in Poland was also revealed by the Shan-
non-Wiener diversity index. There were signi-
2 3 8 10 11
Number of species
20
30
40
50
60
70
80
90
100
reg/hab
PSL
PP
PTW
2 3 6
20
30
40
50
60
70
80
90
100
Δ
+
Δ
+
reg/hab
LP
LSL
LTW
4 5 7 8
4 5 6 7 9
Fig. 5.   
 
 Δ  
  
    
   

   
   Δ 


 Δ   
  

 
  
   
   
 Δ   
   
   
    


 Iglikowska & Namiotko   
cant differences in the species diversity between
assemblages from the three habitat types
(Kruskal-Wallis test: H = 10.74, p < 0.01). The
highest values of the Shannon-Wiener diversity
index were found in the assemblages from shal-
low lakes in Poland, and probably reected the
relative permanence and low variability of these
lacustrine environments, relative to temporary
waters and peat-bogs. Heino (2000) reported
that species diversity increases with the size of
a lake, larger water bodies contain more habitats
and consequently more potential niches (Søn-
degaard et al. 2005). In this study, the lakes had
the highest surface areas and hence the higher
values of the Shannon-Wiener diversity index.
Heino (2000) reported other factors inuenc-
ing diversity in lakes such as heterogeneity of
water habitat, provenance of bottom sediment
(autochthonous remains of Sphagnum mosses
and humic materials versus allochthonous
fallen leaves of deciduous trees and shrubs),
and amount of riparian vegetation. The results
reported herein add pH to Heino’s (2000) list of
factors inuencing diversity. Our results show
a statistically signicant correlation between
pH and observed values of the diversity index
(Spearman’s correlation: r = 0.46, p < 0.01).
Those sites typied by low environmental het-
erogeneity, with autochthonous bottom sediment
and lacking macrophytes were poorest in species
richness, conditions that are characteristic of
peat-bogs in Poland, where the lowest values of
the diversity index were found. In Lapland, the
average values of the Shannon-Wiener diversity
index were similar in the three types of habitat,
and generally lower than in Poland (average H´
= 1.074 and 1.377 in Lapland and in Poland,
respectively). This is in accord with the gener-
alization that species diversity decreases towards
the north (Heino 2002, Willig et al. 2003). There
were signicant differences in species diversity
between Poland and Lapland, but such a gradi-
ent was not observed within the studied regions.
The inuence of latitude on the species diversity
in the north may be the result of longer persist-
ence of the last glaciation at higher latitudes,
so that species had less time to colonize these
areas. History, however, does not seem to be the
only major determinant of species richness in the
northern areas (Heino 2002).
As regards the reproductive mode, 23 of the
41 species identied in the study are consid-
ered to reproduce sexually (Meisch 2000). The
remaining 18 species probably reproduce par-
thenogenetically at the sampling sites, although
for 11 of these, rare males or sexual populations
are reported in the literature (Meisch 2000).
In Lapland, nine out of 15 recorded species
(60%) are known to be fully parthenogenetic
(consisting of female-only populations or with
sporadic occurrence of rare males). On the other
hand in Poland, 60% of all the the recorded
species reproduce sexually. The sex ratio in all
studied species was heavily biased in favour of
females, with one exception — Candona welt-
neri at P9. In that case, sampling probably took
place during the season when males dominated
the adult population, since in this species mature
males and females are known to appear at dif-
ferent times (Hiller 1972). In Poland, there was
a signicant relationship between the ratio of
parthenogenetic to sexual species and habitat
type (Kruskal-Wallis test: H = 14.08, p < 0.001).
The largest proportion of species with asex-
ual reproduction was sampled from temporary
waters (mean ± SD = 81.2% ± 29.2%), while
signicantly lower proportions were observed
in peat-bogs (mean ± SD = 6.8% ± 13.4%) and
shallow lakes (mean ± SD = 4.5% ± 2.5%).
Parthenogenesis enables a population to grow
rapidly, so that it can quickly exploit any new
reservoir (e.g. when a temporary pond re-lls
after drought), thus asexual or mixed reproduc-
tive strategies can be an advantageous adapta-
tion in unpredictable habitats (Horne & Martens
1999, Mezquita et al. 2005, Martins et al. 2008).
In lakes and peat-bogs, the environmental condi-
tions are generally more stable, and sexual repro-
duction appears to be a more favourable mode.
Analysis of the assemblages in Lapland showed
no statistically signicant difference in the ratio
of parthenogenetic species between habitat type
(Kruskal-Wallis test: H = 0.105, p = 0.949).
Four types of ostracod assemblages were
distinguished using the UPGMA cluster analysis
(Fig. 2). The assemblage from temporary waters
in Poland was distinguished by four species:
Cypris pubera, Eucypris virens, Bradleystran-
desia reticulata and Pseudocandona pratensis,
which are characteristic of temporary pools

