Allozyme Variation in Diploid, Polyploid and Mixed-Ploidy Populations of the Pilosella alpicola Group (Asteraceae): Relation to Morphology, Origin of Polyploids and Breeding System

The Pilosella alpicola group includes four species (P. alpicola s.str., P. ullepitschii, P. rhodopea and P. serbica) with allopatric distributions (Alps, Balkans, Carpathians) and contrasting cytotype patterns (diploid, diploid-polyploid and polyploid species). Whereas diploid taxa (P. ullepitschii and P. serbica) reproduce sexually, the mode of reproduction of polyploid cytotypes reflects their origin: autopolyploids of P. rhodopea reproduce sexually, while allopolyploid cytotypes of P. alpicola s.str. apomictically. We used allozymes to elucidate overall genetic variation within the group and to test their utility for taxon discrimination, assessment of polyploid origin and possible correlations with breeding systems. Variation of five allozyme systems encoded by eight polymorphic loci and 29 alleles was studied in 20 populations and 298 plants representing all taxa. Allozymes were proved to be only of limited usefulness for the taxonomic classification within the P. alpicola group. The Western Carpathian populations of P. ullepitschii formed the only genetically well-differentiated group. The same allele suite shared by all cytotypes of P. rhodopea and presence of both balanced and unbalanced heterozygotes in tetraploids was consistent with autopolyploid origins of polyploids and provided further evidence for a primary contact zone. An isolated relic population of P. rhodopea from the Southern Carpathians exhibited lowered values of genetic diversity when compared to the core area. Pronounced fixed heterozygosity was found in P. alpicola s.str., supporting its allopolyploid origin. In accordance with assumptions, genotypic variability was significantly higher in sexually reproducing diploid and diploid-polyploid taxa than in apomictic P. alpicola s.str.     

<Emphasis Type="Italic">Lecanora flavoleprosa</Emphasis> (Lecanoraceae,lichenized Ascomycota) found in the Carpathians

The recently described, terricolous and corticolous, sorediate lichen Lecanora flavoleprosa (belonging to the L. symmicta group) is for the first time recorded from the Carpathians. So far, this rare European species has only been reported from a few localities in the Austrian and Swiss Alps, and Fennoscandia (Norway and Sweden). In this paper several records from the Polish and Slovak Tatra Mts are presented, most of them found recently, but a few also discovered during revision of old material collected by Z. Tobolewski. The ecology and chemistry of the taxon, and differences from related sorediate Lecanora species are briefly discussed.     

Southern isolation and northern long‐distance dispersal shaped the phylogeography of the widespread,but highly disjunct,European high mountain plant Artemisia eriantha (Asteraceae)

We investigated the range dynamics of Artemisia eriantha, a widespread, but rare, mountain plant with a highly disjunct distribution in the European Alpine System. We focused on testing the roles of vicariance and long‐distance dispersal in shaping the current distribution of the species. To this end, we collected AFLP and plastid DNA sequence data for 17 populations covering the entire distributional range of the species. Strong phylogeographical structure was found in both datasets. AFLP data suggested that almost all populations were genetically strongly differentiated, with 58% of the overall genetic variation partitioned among populations. Bayesian clustering identified five groups of populations: Balkans, Pyrenees, Central Apennines, one southwestern Alpine population and a Widespread cluster (eastern Pyrenees, Alps, Carpathians). Major groups were supported by neighbor‐joining and NeighbourNet analyses. Fourteen plastid haplotypes were found constituting five strongly distinct lineages: Alps plus Pyrenees, Apennines, Balkans, southern Carpathians, and a Widespread group (eastern Pyrenees, northern Carpathians, Mt. Olympus). Plastid DNA data suggested that A. eriantha colonized the European Alpine System in a westward direction. Although, in southern Europe, vicariant differentiation among the Iberian, Italian and Balkan Peninsulas predominated, thus highlighting their importance as glacial refugia for alpine species, in temperate mountain ranges, long‐distance dispersal prevailed. This study emphasizes that currently highly disjunct distributions can be shaped by both vicariance and long‐distance dispersal, although their relative importance may be geographically structured along, for instance, latitude, as in A. eriantha. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 214–226.     

