Plant Syst Evol (2008) 276:73–87
DOI 10.1007/s00606-008-0084-1
ORIGINAL ARTICLE
Genetic differentiation and postglacial migration
of the Dactylorhiza majalis ssp. traunsteineri/lapponica
complex into Fennoscandia
Sofie Nordström Æ Mikael Hedrén
Received: 20 March 2008 / Accepted: 21 July 2008 / Published online: 20 September 2008
Ó Springer-Verlag 2008
Abstract Eight variable regions (microsatellites, insertion/deletion and duplication regions) from the plastid
DNA genome were analyzed for 91 populations belonging
to Dactylorhiza majalis ssp. traunsteineri and closely
related taxa. A total of 36 composite plastid haplotypes
were found. The two dominating haplotypes had a clear
geographic distribution suggesting at least two separate
immigration routes into Scandinavia after the last glaciation: one southwestern route and one or two southeastern
routes. D. majalis ssp. traunsteineri could not be clearly
separated from any of the other taxa included in the study
except for D. majalis ssp. sphagnicola. The morphologically similar taxa D. majalis ssp. traunsteineri, D. majalis
ssp. lapponica and D. majalis ssp. russowii showed no
genetic differentiation, and therefore we suggest an amalgamation of the three taxa into one broadly circumscribed
subspecies; D. majalis ssp. lapponica. The plastid data also
revealed incidents of hybridization and possible introgression between D. majalis ssp. lapponica and other members
of the genus, e.g., D. incarnata.
Keywords Phylogeography Plastid DNA
Hybridization Narrow-leaved marsh-orchid
Lapland marsh-orchid Dactylorhiza traunsteineri
Dactylorhiza russowii Dactylorhiza lapponica
S. Nordström (&) M. Hedrén
Department of Ecology, Plant Ecology and Systematics,
University of Lund, Sölvegatan 37, 223 62 Lund, Sweden
e-mail: sofie.nordstrom@ekol.lu.se
Introduction
Fennoscandia was covered with ice during the last glaciation (c. 22,000 to 17,000 cal yrs BP) and was not
completely ice-free until approximately 8,000 years ago.
Gradually, plants hibernating in refugial areas outside the
ice sheet recolonized the open habitats left by the ice.
Immigration routes and histories of Fennoscandian populations have been described for various species (e.g.,
Picea abies in Lagercrantz and Ryman 1990; Picea abies
in Kullman 1996; Silene dioica in Malm and Prentice
2002; Calluna vulgaris in Rendell and Ennos 2002; Carex
digitata and Melica nutans in Tyler et al. 2002; Betula
pendula in Palmé et al. 2003; Dactylorhiza maculata s.l.
in Ståhlberg 2007). Populations in previously glaciated
areas may be genetically depleted as a consequence of
repeated bottlenecks during stepwise migration, a pattern
that has been described for several species of deciduous
forest trees (e.g., Ferris et al. 1998; King and Ferris
1998). Such species seem to have been located in distant
southern refugia during the last ice age. Plants with a
more temperate distribution have, however, been shown
to be equally genetically variable in Fennoscandia as
populations of the same taxon in other parts of Europe
(Tyler et al. 2002; Borgen and Hultgård 2003; Palmé
et al. 2003; Skrede et al. 2006; Ståhlberg 2007). These
temperate species may have had refugia close to the ice
sheet (Stewart and Lister 2001) and seem to have kept
most of their genetic variation during the migration process. Additionally, many plant species have colonized
Fennoscandia through more than one immigration route
(Hultén 1950; King and Ferris 1998; Nordal and Jonsell
1998; Malm and Prentice 2005; Ståhlberg 2007), which
may have further contributed to comparatively high levels
of genetic diversity.
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74
Another factor affecting the genetic diversity of immigrated temperate species is the occurrence of polyploidy.
Polyploid plant species are thought to increase in number
with latitude in the Northern Hemisphere (Löve and Löve
1974; Grant 1981; Otto and Whitton 2000; Brochmann
et al. 2004) and, for example, 44% of the plant taxa in
boreal areas of the Arctic are polyploids compared to 82%
in the polar desert further north (Brochmann et al. 2004).
Several studies have shown that polyploids have higher
levels of genetic diversity than their related diploids (e.g.,
Soltis and Rieseberg 1986; Lumaret and Barrientos 1990;
Luttikhuizen et al. 2007) and due to their multiple chromosome complements they might have a higher potential
for storing their genetic diversity during repeated bottleneck episodes associated with recolonization of previously
glaciated areas.
Dactylorhiza Necker ex Nevski (Orchidaceae) is an
example of a temperate plant genus with members of different ploidy levels. It is dominated by a polyploid
complex consisting of diploid and tetraploid taxa. The
complex must have originated well before the Weichselian
glaciation (Hedrén et al. 2007) and is now found in large
parts of Europe and Asia Minor (Pridgeon et al. 2001;
Delforge 1995). During the ice ages, the Balkans (Hedrén
et al. 2007), central Europe, and parts of central Russia
(Ståhlberg 2007) acted as the most important refugia for
the complex. Subsequent migration to formerly glaciated
areas probably happened rapidly due to efficient seed dispersal by small seeds (Dressler 1993) and availability of
suitable habitats (Adams 1997; Adams and Faure 1997).
D. maculata (L.) Soó s.l. and D. incarnata (L.) Soó s.l.
are the present-day representatives of the parental lineages
that built up the polyploid complex of Dactylorhiza in
Europe (Hedrén 1996). Repeated hybridizations between
the parental lineages have given rise to several allotetraploid derivatives (Hedrén 2003). This reticulate evolution
has yielded a large amount of morphological variation in
the complex which makes species delimitation difficult.
Hybridization between present day representatives of the
complex has often been considered as an additional factor
contributing to further taxonomic confusion (Mossberg and
Nilsson 1987; Baumann and Künkele 1988; Delforge
2001). Moreover, it could be discussed whether morphologically distinct populations represent independent
evolutionary lineages arising from separate polyploidization events, or they have differentiated from widespread
taxa as a consequence of genetic drift or selection. In the
former case it may be motivated to recognize deviating
forms as species, whereas in the latter case they may
merely be seen as slightly deviant local forms without
taxonomic value. Depending on underlying principles of
species delimitation, different authors have recognized
between one (Pedersen et al. 2003) and 23 (Delforge 1995)
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S. Nordström, M. Hedrén
tetraploid species. Here we mainly follow the taxonomic
delimitation of taxa as in Delforge (2001) but treat all
allotetraploid taxa as subspecies of D. majalis (Rchb.) P. F.