   Ostracods ecology of subarctic and temperate Europe 
(Sywula 1974, Meisch 2000, Gifre et al. 2002).
Similarly, few species found in the assemblage
from Polish peat-bogs (mainly Cyclocypris glo-
bosa and Pseudocandona stagnalis) are typical
inhabitants of this habitat (Sywula 1965, 1974,
Fryer 1993, Meisch 2000). The assemblage type
in shallow riparian water of lakes in Poland,
consisted of two sets of species: (1) a group of
moderately dominant eurybiontic species (Cyp-
ridopsis vidua, Darwinula stevensoni, Cypria
ophtalmica, Cyclocypris laevis, Candonopsis
kingsleii and Candona candida), and (2) a group
of less abundant species typical of central Euro-
pean lakes (Candona weltneri, Pseudocandona
insculpta, P. marchica, P. hartwigi, Metacypris
cordata and Limnocythere inopinata) (Sywula
1974, Meisch 2000).
In Lapland, we did not nd a strong relation-
ships between abundances of the ostracod spe-
cies and the observed environmental parameters,
with one exception. The abundance of Candona
candida was negatively correlated with organic
matter content in bottom sediments (r = –0.06,
p < 0.01). In contrast, abundance of this species
correlated positively with latitude (r = 0.59, p
< 0.001), which implies that it prefers cooler
waters of northern Europe. Kiss (2007) found
that this species’ abundance correlated nega-
tively with water temperature, and Külköylüoğlu
et al. (2007) reported a negative correlation with
air temperature (r = –0.508, p < 0.05). Based on
our results and previous papers, C. candida is
conrmed as an oligothermophilic species, pre-
ferring oligotrophic conditions.
Signicantly stronger species–environment
relationships were found in Poland. The group of
species consisting of Bradleystrandesia fuscata,
Cypris pubera, Eucypris crassa, E. virens, Pseu-
docandona albicans, P. pratensis and P. sucki,
which were placed on the right side of the CCA
plot (Fig. 4), appeared to be associated with rela-
tively high values of conductivity, oxygen con-
tent and calcium content. High values of envi-
ronmental factors are characteristic of temporary
pools, and E. virens almost exclusively inhabits
astatic water bodies (Sywula 1974, Mezquita
et al. 1999b, Meisch 2000, Gifre et al. 2002,
Külköylüoğlu et al. 2007). This species tolerates
not only high concentrations of dissolved sub-
stances, but also signicant uctuations of salin-
ity, temperature, oxygen and nutrient content
(Gifre et al. 2002). Külköylüoğlu et al. (2007)
also reported a positive correlation between E.
virens abundance and conductivity but a nega-
tive one with pH.
The lacustrine species were grouped in the
bottom-left sector of the CCA ordination plot
(Fig. 4). These species correlate with environ-
mental factors such as high pH, and high content
of dissolved oxygen. Phytophilic Cypridopsis
vidua was recorded in a range of habitats, but
it is most often found in lakes (Sywula 1974,
Meisch 2000). This species is reported to require
high oxygen concentrations (≥ 5 mg dm–3) (Kiss
2007), and its oxyphilic nature was conrmed in
the present study. The species was recorded at
sites with an average O2 concentration of 6.2 mg
dm–3. Cypridopsis vidua tolerates well a broad
range environmental factors, even relatively high
concentrations of pesticides (Külköylüoğlu et al.
2007). However, it is doubtful whether C. vidua
should be considered a polythermophilic species
(Meisch 2000), since it is widespread and abun-
dant in Lapland. An organism with high oxygen
requirement is often well adapted to low water
temperatures (Mikulski 1982).
The BEST analysis distinguished ve envi-
ronmental factors and one geographical variable
which had signicant impact on the grouping of
the ostracod assemblages: pH, conductivity, Fe
and phosphate contents, organic matter content
in sediment, as well as latitude. The inuence of
geographical position is most likely linked to cli-
matic effects. Mezquita et al. (2005) and Poquet
and Mesquita-Joanes (2011) showed latitude as
one of the most important factors determin-
ing the distribution of freshwater Ostracoda in
Europe. Species living in the north have to toler-
ate not only low temperatures, but often also low
concentrations of dissolved ions and nutrients.
In Lapland, waterbodies are frozen for more
than half a year, therefore, the species living
there must be able to survive such conditions
at least during one stage of their life cycle. The
Lapland sites were situated either on the western
slopes (sites L1–L7) or on the eastern slopes
(sites L8–L24) of the Scandinavian Mountains.
Although east and west sites experienced signi-
cantly different climatic regimes, there were no
differences either in their environmental charac-