Genetic structure of Hypochaeris uniflora (Asteraceae) suggests vicariance in the Carpathians and rapid post-glacial colonization of the Alps from an eastern Alpine refugium

Aim The range of the subalpine species Hypochaeris uniflora covers the Alps, Carpathians and Sudetes Mountains. Whilst the genetic structure and post‐glacial history of many high‐mountain plant taxa of the Alps is relatively well documented, the Carpathian populations have often been neglected in phylogeographical studies. The aim of the present study is to compare the genetic variation of the species in two major European mountain systems – the Alps and the Carpathians. Location Alps and Carpathians. Methods The genetic variation of 77 populations, each consisting of three plants, was studied using amplified fragment length polymorphism (AFLP). Results Neighbour joining and principal coordinate analyses revealed three well‐supported phylogeographical groups of populations corresponding to three disjunct geographical regions – the Alps and the western and south‐eastern Carpathians. Moreover, two further clusters could be distinguished within the latter mountain range, one consisting of populations from the eastern Carpathians and the second consisting of populations from the southern Carpathians. Populations from the Apuseni Mountains had an intermediate position between the eastern and southern Carpathians. The genetic clustering of populations into four groups was also supported by an analysis of molecular variance, which showed that most genetic variation (almost 46%) was found among these four groups. By far the highest within‐population variation was found in the eastern Carpathians, followed by populations from the southern and western Carpathians. Generally, the populations from the Alps were considerably less variable and displayed substantially fewer region‐diagnostic markers than those from the south‐eastern Carpathians. Although no clear geographical structure was found within the Alps, based on neighbour joining or principal coordinate analyses, some trends were obvious: populations from the easternmost part were genetically more variable and, together with those from the south‐western part, exhibited a higher proportion of rare AFLP fragments than populations in other areas. Moreover, the total number of AFLP fragments per population, the percentage of polymorphic loci and the proportion of rare AFLP fragments significantly decreased from east to west. Main conclusions Deep infraspecific phylogeographical gaps between the populations from the Alps and the western and south‐eastern Carpathians suggest the survival of H. uniflora in three separate refugia during the last glaciation. Our AFLP data provide molecular evidence for a long‐term geographical disjunction between the eastern and western Carpathians, previously suggested from the floristic composition at the end of 19th century. It is likely that Alpine populations survived the Last Glacial in the eastern part of the Alps, from where they rapidly colonized the rest of the Alps after the ice sheet retreated. Multiple founder effects may explain a gradual loss of genetic variation during westward colonization of the Alps.     

Phylogeography of a subalpine tall‐herb Ranunculus platanifolius (Ranunculaceae) reveals two main genetic lineages in the European mountains

A phylogeographical analysis of Ranunculus platanifolius, a typical European subalpine tall‐herb species, indicates the existence of two main genetic lineages based on amplified fragment length polymorphism (AFLP) markers. One group comprises populations from the Balkan Peninsula and the south‐eastern Carpathians and the other includes the remaining part of the range of the species, encompassing the western Carpathians, Sudetes, Alps, Pyrenees and Scandinavia. The main phylogeographical break observed in this species runs across the Carpathians and separates the main parts of this range (western and south‐eastern Carpathians), supporting a distinct glacial history of populations in these areas. The high genetic similarity of the Balkan Peninsula and south‐eastern Carpathian populations could indicate a common glacial refugium for these contemporarily isolated areas of species distribution. The western and northern part of the species range displays an additional weak differentiation into regional phylogeographical groups, which could have been shaped by isolation in glacial refugia or even by a postglacial isolation. The observed weak phylogeographical structure could also be linked with ecological requirements, allowing survival along streams in relatively low, forested mountain ranges. © 2013 The Linnean Society of London     

Taxonomy of theHieracium alpinum group in the sudeten Mts., the West and the Ukrainian East Carpathians

A taxonomic revision of theHieracium alpinum group (sensu Flora Europaea) in the Sudeten Mts., the West and the Ukrainian East Carpathians is provided. Six species are distinguished in the area studied, viz.Hieracium alpinum, H. halleri, H. augusti-bayeri, H. melanocephalum, H. tubulosum, andH. schustleri. H. alpinum occurs throughout the mountain ranges studied, three other taxa are endemic to the Sudeten Mts. (H. melanocephalum, H. tubulosum, H. schustleri), one is confined to the West Carpathians (H. halleri, in addition to the Alps) and one is endemic to the Ukrainian East Carpathians (H. augusti-bayeri). A diploid cytotype (2n=18) was ascertained inH. alpinum from the Ukrainian East Carpathians and the same chromosome number was found forH. augusti-bayeri. An agamospermous mode of reproduction was confirmed for the triploid cytotype ofH. alpinum, the triploidH. melanocephalum andH. halleri and the tetraploidsH. tubulosum andH. schustleri; the diploid taxa were found to be sexual. Pollen production in diploid taxa is high and pollen grains are homogeneous in size; triploid species, as well as tetraploidH. tubulosum, do not produce polllen; tetraploidH. schustleri has pollen grains of variable size. Data on the ecology and distribution of the species are also given.     