Hunt & Summerh. as suggested by Pedersen et al. (2003).
One of the most common and variable allotetraploid is D.
majalis (Rchb.) P. F. Hunt & Summerh. ssp. traunsteineri
(Saut.) H. Sund., which was originally described on basis
of material collected at Schwarzsee, Kitzbühel, Austria.
Populations referable to this taxon have subsequently been
reported from a wide area of northern Europe, including
the Fennoscandian-Baltic region and the British Isles,
although the taxonomic status of material from these latter
regions has often been discussed and there is no consensus
among present authors. It is characterized by having bluishgreen leaves that are usually spotted on the upper surface,
acute leaf apex, and a few-flowered, lax inflorescence with
fairly large purple flowers provided with a prominent
median lip lobe (Delforge 2001; Mossberg and Stenberg
2003). The value of leaf spotting as key character has
however been questioned as it often varies within and
between populations (Hylander 1966). D. traunsteineri has
repeatedly been divided into subspecies and varieties
(Hylander 1966; de Soó 1980) and morphologically distinct
forms from certain areas have often been recognized
(Hylander 1966; Hansson 1994; Andersson 1995). In the
Fennoscandian-Baltic area two further taxa have been
recognized that are clearly linked to D. majalis ssp.
traunsteineri; D. majalis (Rchb.) P. F. Hunt & Summerh.
ssp. lapponica (Laest.) H. Sundermann (Hylander 1966;
Senghas 1968; de Soó 1980; Andersson 1996) and D.
majalis (Rchb.) P. F. Hunt & Summerh. ssp. russowii
(Klinge) H. Sund. (Senghas 1968; Mossberg and Nilsson
1987; Andersson 1994). D. majalis ssp. lapponica has a
northern and alpine distribution whereas D. majalis ssp.
russowii can be found in the Baltic countries and in Russia.
The three taxa are not only morphologically similar but
also grow in similar habitats. For instance, both D. majalis
ssp. traunsteineri from southern Sweden and ssp. russowii
from the East of the Baltic sea are found in calcareous fens
growing in association with, e.g., Carex lepidocarpa
Tausch ssp. lepidocarpa, Schoenus ferrugineus L., Primula
farinosa L. and Epipactis palustris Crantz. The abovementioned members of Dactylorhiza are the central focus
for this study and subsequently denoted ‘‘the core complex’’. The core complex may sometimes be hard to delimit
from other allotetraploid taxa in the Fennoscandian-Baltic
area. For example, D. majalis (Rchb.) P. F. Hunt & Summerh. ssp. sphagnicola (Höppner) H. A. Pedersen &
Hedrén (Hylander 1966; Ekman 1985; Bjurulf 2005) has
some flower characters in common with ssp. traunsteineri
but is normally found in poor fens and is not associated
with indicator species of calcareous fens (Mossberg and
Nilsson 1987; Baumann et al. 2006).
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
As mentioned above several morphological studies have
been made to clarify the relationships between the different
taxa in the core complex but no fine scale genetic analyses
have been performed up to now. To be able to elucidate
variation patterns and taxonomic limits within this group of
closely related taxa we used fast-evolving plastid markers
of microsatellite type for this study. The plastid genome is
uniparentally inherited (presumably maternally in orchids,
Corriveau and Coleman 1988; Cafasso et al. 2005) and
markers thereof are commonly used in phylogeographic
and phylogenetic studies (summarized in Lowe et al.
2004). Another important aspect of plastid markers, especially when studying allopolyploids, are the infrequence of
recombination (Wolfe and Randle 2004), a problem associated with data sets from the nuclear genome.
The specific aims of this study were (1) to describe the
genetic differentiation within the core complex in Fennoscandia and the Baltic area, (2) to describe limits between
the core complex and other allotetraploid members of
Dactylorhiza occurring in the area, and (3) to describe
geographic variation patterns and relate these patterns to
potential recolonization routes into Scandinavia after the
last ice age.
Materials and methods
Plant material
Six hundred and fifty individuals from 91 populations were
included in this study (Appendix). Two or more floral buds
or apparently un-pollinated flowers with bracts were collected from each specimen and immediately dried in silica
gel (Chase and Hills 1991). A majority of the populations
(79) belonged to the core complex (D. majalis ssp. traunsteineri, ssp. russowii and ssp. lapponica) and the sampling
covered most of its distribution in Fennoscandia (mainly
Sweden, Norway and Finland) and Estonia. Additionally,
five populations of D. majalis ssp. traunsteineri were
sampled in Russia, Lithuania and Austria. One of the
Austrian populations was from the type locality of ssp.
traunsteineri near Kitzbühel. We did not separate out the
subordinate taxon sometimes associated with D. majalis
ssp. traunsteineri, ssp. curvifolia, but plants in agreement
with this form were included from populations in both
Finland and Sweden.
Most of the material in the core complex was easy to
identify whereas some populations were more or less
intermediate between the three subspecies. Accordingly,
there are both typical D. majalis ssp. traunsteineri populations and ambiguous populations within the core complex
included in this study. Moreover, 11 populations from
Norway and middle Sweden were classified as D. majalis
75
ssp. traunsteineri in local floras or by field botanists, but
approached ssp. sphagnicola in our opinion. Morphologically, the two subspecies can be separated by differences in
the spur: ssp. sphagnicola is characterized by a narrow,
cylindrical and decumbent spur, whereas ssp. traunsteineri
is characterized by a slightly wider, conical and straight
spur (Delforge 2001; Bjurulf 2005; Baumann et al. 2006).
The ambiguity of the populations motivated the inclusion
of some populations of D. majalis ssp. sphagnicola as
reference material. As further reference material, populations of all the remaining allotetraploid species of
Fennoscandia were included: D. majalis (Rchb.) P. F. Hunt
& Summerh. sspp. majalis, praetermissa (Druce) D. M.
Moore & Soó, purpurella (T. Stephenson & T. A. Stephenson) D. M. Moore & Soó and baltica (Klinge) H.