 Iglikowska & Namiotko   
teristics or in the abundances and species com-
position of the ostracod assemblages between
the two sides of the Mountains.
Many authors have reported that pH sig-
nicantly affects freshwater invertebrates (e.g.
Wickins 1984, Lampert & Sommer 1997, Ros-
setti et al. 2004, Martins et al. 2009, Martins et
al. 2010). Each aquatic organism has its own pH
optimum and tolerance range, but if pH exceeds
this range, species cannot survive because the
regulation of pH within the organism is energeti-
cally too costly (Lampert & Sommer 1997).
Ionic content of the medium can have a
strong inuence on the diversity of freshwa-
ter ostracods (e.g. Mezquita et al. 2005, Pieri
et al. 2007, 2009). The in situ ionic equilib-
rium of water can have an effect on both the
osmoregulation and the physiological control of
an organism’s internal ionic balance. In fresh-
waters, calcium is often the critically limiting
ion, and crustaceans such as ostracods require
calcium for their carapaces (Lampert & Sommer
1997). Calcium is effective in buffering pH, so
in Ca-depleted environments organisms are far
more susceptible to extremes of pH (Wickins
1984). The importance of calcium availability
in controlling and limiting the post-embryonic
development of ostracod individuals, as well
as occurrence and diversity of ostracod species
and assemblages has been demonstrated in sev-
eral works (e.g. Mezquita et al. 1999a, Holmes
& Chivas 2002, Viehberg 2006), although the
intensity of the effects depends largely on spe-
cies.
The analysis of the relationships between the
species composition and dominance in the ostra-
cod assemblages indicated that in Lapland, the
species diversity was lower than that in temper-
ate Poland and that most of the species recorded
in the north appeared to be eurybiontic. No
distinct differences in the structure of the ostra-
cod assemblages among the three types of fresh-
water habitats studied in this subarctic region
were found. Freshwater biodiversity in northern
Europe is low probably as a result of the short
growing season of the aquatic plants, the lack
of adequate nutrients and hence the low primary
production. Species with long life cycles cannot
successfully colonize these habitats, because the
season is too short for them to complete their
ontogeny (not every species can survive being
frozen as mature or juvenile). Development can
take much longer in Lapland because of lower
water temperatures. Finally, the geological char-
acter of the rocks may be important: in Lapland,
rocks are mostly acidic which results in natural
waters having low pH and being low in cal-
cium (Stebel et al. 2007). Both factors limit the
diversity of the ostracod populations and in Lap-
land none of the observed ostracod species have
strongly calcied carapaces.
In northern Fennoscandia, numerous ponds
and small lakes are a feature of the landscape,
in some parts of the region there are 1500
waterbodies per 10 km2 (Raatikainen & Kuu-
sisto 1990, Rautio et al. 2011). We infer that
the majority of these waterbodies in Lapland
become temporarily connected during spring-
time, when snowmelt water raises water levels,
and hence facilitates the dispersion of aquatic
organisms such as ostracods among all water
bodies and the colonization of new ones. Con-
sequently, not only do the environmental param-
eters become uniform throughout but also the
ostracod site assemblages are homogenized. This
inference is one of several possible hypotheses
that may explain our results: it however deserves
further, more comprehensive investigation.
In Poland, the temporary pools and the peat-
bogs are inhabited almost exclusively by sets
of ostracod species that are specic to these
habitats. These species can be used as indicator
species for each of these habitats.
Temporary waters studied in Poland were
located in cultivated elds, in the vicinity of
villages and towns, or in roadside ditches. The
inow into these temporary water bodies is by
rainwater running off elds or roads, potentially
enriched with fertilizers, pesticides, manure and
pollutants such as oil residues. Therefore, it is
not surprising that these temporary waterbod-
ies were found to contain high concentrations
of nitrogen, phosphate and mineral compounds.
During warm and dry summer, the water gradu-
ally dries up, and concentrations of dissolved
inorganic and organic substances become pro-
gressively higher. The species that inhabit these
waterbodies must have the ability to tolerate
high nutrients concentration, wide temperature
ranges, and hypoxic conditions. Before these