Differentiation and speciation in mountain streams: a case study in the caddisfly Rhyacophila aquitanica (Trichoptera)

Few studies have analysed the biogeography of mountain aquatic organisms, although this habitat provides stable conditions in which many species survived Pleistocene climatic oscillations, usually in the geographical vicinity of their present distribution ranges. The mountain caddisfly Rhyacophila aquitanica was selected as a model organism for this habitat type. Morphological measurements of genitalia and external characters of male individuals were obtained from almost the entire range of distribution of the species. Morphometric results were analysed by cluster analysis and multivariate statistics. Important differences were discovered among three population groups of R. aquitanica inhabiting different European mountain ranges: (i) mountain ranges north‐west of the Alps (Massif Central, Vosges, Schwarzwald and Fribourg); (ii) the southern Alps (Lombardia and Carinthia); and (iii) the western part of the southern Carpathians. This divergence suggests a long‐term isolation among these groups, which presumably took place long before the last Pleistocene glaciation, with no secondary contact among these populations. The differentiation centres of the southern Alps and Carpathian groups may have been mostly homotopic to their actual ranges, whereas the western group must have been distributed in the areas west or north‐west of the Alps with secondary expansions and disjunctions.     

Hieracium vierhapperi (Asteraceae) a new species to the Carpathians, with some remarks on its origin

Hieracium vierhapperi (Zahn) Szeląg, known so far only from the Alps, was discovered in the Nízke Tatry Mts in Slovakia, as a new species to the Carpathians. Diagnostic characters, illustration and distribution as well as ecology of H. vierhapperi in the Nízke Tatry Mts are given. A key to distinguish H. vierhapperi from the morphologically related species is added. The Carpathian plants are tetraploid (2n = 36) and reproduce apomictically. The origin of H. sect. Cernua R. Uechtr in the Western Carpathians is briefly discussed.     

Quantitative phytogeography of the Italian Beech Forests

This paper presents a numerical analysis of the distribution patterns in Europe and adjoining regions of 242 vascular plant species occurring in the Italian beech forests. The classification of a matrix of species and of 531 Operational Geographic Units (OGUs) led to recognition of 15 different phytogeographic elements (chorotypes). The joint distribution of the species belonging to each chorotype is shown by a chorogram, which is a geographic map obtained by computer processing of the distributional data. Some of the chorograms show the main distributional centers for the beechwood flora in southern Europe: northwestern Balkan Peninsula and eastern Alps, southern Balkan Peninsula, Maritime Alps, northern Apennines, southern Apennines. Only 20% of the species are limited to narrow areas in southern Europe, and were not able to expand considerably their ranges in postglacial times. Migration from the refugia and colonization of vast areas in central and northern Europe led to intensive speciation phenomena, occurring chiefly through the formation of neopolyploid species. Several south European, narrow-ranging species, can be considered as palaeopolyploids with relict character. There is a good relationship between distribution and ecology of the chorotypes.Abbreviations OGU Operational Geographic Unit - OGS Operational Geographic Set - OCS Operational Character Set     

Historical divergence vs. contemporary gene flow: evolutionary history of the calcicole Ranunculus alpestris group (Ranunculaceae) in the European Alps and the Carpathians

Although many species have similar total distributional ranges, they might be restricted to very different habitats and might have different phylogeographical histories. In the European Alps, our excellent knowledge of the evolutionary history of silicate‐dwelling (silicicole) plants is contrasted by a virtual lack of data from limestone‐dwelling (calcicole) plants. These two categories exhibit fundamentally different distribution patterns within the Alps and are expected to differ strongly with respect to their glacial history. The calcicole Ranunculus alpestris group comprises three diploid species of alpine habitats. Ranunculus alpestris s. str. is distributed over the southern European mountain system, while R. bilobus and R. traunfellneri are southern Alpine narrow endemics. To explore their phylogenetic relationships and phylogeographical history, we investigated the correlation between information given by nuclear and chloroplast DNA data. Analyses of amplified fragment length polymorphism fingerprints and matK sequences gave incongruent results, indicative for reticulate evolution. Our data highlight historical episodes of range fragmentation and expansion, occasional long‐distance dispersal and on‐going gene flow as important processes shaping the genetic structure of the group. Genetic divergence, expressed as a rarity index (‘frequency‐down‐weighted marker values’) seems a better indicator of historical processes than patterns of genetic diversity, which rather mirror contemporary processes as connectivity of populations and population sizes. Three phylogeographical subgroups have been found within the R. alpestris group, neither following taxonomy nor geography. Genetic heterogeneity in the Southern Alps contrasts with Northern Alpine uniformity. The Carpathians have been stepwise‐colonised from the Eastern Alpine lineage, resulting in a marked diversity loss in the Southern Carpathians. The main divergence within the group, separating the ancestor of the two endemic species from R. alpestris s. str., predates the Quaternary. Therefore, range shifts produced by palaeoclimatic oscillations seem to have acted on the genetic structure of R. alpestris group on a more regional level, e.g. triggering an allopatric separation of R. traunfellneri from R. bilobus.     