Sund. Earlier studies (Devos et al. 2003; Hedrén 2003;
Shipunov et al. 2005; Pillon et al. 2007) of plastid DNA
variation in Dactylorhiza have shown that allotetraploid
Dactylorhiza have inherited their plastid genomes from
D. maculata s.l, which means that D. maculata s.l and not
D. incarnata s.l. is the seed parent of the allotetraploids. If
more recent hybridization between an allotetraploid and
D. incarnata has occurred, and D. incarnata has served as
the seed parent, the D. incarnata plastid haplotype can be
seen in the allotetraploid, but probably only in a fraction of
plants within populations. In order to discover such
secondary hybridization we also included one population
of D. incarnata as a reference. The taxonomic classifications of the plant material in this study were based on
scientific floras (Hylander 1966; de Soó 1980), field floras
(Krok and Almquist 1994; Mossberg and Stenberg 2003)
and local expertise. Voucher material of all populations
(dried flowers) has been deposited at the Lund botanical
museum (LD).
Molecular methods
Total DNA was extracted by the CTAB (cetyltrimethyl
ammonium bromide) method (Doyle and Doyle 1990).
Eight polymorphic plastid loci were analyzed for each
sample. Five of the loci were mononucleotide repeats, two
were duplicated regions and one was an insertion/deletion
region. All loci were selected because of their high polymorphism for the genus, (previously tested by Hedrén et al.
unpublished). All the alleles were defined according to size
and combined into haplotypes. Detailed information of the
loci and primers is given by Table 1. PCR conditions for
all fragments were as follows: 5.6 ng DNA was amplified
using 0.26 lM Cy5 labeled primer, 0.26 lM unlabeled
primer, 1.6 mM MgCl2, 210 lM dNTP’s, 19 PCR buffer
(Applied Biosystems) and 0.12 U Amplitaq Gold polymerase (Applied Biosystems), in a total volume of 5 lL.
The PCR profile was: 94°C 1 min, Ta (Table 1) 1 min,
123
76
S. Nordström, M. Hedrén
Table 1 Detailed information on the loci and primers used in this study. Ta = annealing temperature
Locus Type
Approximate Location
fragment size
Primers
Primer sequence (50 -30 )
Ta (°C)
Cy5trnL5e
CGAAATCGGTAGACGCTACGC
57
trnLR5
CGTTAGAACAGCTTCCATTG
1
polyAa
183–186
trnT–trnL intergenic spacer
6
dupl regionb
177–367
psbC–trnS pseudospacer
6B
dupl regionb
460–610
psbC–trnS pseudospacer
8
polyTc
73–76
rps19–psbA intergenic spacer
9
indel regionc
171–202
rps19–psbA intergenic spacer
Cy5trnS2
AGAGTTTCAGGTCCTACCTA
psbC2
GTGTTCCTAACTGCCCACTT
Cy5trnS1f
GGTTCGAATCCCTCTCTCTC
trnS2f
TAGGTAGGACCTGAAACTCT
Cy5HK7F
HK8R
CACCTAGACACTTATCATTC
CCGATTTCTCCAAATTTTCG
54
Cy5HK9R
CTAGCTTCTGTGGAAGTTCC
54
HK8F
CGAAAATTTGGAGAAATCGG
10B
polyA-AT-Tc 138–163
psbA–trnK exon 1 intergenic spacer Cy5trnK1Ag CCGACTAGTTCCGGGTTCGA
11B
polyAc
82–87
rpl16 intron
19
polyTd
137–149
trnS–trnG intergenic spacer
a
54
56
HK10F
GAAAGGCTTGTTATTTCACAG
Cy5F71h
GCTATGCTTAGTGTGTGACTCGTTG 53
F71R2
AGTTTATAGTGGGGTCAGCC
Cy5trnSGf3
GAGTAATAGTGTTCTAATAAGAG
trnSGr3
CAGACGCAGTCAAGATAGCA
58
Soliva and Widmer (1999)
b
Hedrén (2003)
c
Hedrén et al. (unpublished)
Pillon et al. (2007)
d
54
e
Hedrén et al. (unpublished); Taberlet et al. (1991)
f
trnS, Demesure et al. (1995)
g
trnK, Demesure et al. (1995)
h
F71, Jordan et al. (1996)
72°C 1 min 30 s for 40 cycles. PCR fragments were
labeled and separated on an ALF Express II automated
sequencer (Amersham Biosciences). Size determination
was performed using ALFwin Fragment Analyser 1.03.01
software.
Data analysis
Population differentiation patterns were summarized in two
multidimensional scaling diagrams (MDS; Kruskal 1964a,
b) using the computer program NT-SYSpc 2.2 (Rohlf
2005). In both calculations Nei’s average number of differences between populations (Nei and Li 1979) were
calculated between all pairs of populations in the computer
program Arlequin 3.01 (Excoffier et al. 2005) and used as
input matrix for the multidimensional scaling analysis.
Relationships between all haplotypes were illustrated in
a Median-joining network assisted by the program NETWORK 4.5 (Bandelt et al. 1999) with all options set to
default.
To test whether genetic distances were correlated to
geographic distances between populations a Mantel test
(Mantel 1967) was performed using NT-SYSpc 2.2 (Rohlf
123
2005). A geographic distance matrix based on Euclidian
distances was compared with a genetic distance matrix
based on Nei’s average number of differences between
populations (Nei and Li 1979). The geographically distant
Russian and Austrian populations were excluded from the
test, as we were primarily interested in the correlation
between genetic and geographic distances in the Scandinavian/Baltic area.
Results
Characterization of haplotypes
Using eight variable loci, 36 haplotypes were found among
the 650 analyzed individuals (annotated H1–H36; Table 2).
Two of the haplotypes (H1 and H4) counted for more than
60% of the individuals and 13 of the haplotypes (H1, H2,
H4–H8, H10–H12, H17, H18, and H21) counted for more
than 91% of the individuals. The relationships between
haplotypes and their relative frequencies can be seen in the
haplotype network (Fig. 1). Three distinct haplotype
groups appeared in the network. The first group, denoted
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
77
Table 2 Combined haplotypes detected in the present study by means of markers described in Table 1. N is numbers of individuals found with a
particular haplotype
No.