   Ostracods ecology of subarctic and temperate Europe 
waterbodies nally dry up, specialist species lay
desiccation-resistant eggs and enter diapause.
For many species, the optimal reproductive
strategy in temporary waters is parthenogenesis,
because even a single egg can be sufcient to
ensure recolonisation of a waterbody when it re-
lls (Mezquita et al. 2005).
The main interrelated problems facing
aquatic organisms inhabiting peat-bogs are low
pH and lack of calcium ions (or the difculty in
their uptake). Ubiquitous bog-mosses (Sphag-
num spp.) not only acidify the water, but also
decomposition of a dense mass of decaying moss
utilizes much of the dissolved oxygen in the
water and all of it in the underlying peat. Only
some specially adapted species can tolerate these
extreme conditions.
In the lakes in Poland, typical diurnal oscilla-
tions in O2 and CO2 concentrations and pH shift
the balance between photosynthesis (increas-
ing oxygen levels, reducing CO2 and increasing
the alkalinity) and respiration (reducing oxygen
levels, increasing carbon dioxide concentrations
and hence reducing pH). When pH and oxygen
concentrations increase, ionic iron changes
from soluble ferrous ions to insoluble ferric ions
which tend to precipitate in the form of ferric
hydroxide. As a result, iron was not detectable in
the water column of the Polish lakes. The littoral
zone of a lake supports a high species diversity
and while there are specialized lake species, the
lakes are also inhabited by eurybiontic species.
Acknowledgements
This work was supported by funds from the University of
Gdańsk (project no. BW-1411-5-0337-6) and by EU Marie
Curie Research and Training Network (contract no. MRTN-
CT 2004-512492). Special thanks go to Geoff Boxshall and
Martin Angel for their valuable comments on the manuscript.
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 Iglikowska & Namiotko   
Appendix 1. 
          
 
  
             
            
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             

   Ostracods ecology of subarctic and temperate Europe 
Appendix 2. 
          
 
  
             
            
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             
             

 Iglikowska & Namiotko   
Appendix 3. ND
 

                       
                 
                       
 
                       
  
                       
                       
                       
 
                       
  
                       
                       
 
                       
 
                       
                 
                       
 
                       
                 
                       
 
                       
                 
                       
      
                       
 
                       
                 
                       
                 
                       
           
                       
                     

Bradleystrandesia
reticulata
Candona candida
C. candida

Cryptocandona
reducta
Cryptocandona
vavrai
Cyclocypris
globosa
Cyclocypris ovum
C. ovum 
C. vidua 
Cyclocypris
serena
Cypria ophtalmica
Cypridopsis vidua
Dolerocypris
fasciata
Eucypris pigra
Eucypris 
Fabaeformiscandona
lapponica
Pseudocandona
albicans
Pseudocandona
rostrata
Pseudocandona
stagnalis
Pseudocandona 



   Ostracods ecology of subarctic and temperate Europe 
Appendix 3. ND
 

                       
                 
                       
 
                       
  
                       
                       
                       
 
                       
  
                       
                       
 
                       
 
                       
                 
                       
 
                       
                 
                       
 
                       
                 
                       
      
                       
 
                       
                 
                       
                 
                       
           
                       
                     

 Iglikowska & Namiotko   
Appendix 4.  N D
   

            
       
            
        
             
             
            
            
            
            
            
              
             
        
            
             
             
           
             
              
Appendix 4. 
            
              
    
      
             
            
           
            
    
    
    
    
            
     
        


    
              

Bradleystrandesia
fuscata
B. reticulata
Candona candida
C. weltneri
Candona 
Candonopsis kingsleii
Cyclocypris globosa
C. laevis
C. ovum
Cypria exsculpta
C. ophtalmica
Cypridopsis vidua
Cypris pubera
Cyprois marginata

   Ostracods ecology of subarctic and temperate Europe 
Appendix 4.  N D
   

            
       
            
        
             
             
            
            
            
            
            
              
             
        
            
             
             
           
             
              
Appendix 4. 
            
              
    
      
             
            
           
            
    
    
    
    
            
     
        


    
              

Darwinula stevensoni
Dolerocypris fasciata
Eucypris crassa
E. virens
Fabaeformiscandona
fabaeformis
F. hyalina
Fabaeformiscandona 
Heterocypris incongruens
Ilyocypris decipiens
I. gibba
Limnocythere inopinata
Metacypris cordata
Notodromas monacha
Paracandona euplectella

 Iglikowska & Namiotko   
Appendix 4. 
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
             

Pseudocandona albicans
P. compressa
P. compressa
P. hartwigi
P. insculpta
P. marchica
P. pratensis
P. rostrata
P. stagnalis
P. sucki
Pseudocandona 
Tonnacypris lutaria