Higher genetic diversity in recolonized areas than in refugia of Alnus glutinosa triggered by continent‐wide lineage admixture

Genetic admixture is supposed to be an important trigger of species expansions because it can create the potential for selection of genotypes suitable for new climatic conditions. Up until now, however, no continent‐wide population genetic study has performed a detailed reconstruction of admixture events during natural species expansions. To fill this gap, we analysed the postglacial history of Alnus glutinosa, a keystone species of European swamp habitats, across its entire distribution range using two molecular markers, cpDNA and nuclear microsatellites. CpDNA revealed multiple southern refugia located in the Iberian, Apennine, Balkan and Anatolian Peninsulas, Corsica and North Africa. Analysis of microsatellites variation revealed three main directions of postglacial expansion: (i) from the northern part of the Iberian Peninsula to Western and Central Europe and subsequently to the British Isles, (ii) from the Apennine Peninsula to the Alps and (iii) from the eastern part of the Balkan Peninsula to the Carpathians followed by expansion towards the Northern European plains. This challenges the classical paradigm that most European populations originated from refugial areas in the Carpathians. It has been shown that colonizing lineages have met several times and formed secondary contact zones with unexpectedly high population genetic diversity in Central Europe and Scandinavia. On the contrary, limited genetic admixture in southern refugial areas of A. glutinosa renders rear‐edge populations in the Mediterranean region more vulnerable to extinction due to climate change.     

Quaternary history of the European roe deer Capreolus capreolus

• 1 The European roe deer Capreolus capreolus is a typical faunal element of the Holocene. It was already present in Europe at least 600 000 years ago and it has been known from both glacial and interglacial phases since then. With nearly 3000 fossil and subfossil records, it is one of the most frequent mammals in the Late Quaternary.
• 2 During the Middle and Late Weichselian Pleniglacial, the distribution of the roe deer was not restricted to the Mediterranean peninsulas but repeatedly reached regions of central Europe. In contrast to that, roe deer records from the Last Glacial Maximum (LGM, 21.0–14.5 ka ¹⁴C BP) are largely confined to the Mediterranean peninsulas – with the exception of south‐western France and the surroundings of the Carpathians where several records attest to its occurrence during the LGM.
• 3 During the Greenland Interstadial 1 (12.5–10.8 ka ¹⁴C BP), the species' distribution extended further north and the roe deer appeared north of the Alps and reached regions of central Germany. This seems to be correlated with the abrupt change to more favourable environmental conditions during this period. It is very likely that the roe deer disappeared north of the Alps during the Younger Dryas cooling (10.8–10.0 ka¹⁴C BP). The northern regions of the central European lowlands were recolonized by roe deer during the late Preboreal 9.7–9.5 ka ¹⁴C BP for the first time since the Weichselian Glacial.
• 4 The combined pattern of genetic data and fossil records of European roe deer suggests several regions in the Iberian peninsula, southern France, Italy and the Balkans as well as in the Carpathians and/or eastern Europe as glacial refugia. It further suggests that C. capreolus might have recolonized most parts of central‐northern Europe out of one or more eastern European (not Balkan) and/or Carpathian refugia. This recolonization wave might have blocked immigration from the traditional Mediterranean areas.

     

Morphological and genetic diversity within Pilosella hoppeana aggr. (Asteraceae) in Italy and taxonomic implications

Morphological variation, ploidy level and genetic diversity have been studied on 10 populations of the Pilosella hoppeana aggr. from the Alps, Abruzzo, Calabria and Sicily. Chromosome counts showed that the plants from Abruzzo and those from Sicily are tetraploid (2n = 36); they are assigned to P. hoppeana subsp. macrantha. The plants from the Alps (P. hoppeana subsp. hoppeana) and those from Calabria are diploid. The Calabrian populations, previously included in P. hoppeana subsp. macrantha, are shown to belong to a separate species, P. leucopsilon. The principal component analysis, based on 25 morphological characters, allowed distinguishing clearly four groups. An allozyme study using 10 enzyme systems revealed 7 polymorphic loci with a total of 20 alleles, some of them exclusive at regional level, others shared between populations showing similar morphological features. The genetic differentiation between populations was relatively high. The obtained dendrogram supports recognition of the morphologically defined taxa.     