Locus (bp)
N
1
6
6B
8
9
10B
11B
19
1
185
222
470
75
196
145
84
149
246
2
185
222
470
75
196
146
84
149
10
3
4
185
185
367
222
610
470
73
76
171
189
138
148
86
84
137
148
1
150
5
185
222
470
75
196
143
84
149
17
6
185
281
560
73
177
146
85
149
13
7
186
281
560
73
177
146
85
149
6
8
185
281
560
73
177
147
85
149
31
9
185
281
560
73
177
148
85
149
5
10
185
222
470
73
177
150
85
149
23
11
184
367
610
73
171
138
85
137
21
12
184
367
610
73
171
138
86
137
13
13
185
191
560
76
189
140
84
149
5
14
184
367
610
73
171
138
84
137
1
15
186
222
470
75
196
145
84
149
1
16
185
222
470
73
196
138
84
137
1
17
185
222
470
75
196
145
84
148
32
18
19
185
185
222
222
470
470
75
75
196
196
146
148
84
84
148
149
11
1
20
185
222
470
76
196
148
84
148
1
21
185
222
470
76
202
140
84
149
25
22
185
367
610
75
196
145
84
149
4
23
185
222
470
75
185
145
84
149
3
24
183
367
610
73
171
143
86
137
2
25
185
222
470
75
189
143
85
148
7
26
185
281
560
75
177
148
85
149
1
27
185
222
610
73
171
138
86
137
1
28
185
281
560
74
177
147
85
149
4
29
184
367
610
73
171
141
86
137
2
30
184
367
610
73
171
140
85
137
1
31
185
222
470
76
189
148
84
149
3
32
184
367
610
73
171
142
86
137
2
33
186
222
470
76
189
148
84
148
1
34
35
184
185
367
222
610
470
73
74
171
196
140
146
86
84
137
149
2
1
36
185
281
560
74
177
148
85
149
2
group I, included most of the haplotypes and was divided
into two subgroups, dominated by haplotypes 1 and 4,
respectively. The second group, to the left in Fig. 1, consisted mainly of haplotype 6 to haplotype 10 and was
denoted group II. In the right end of the network several
rare haplotypes, e.g., H11 and H12, clustered into the third
group, denoted incarnata group. Haplotype 1 was the most
common haplotype and a lot of rare haplotypes were
connected to it, e.g., H15, H22 and H23. In contrast, haplotype 4, which was the second most common haplotype,
only connected to a few rare haplotypes, e.g., H20. Haplotype 21 had a somewhat distant position in relation to the
other haplotypes of the second group with only haplotype
13 connected to it.
Population differentiation
The MDS diagram based on average pairwise differences
between haplotypes and including all populations is given
as Fig. 2. Three main clusters appeared in the MDS. The
123
78
S. Nordström, M. Hedrén
Fig. 1 Median-joining
network of all haplotypes
included in this study. Distances
correspond approximately to the
number of changes between
haplotypes. All the haplotypes
are numbered and the three
haplotype groups are indicated
Fig. 2 Multidimensional scaling analysis of all populations included
in this study. The three clusters mentioned in the text are indicated.
Stress = 0.17
cluster to the upper left included the reference population
of D. incarnata and five allotetraploid populations fixed for
incarnata haplotypes (H11 and H12). Less than four
samples were examined from any of these allotetraploid
populations. The cluster to the lower left contained the
three reference populations of D. majalis ssp. sphagnicola
and eight other allotetraploid populations dominated by
group II haplotypes. The larger cluster to the lower right
contained more than 60% of the examined populations.
Populations observed in between the three main clusters
were either constituted by two or more different haplotypes
from the three clusters or carried some of the odd haplotypes described below. Two dense subclusters that
appeared in the large cluster to the lower right were
included in a separate MDS given as Fig. 3. Haplotype 1
was prevalent in the populations in the left half of the
diagram in Fig. 3, whereas haplotype 4 dominated to the
right.
Taxonomic differentiation in haplotypes
The MDS diagram of all populations (Fig. 2) revealed no
separation of populations labeled as D. majalis ssp.
traunsteineri from other allotetraploid populations. The
123
D. majalis ssp. traunsteineri populations were evenly distributed along the axes and were interspersed by other taxa.
Other members of the core complex were also not distinct.
The populations of D. majalis ssp. lapponica did not form a
separate group in any of the MDS ordinations (Figs. 2, 3),
although all populations were included in the right cluster
of Fig. 2. The same result appeared for the ssp. russowii
populations (Figs. 2, 3). Similarly, the three D. majalis ssp.
majalis populations as well as the two populations of ssp.
purpurella were located among ssp. traunsteineri populations (Figs. 2). However, the reference population of D.
majalis ssp. praetermissa was located below the right
cluster and the populations of ssp. baltica were placed
within the upper left cluster or half-way between this
cluster and the right cluster (Fig. 2). All the populations of
D. majalis ssp. sphagnicola were situated in the lower left
cluster in Fig. 2. This cluster also contained the 11
ambiguous populations with uncertain affinity to D. majalis
ssp. traunsteineri from Norway and middle Sweden (populations 24, 26, 28, 29–32, 42, 49–51), which all carried
some of the typical ssp. sphagnicola haplotypes from
haplotype group II. The three populations of D. majalis ssp.
majalis had different haplotypes including H4, H21 and
H25. Haplotype 21 was also present in four populations of
D. majalis ssp. traunsteineri and two of ssp. lapponica, all
from the mixed region in Northern Lapland. Haplotype 25
is a rare haplotype unique to one of the D. majalis ssp.
majalis populations and has not been found elsewhere. The
single population of D. majalis ssp. praetermissa from
Denmark contained the unique haplotype H13.
Geographic variation within the core complex
The MDS ordination given as Fig. 3 was based on 52
populations of the core complex. (All the populations in
the two groups of the lower right cluster in Fig. 2 plus the
21 adjacent populations, populations of D. majalis ssp.
praetermissa and ssp. majalis were excluded). Groups
separated along the horizontal axis had different geographic origins. Notably, the left side contained all
populations from the southern Swedish mainland whereas
all populations from Gotland but one were located on the
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
Fig. 3 Multidimensional
scaling analysis of populations
of the right cluster of Fig. 2.
Only populations of the core
complex are included.
Stress = 0.10
79
1.1
R
A
F
A
F
F
F
II -0.1
F
F
A
R
-1.2
-1.4
0.3
ssp. traunsteineri
ssp. lapponica
ssp. russowi
several taxa
Northern Lapland
Rest of Mainland
Gotland
Finland
Austrian Alps
Russia
2.0
I
right side. The right group was more geographically
widespread than the left and contained populations from
Russia, Austrian Alps and all but one of the Finnish
populations.
Some populations were located between the main clusters, including populations from Finland, Sweden and
Estonia. The Swedish populations were all from north of
the southern border of Lapland (64°150 N) and the Finnish
populations were north of the Gulf of Bothnia.
The geographic pattern seen in Fig. 3 was also evident
in Fig. 4a, where core complex populations containing
haplotypes 1 and 4 were marked:
Haplotype 1 was totally dominating on the Swedish
mainland apart from northern Scandinavia. It was not
found in central Finland and only rarely encountered in
Norway. On Gotland we only found two individuals containing haplotype 1 in one single population (out of seven
populations examined). This haplotype was also present in
Estonia and Lithuania. Haplotype 4 had a more eastern
distribution and was most common in Finland and on
Gotland. Additionally, it was found in Estonia and Austria.
There were also populations from northern Sweden and
northern Norway containing haplotype 4 and the haplotype
could be found as far south as southern Lapland. This
distribution of haplotypes created a mixed zone in northern
Fennoscandia where both haplotypes 1 and 4 were present
and sometimes observed in the same populations. There
were other meeting zones of the two haplotypes in Estonia
(Hiiumaa and Saaremaa) and on Gotland (Sweden). Only
one population (D. majalis ssp. traunsteineri) fixed for
haplotype 1 was found on Gotland while two such populations were encountered in Estonia (ssp. russowii).
Moreover, there was a population of D. majalis ssp. russowii on Saaremaa carrying this haplotype together with
haplotype 4.
The map given as Fig. 4b shows the distribution of a
less common haplotype, H10, which was found in D.
majalis ssp. traunsteineri populations on Gotland and in
ssp. russowii populations on Saaremaa and Hiiumaa.
Haplotype 10 was strongly divergent from the other haplotypes encountered in the core complex and most closely
related to the D. majalis ssp. sphagnicola haplotypes
(Fig. 1). Except for Gotland and Estonia it was also found
in Austria.
Almost all populations initially labeled as D. majalis
ssp. traunsteineri from Norway and four populations from
central Sweden were fixed for typical D. majalis ssp.
sphagnicola haplotypes (Fig. 4c).
A weak but highly significant positive correlation,
0.18975, was observed between geographic and genetic
distances among populations from the Fennoscandic-Baltic
area (Mantel test; p \ 0.001).
Discussion
Haplotype evaluation
Plastid markers are commonly used in phylogeographic
studies due to their relatively slow mutation rate and
123
80
S. Nordström, M. Hedrén
A
B
63
62
15 18 17
34 27
63
62
80
73
87
57
19
86
73
67
14
67
14
16
41
40
40
56
88 38
54
25
37
37
35
55
58
39
56
88 38
54
53
55
58
59
48
59
13
48
36
52
52
Karelia
24
23
Karelia
49
42
76
74 78
77
75
84 83
31
32 26
28
84 83
29
79
72
7
60 61
75
30
10
5
72
4
70
71
89
47
8 7
60 61
68 69
45
74 78
77
79
82
81
6
44
43
46
69
36
50 51
76
23
82
19
86
16
41
53
85 20
80
87
57
35
15 18 17
33
33
43
46
90
44
6
10
5
12 91
11
9
45
89
47
66 64
3
22
65
22 21
Austria
1 2
Austria
1 2
C
34 27
63
62
15 18 17
33
87
85 20
80
73
57
19
86
67
14
16
41
40
39
56
88 38
54
25
37
35
53
55
58
59
13
48
52
36
50 51
24
23
Karelia
49
42
76
31
32 26
28
84 83
29
75
30
74 78
77
79
82
81
72
68 69
4
8 7
60 61
44
43
46
45
70 90
89
71
47
6
10
5
12 91
11
9
66 64
3
65
22 21
Austria
1 2
Fig. 4 Geographic distribution of haplotypes. a Core complex
populations containing haplotype 1 and/or 4. Black symbols populations containing haplotype 4. White symbols populations containing
haplotype 1. Grey symbols populations with individuals carrying
haplotype 1 as well as individuals carrying haplotype 4. b Populations
containing haplotype 10. Black symbols populations carrying haplotype 10. c Populations containing group II haplotypes. Black symbols
populations totally dominated by individuals with group II haplotypes
123
(100% carry the haplotypes). Grey symbols populations with a lesser
content of individuals carrying group II haplotypes (less than 50%
carry the haplotypes). White symbols populations with no individuals
of group II haplotypes. Populations 68, 70 and 71 are allopatric D.
majalis ssp. sphagnicola populations, whereas the other populations
with black symbols are identified as D. majalis ssp. traunsteineri
populations
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
uniparental origin. However, for the same reasons, plastid
markers may not be suitable for distinguishing between
closely related taxa. Introgression of plastid DNA as a
result of interspecific hybridization may further complicate
phylogeographic studies based on plastid data. However,
the mutation rate may differ substantially between plastid
microsatellite loci and when combining several loci with
different mutation rates into combined haplotypes a more
structured pattern may appear. Furthermore, the fact that
orchids have very small seeds and thus have the capacity
to spread over long distances suggests that the gene
flow by seeds may be more important than pollen flow
(discussed in Cozzolino et al. 2003). In this study, the
eight chloroplast markers proved to be very informative
when answering our questions on both taxonomy and
phylogeography.
Thirty-six haplotypes were found in the distribution area
out of which two (H1 and H4) were present in more than
60% of the samples. Despite the high frequencies of these
two haplotypes, we found variation within populations and
often variation within a small defined area.
Gene flow by hybridization
Most allotetraploid populations in this study had plastid
haplotypes previously characterized as typical D. maculata s.l. haplotypes. This finding confirms the common
notion that D. maculata s.l. has acted as donor of the
plastid genome at the polyploidization event (Devos et al.
2003; Hedrén 2003; Shipunov et al. 2005; Pillon et al.
2007). Further, the finding that two clearly defined and
large subgroups of haplotypes dominate in the core
complex (characterized by H1 and H4, respectively)
supports earlier results suggesting multiple origins of allotetraploids in Dactylorhiza (Hedrén 1996, 2003; Devos
et al. 2006). However, no present day representatives of
D. maculata s.l. carrying haplotype 4 have been found in
spite of a large sample surveyed from the major part of
the European distribution area (Ståhlberg 2007), and a D.
maculata s.l. ancestor carrying this haplotype should have
been found if it still existed. The high number of allotetraploid populations carrying haplotype 4 and the wide
distribution of this haplotype in the allotetraploids suggest
that haplotype 4 might be an old haplotype originating
well before the last glaciations and that different allotetraploid taxa carrying this haplotype share a common
history. The alternative explanation to the observed pattern is that haplotype 4 has differentiated from another
allotetraploid haplotype, for example haplotype 1 which is
also widespread in present day D. maculata s.l. However,
4 to 12 mutations at four loci out of eight studied is
required for that conversion and we consider this a less
likely scenario.
81
Some of the allotetraploid populations had haplotypes
typical of D. incarnata (Fig. 2). It is hypothetically possible that these populations have inherited the incarnata
plastids at some polyploidization events. However, since
the number of individuals carrying the incarnata haplotypes is low, only eight individuals in altogether five
populations, the presence of incarnata haplotypes rather
indicate backcrossing between the allotetraploids and D.
incarnata at a later stage. Introgression with D. maculata
s.l. may also take place, but is more difficult to detect since
the allotetraploids normally inherit the plastids from this
lineage. Nevertheless, the traunsteineri population 78 in
southern Sweden may show such a history. It contains two
haplotypes, the common traunsteineri haplotype 1 and one
individual with H7, a group II haplotype. In addition,
individuals of D. maculata s.str. that grow at the same
locality are dominated by haplotype 7 (Hedrén et al.
unpublished). It is however difficult to separate between
hybridization with D. maculata s.str. and hybridization
with D. majalis ssp. sphagnicola since they both carry
group II haplotypes. The same conclusions about introgression could be drawn for the two traunsteineri
populations 48 and 59 which carry a few individuals with
typical sphagnicola haplotypes. Previous studies on
Dactylorhiza have also reported introgression of allotetraploids by their parental lineages (Hedrén 2003; Aagaard
et al. 2005; Shipunov et al. 2005) as well as hybridization
between allotetraploids (Heslop-Harrison 1954; Hedrén
2003).
Taxonomy
We conclude that the pattern of plastid haplotype composition found in this study does not support the subdivision
of the core complex into three taxa. This conclusion is
strongly supported by previous (Andersson 1996) and
unpublished (Pedersen unpublished) findings on variation
in morphology of the core complex as well as earlier
genetic studies of the taxa using allozymes, AFLPs and
chloroplast data (Hedrén 1996; Hedrén et al. 2001; Hedrén
2003; Pillon et al. 2007). Therefore we suggest an amalgamation of the three taxa into one with the oldest name
applied: D. majalis ssp. lapponica.
Core complex individuals with the two most common
haplotypes (H1 and H4) sometimes grew at adjacent sites
or even in mixed populations. When examining such
populations in the field we found no obvious differences in
morphology between the two haplotypes. However, our
genetic data is in congruence with previous findings on
differentiation in morphology (Andersson 1994; Hansson
1994) and allozymes (Hedrén 1996) between populations
of D. majalis ssp. traunsteineri on Gotland and mainland
Sweden. Our results are also congruent with the finding
123
82
that D. majalis ssp. traunsteineri on Gotland and ssp.
russowii in Estonia are closely similar in morphology
(Andersson 1994). All individuals of the taxonomically
ambiguous populations (belonging to either D. majalis ssp.
traunsteineri or ssp. sphagnicola) from the area around
Oslo (Norway) and Gästrikland and Hälsingland (Sweden),
showed typical sphagnicola haplotypes. Therefore we
suggest that they should be treated as this taxon. In general,
all populations of D. majalis ssp. sphagnicola in this study
are well separated from the rest of the allotetraploids
(Fig. 2) which is in agreement with earlier studies (Hedrén
2003; Devos et al. 2006) and further strengthens the position of ssp. sphagnicola as a separate subspecies. In
contrast, our data indicates no clear differentiation between
D. majalis ssp. traunsteineri on the one hand and ssp.
majalis, ssp. purpurella or ssp. praetermissa on the other.
To confirm this finding additional analysis including more
material of all the different tetraploid taxa is needed.
As the interpretation of plastid markers could be hampered by chloroplast capture and that the results only show
genetic variation from one of the parents, nuclear markers
would better describe the reticulate evolution of polyploid
complexes. Consequently, newly developed nuclear
microsatellites (Nordström and Hedrén 2007) might be
useful for future studies of the problematic species delimitations in Dactylorhiza.
Geographic pattern
The distribution of the common haplotypes 1 and 4 in this
study shows a clear geographic pattern (Fig. 4a). The most
common haplotype (H1) is dominating the Swedish
mainland, particularly the southern parts, while haplotype 4
is prevalent in Finland, on Gotland (Sweden) and in
northern Scandinavia. The high frequencies of these two
haplotypes may be explained by rapid expansion after the
last glaciations of populations carrying these haplotypes
(cf. Hewitt 1996). On the basis of the present distribution
of the two haplotypes the immigration history for the
Scandinavian populations can be described. Two immigration routes are seen, carrying haplotype 1 and 4,
respectively: One southwestern route of haplotype 1 originating in continental Europe and entering the Swedish and
Norwegian mainland probably via Denmark, and one path
of haplotype 4 with a more eastern direction through Estonia and Finland to northern Sweden and Norway. This
immigration scenario is similar to results from earlier
studies of phylogeography in Scandinavia on both plants
(Nordal and Jonsell 1998; Berglund and Westerbergh 2001;
Malm and Prentice 2005) and animals (Jaarola and Tegelström 1995; Taberlet et al. 1995).
123
S. Nordström, M. Hedrén
Interestingly, the distribution of haplotype 4 also reveals
a connection between the Estonian islands Saaremaa and
Hiiumaa, and Gotland (Sweden) (Fig. 4a). The same connection is revealed by the distribution of the rare haplotype
10 (Fig. 4b). We interpret this pattern such that Gotland, as
well as Saaremaa and Hiiumaa are all colonized by the
same refugial population located somewhere to the southeast of the Baltic Sea. The dispersal to Gotland over the
Baltic Sea seems surprising since Gotland is located more
than 100 km from the eastern shore. However, the small
air-filled seeds of orchids may travel thousands of kilometers by wind (Jersáková and Malinová 2007) and
supposedly also by epizoochory. Haplotype 4 is also found
in D. majalis ssp. majalis from southernmost Sweden and it
may be hypothesized that the haplotype has spread to the
core complex on Gotland from these populations. However, the flowering times of D. majalis ssp. majalis and ssp.
traunsteineri are different and together with the fact that no
other population of ssp. traunsteineri on the Swedish
mainland carries the haplotype, such a spreading route does
not seem likely.
Recent studies on immigration history in Nordic plants
have revealed eastern refugia during the last glaciations
(e.g., Lagercrantz and Ryman 1990; Skrede et al. 2006;
Ståhlberg 2007). Haplotype 4 may have such an origin,
or alternatively it may have had refugia further south
since it is present in Austrian populations. Haplotype 1 is
ubiquitous in Europe including Russia (Ståhlberg 2007). A
study at a larger geographical scale may have the potential
to identify the refugial areas of the haplotypes found in this
study.
Haplotypes 1 and 4 meet in northern Fennoscandia.
Similar contact zones between colonizing genotypes are
seen for other species with southeastern and northwestern
immigration routes into Scandinavia (Berglund and Westerbergh 2001; van Rossum and Prentice 2004; Ståhlberg
2007) and could be explained by glacial history. The ice
cover in northern Scandinavia melted slowly and was
completely gone much later than in the adjacent areas
(Berglund 2004). This led to an accumulation of immigrating species on both sides of the ice sheet and as the last
remains of the ice melted populations of different origin
came into contact in approximately the same area. Another
meeting zone of haplotypes 1 and 4 is in Estonia, where
both haplotypes occur in close vicinity together with several others. Perhaps the genetic variation in Estonia could
be explained by its geographic location close to refugia.
To conclude, we did not find any support in plastid
haplotypes for separating D. majalis ssp. traunsteineri, ssp.
lapponica and ssp. russowii into three taxa. Considering
also the high degree of morphological similarity and results
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
from previous studies (Andersson 1994; Hedrén 1996;
Hedrén et al. 2001; Hedrén 2003; Pillon et al. 2007) we
suggest an amalgamation of the three taxa into D. majalis
ssp. lapponica. Furthermore, this broadly defined subspecies was not separated from other allotetraploids in the
study area why additional studies should be made on a
larger scale and with additional taxa. Newly developed
nuclear microsatellites (Nordström and Hedrén 2007) may
be used to bring clarity to the relationships of the genus.
The genetic variation in the core complex had a clear
geographic component and we have identified a minimum
of two immigration routes into Scandinavia after the last
glaciation.
83
Acknowledgments We would like to thank Sunniva Aagaard, Åse
Bøilestad Breivik, Stefan Ericsson, Sven Hansson, Ursula Malm,
Lennart Nordström, Tarmo Pikner, Mikko Piirainen, Mari Reitalu,
David Ståhlberg, Taavo Tuulik, Kai Vahtra and Finn Wischmann for
field assistance and/or collecting material. We also thank two anonymous reviewers for valuable comments. The study was supported by
grants from Lunds Botaniska Förening to SN and from the Crafoord
Foundation and the Swedish research council for environment, agricultural sciences and spatial planning, FORMAS (grant 2002-102) to
MH.
Appendix
Table 3
Table 3 Identification and geographic origin of populations of Dactylorhiza Neck. ex Nevski used in this study. Latitude and longitude
references are approximate
No.
Taxon
Country
Locality
Latitude
Longitude
Number of
individuals
1
D. majalis (Rchb.) P.F.Hunt &
Summerh. ssp. traunsteineri
(Saut.) H. Sund.
Austria
Tirol, Kitzbühel
47°27
12°23
10
2
D. majalis ssp. traunsteineri
Austria
Steiermark, Gusswerk
47°45
15°20
10
3
D. majalis ssp. purpurella (T. &
T.A. Stephenson) D.M. Moore
& Soó
Denmark
ØJy, Assens
55°16
09°54
6
4
D. majalis ssp. praetermissa
(Druce) D.M Moore & Soó
Denmark
VJy, Sjørups sø
56°52
09°24
8
5
D. majalis ssp. russowii (Klinge)
H. Sund.
Estonia
Hiiumaa, Järvamaa
58°48
22°50
2
6
D. majalis ssp. russowii
Estonia
Saaremaa, Kuusnömme
58°19
21°59
2
7
D. majalis ssp. russowii
Estonia
Saaremaa, Ninase
58°32
22°14
2
8
D. majalis ssp. baltica (Klinge)
H. Sund.
Estonia
Saaremaa, Vesiku
58°20
21°58
7
9
D. majalis ssp. baltica
Estonia
Saaremaa, Karala
58°16
21°55
3
10
D. majalis ssp. russowii
Estonia
Hiiumaa, Heistesoo
58°56
22°17
12
11
D. majalis ssp. russowii
Estonia
Saaremaa, Viidume
58°17
22°08
14
12
D. majalis ssp. russowii
Estonia
Jalase, Pedasmaa
58°28
22°07
1
13
D. incarnata (L.) Soó
Finland
Jyväskylä
62°14
25°44
12
14
D. majalis ssp. traunsteineri
Finland
Kn, Paltamo
64°19
28°03
10
15
D. majalis ssp. traunsteineri
Finland
KiL, Kaukonen
67°32
24°51
11
16
D. majalis ssp. traunsteineri
Finland
Kn, Korpijärvi
64°45
29°57
10
17
D. majalis ssp. traunsteineri
Finland
SoL, Moskuvaara
67°36
26°53
10
18
D. majalis ssp. traunsteineri
Finland
KiL, Mustavaara
67°37
25°23
10
19
D. majalis ssp. traunsteineri
Finland
OP, Haukipudas
65°13
25°25
5
20
21
D. majalis ssp. traunsteineri
D. majalis ssp. traunsteineri
Finland
Lithuania
PeP, Tervola
Kretinga, Kartena
66°05
55°55
25°02
21°28
11
1
22
D. majalis ssp. traunsteineri
Lithuania
Palanga, Nemirseta
55°53
21°04
1
23
D. majalis ssp. traunsteineri
Norway
Bu, Gjellebekk
59°49
10°18
10
24
D. majalis ssp. traunsteineri
Norway
Bu, Grimsrudsbrenna
59°43
10°06
2
25
D. majalis ssp. purpurella
Norway
MR, Giske, Molnes
62°34
6°05
5
26
D. majalis ssp. traunsteineri
Norway
Ak, Marimyr
59°46
10°51
2
27
D. majalis ssp. traunsteineri
Norway
No, Bodø
67°20
14°29
1
123
84
S. Nordström, M. Hedrén
Table 3 continued
No.
Taxon
Country
Locality
Latitude
Longitude
Number of
individuals
28
D. majalis ssp. traunsteineri
Norway
Te, Skien, Limitjern
59°16
09°30
6
29
D. majalis ssp. traunsteineri
Norway
Te, Siljan
59°18
09°49
6
30
D. majalis ssp. traunsteineri
Norway
Te, Skien
59°16
09°30
1
31
D. majalis ssp. traunsteineri
Norway
Vf, Djupedalsmyr
59°30
10°10
6
32
D. majalis ssp. traunsteineri
Norway
Vf, Holmestrand
59°30
10°10
1
33
D. majalis ssp. traunsteineri
Norway
No, Inndyr, Holtan
67°02
14°04
1
34
D. majalis ssp. traunsteineri
Norway
No, Inndyr, Øya
67°02
14°01
1
35
D. majalis ssp. lapponica (Laest.)
H. Sundermann
Norway
ST, Røros, Sølendet
62°34
11°23
3
36
D. majalis ssp. traunsteineri
Russia
Karelia, Petrozavodsk
61°47
33°48
9
37
D. majalis ssp. traunsteineri
Sweden
Ång, Edsele
63°16
16°36
14
10
38
D. majalis ssp. traunsteineri
Sweden
Ång, Överå
63°35
17°11
39
D. majalis ssp. traunsteineri
Sweden
Ång, Ramsele
63°31
16°25
2
40
D. majalis ssp. traunsteineri
Sweden
Ång, Svedbergsviken
63°37
15°58
10
41
D. majalis ssp. lapponica
Sweden
Jmt, Kalvberget
64°44
15°21
10
42
D. majalis ssp. traunsteineri
Sweden
Gstr, Axmarbruk
61°02
17°08
2
43
D. majalis ssp. traunsteineri
Sweden
Gtl, Agmyr
57°49
18°39
4
44
D. majalis ssp. traunsteineri
Sweden
Gtl, Harudden
57°55
18°42
15
45
D. majalis ssp. traunsteineri
Sweden
Gtl, Hoburgsmyr
57°49
18°50
4
46
D. majalis ssp. traunsteineri
Sweden
Gtl, Kauparve
57°49
18°53
14
47
48
D. majalis ssp. traunsteineri
D. majalis ssp. traunsteineri
Sweden
Sweden
Gtl, Lojsthajd
Hls, Los
57°20
61°37
18°19
14°54
15
13
49
D. majalis ssp. traunsteineri
Sweden
Hls, Marmaverken
61°16
16°52
2
50
D. majalis ssp. traunsteineri
Sweden
Hls, Nybo-stomyran
61°32
16°44
4
51
D. majalis ssp. traunsteineri
Sweden
Hls, Tröne, Berge
61°28
16°50
2
52
D. majalis ssp. lapponica
Sweden
Hrj, Hamra
62°34
12°15
6
53
D. majalis ssp. lapponica
Sweden
Hrj, Klinken
62°43
12°18
5
54
D. majalis ssp. traunsteineri
Sweden
Jmt, Handog
63°19
15°01
1
55
D. majalis ssp. lapponica
Sweden
Jmt, Skalberget
62°34
14°27
15
56
D. majalis ssp. lapponica
Sweden
Jmt, Vackermyran
63°28
15°20
10
57
D. majalis ssp. lapponica
Sweden
LyL, Blomstervallen
65°41
15°10
10
58
D. majalis ssp. traunsteineri
Sweden
Mpd, Granboda
62°34
15°42
7
59
D. majalis ssp. traunsteineri
Sweden
Mpd, Måckelmyran
62°15
17°27
18
60
D. majalis ssp. traunsteineri
Sweden
Ög, Hagebyhöga
58°27
14°56
9
61
D. majalis ssp. traunsteineri
Sweden
Ög, Kärna mosse
58°25
15°32
11
62
63
D. majalis ssp. traunsteineri
D. majalis ssp. lapponica
Sweden
Sweden
Nb, Jupukka
Nb, Suksijoki
67°17
67°20
23°14
23°13
9
4
64
D. majalis. ssp. majalis
Sweden
Sk, Eskeröd
55°46
14°07
11
65
D. majalis ssp. majalis
Sweden
Sk, Örup
55°30
13°55
10
66
D. majalis ssp. majalis
Sweden
Sk, Saxtorp
55°49
12°56
10
67
D. majalis ssp. traunsteineri
Sweden
Vb, Slätmyran
64°56
20°27
7
68
D. majalis ssp. sphagnicola
(Höppner) H. A. Pedersen &
Hedrén
Sweden
Sm, Dumme mosse
57°45
14°00
5
69
70
D. majalis ssp. traunsteineri
D. majalis ssp. sphagnicola
Sweden
Sweden
Sm, Eksjö
Sm, Jonsbo fly
57°38
57°03
14°46
15°50
11
2
71
D. majalis ssp. sphagnicola
Sweden
Sm, Sjömaden
56°53
15°52
3
72
D. majalis ssp. traunsteineri
Sweden
Srm, Sjösa
58°45
17°07
12
123
Genetic differentiation and postglacial migration of D. majalis ssp. traunsteineri/lapponica complex
85
Table 3 continued
No.
Taxon
Country
Locality
Latitude
Longitude
Number of
individuals
73
D. majalis ssp. lapponica
Sweden
LyL, N. Fjällnäs
65°45
15°30
10
74
D. majalis ssp. traunsteineri
Sweden
Upl, Bladåker
59°59
18°18
2
75
D. majalis ssp. traunsteineri
Sweden
Upl, Ed
60°17
18°19
2
76
D. majalis ssp. traunsteineri
Sweden
Upl, Gårdskär
60°37
17°37
7
77
D. majalis ssp. traunsteineri
Sweden
Upl, Gunnarsmaren
59°42
19°02
8
78
D. majalis ssp. traunsteineri
Sweden
Upl, Norrmarjum
59°53
18°40
9
79
D. majalis ssp. traunsteineri
Sweden
Upl, Rimbo
59°44
18°19
9
80
D. majalis ssp. lapponica
Sweden
LyL, Rödingsträsket
65°42
15°07
3
81
82
D. majalis ssp. traunsteineri
D. majalis ssp. traunsteineri
Sweden
Sweden
Vg, Jättened
Vg, Sjogerstad
58°19
58°19
14°41
13°46
17
3
83
D. majalis ssp. traunsteineri
Sweden
Vsm, Myggkärret
59°24
14°46
6
84
D. majalis ssp. traunsteineri
Sweden
Vsm, Röjängen
59°26
14°47
8
85
D. majalis ssp. lapponica
Sweden
Nb, Armasjärvi
66°19
23°30
10
86
D. majalis ssp. lapponica
Sweden
Vb, Bjurträsk
64°59
19°34
10
87
D. majalis ssp. lapponica
Sweden
LyL, Joeström
65°45
14°57
11
88
D. majalis ssp. traunsteineri
Sweden
Ång, Junsele
63°35
17°11
10
89
D. majalis ssp. traunsteineri
Sweden
Gtl, Kallgatburg
57°41
18°40
10
90
D. majalis ssp. traunsteineri
Sweden
Gtl, Klinte
57°35
18°21
10
91
D. majalis ssp. russowii
Estonia
Jalase, Parka
59°00
24°33
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