Variation in the chloroplast DNA of Swiss stone pine (Pinus cembra L.) reflects contrasting post-glacial history of populations from the Carpathians and the Alps

Aim To characterize the genetic structure and diversity of Pinus cembra L. populations native to two disjunct geographical areas, the Alps and the Carpathians, and to evaluate the rate of genetic differentiation among populations. Location The Swiss Alps and the Carpathians. Methods We screened 28 populations at three paternally inherited chloroplast simple sequence repeats (cpSSRs) for length variation in their mononucleotide repeats. Statistical analysis assessed haplotypic variation and fixation indices. Hierarchical analysis of molecular variance (AMOVA), Mantel test, spatial analysis of molecular variance (SAMOVA) and barrier analyses were applied to evaluate the geographical partitioning of genetic diversity across the species’ range. Results Haplotypic diversity was generally high throughout the natural range of P. cembra, with the mean value substantially higher in the Carpathians (H = 0.53) than in the Alps (H = 0.35). The isolated Carpathian populations showed the highest haplotype diversity among the populations originating from the High Tatras (Velka Studena Dolina) and South Carpathians (Retezat Mountains). AMOVA revealed that only 3% of the total genetic variation derived from genetic differentiation between the two mountain ranges. Differentiation among Carpathian populations was higher (F_ST = 0.19) than among Alpine populations (F_ST = 0.04). Low, but significant, correlation was found between the geographical and genetic distances among pairs of populations (r = 0.286, P < 0.001). SAMOVA results revealed no evident geographical structure of populations. barrier analysis showed the strongest differentiation in the eastern part of the species’ range, i.e. in the Carpathians. Main conclusions The populations of P. cembra within the two parts of the species’ range still share many cpDNA haplotypes, suggesting a common gene pool conserved from a previously large, continuous distribution range. Carpathian populations have maintained high haplotypic variation, even higher than Alpine populations, despite their small population sizes and spatial isolation. Based on our results, we emphasize the importance of the Carpathian populations of Swiss stone pine for conservation. These populations comprise private haplotypes and they may represent a particular legacy of the species’ evolutionary history.     

Polyphyletic Alyssum cuneifolium (Brassicaceae) revisited: Morphological and genome size differentiation of recently recognized allopatric taxa

Alyssum cuneifolium has been recognized as a perennial alpine species growing in five isolated European mountain ranges: the Pyrenees, Western Alps, Apennines, Pirin Mts and Mt Smolikas. Recent molecular systematic studies revealed that the disjunct populations from distant mountains are not closely related and belong to five independent species: A. cacuminum (Spain, Pyrenees), A. cuneifolium (Italy, Apennines), A. flexicaule (France, Western Alps), A. pirinicum (Bulgaria, Pirin Mts), and A. spruneri (Greece, Mt Smolikas). The present study brings the thorough morphometric analysis of the segregated taxa. We found minor morphological differences between them. Whereas A. pirinicum can be clearly distinguished, the other taxa are recognizable only at the level of population means of investigated characters. The morphological similarity of these distantly related species is obviously the result of adaptation to similar high‐alpine scree habitats. It is not clear, however, whether this adaptation is environmentally controlled or whether it is also genetically fixed and whether it reflects parallel evolution towards similar morphotypes. The observed morphological patterns and their assumed correlation with environmental factors are discussed using examples from other Alyssum taxa. Three different ploidy levels have been reported for the species under study. In the present article, we examine variation in relative nuclear genome size. The Alpine and Pyrenean species have larger relative monoploid genome sizes than the Apennine and Balkan ones, probably reflecting the evolutionary history of the group. A nomenclatural account of the study species is presented, and lectotypes of A. cuneifolium and of two other names are selected.     

Cochlearia macrorrhiza (Brassicaceae): A bridging species between Cochlearia taxa from the Eastern Alps and the Carpathians?

Cochlearia macrorrhiza is one of the most highly endangered species in Central Europe and less than five individuals survived at its natural stand in a lowland area between the Eastern Alps and the Carpathians. Amplified fragment length polymorphisms (AFLPs) confirmed the status of C. macrorrhiza as a distinct taxon. Lowland C. macrorrhiza does not bridge the distribution of montainous and alpine Cochlearia species from the Eastern Alps and the Carpathians genetically, and C. macrorrhiza represents a separate lineage which evolved from diploid Cochlearia as C. excelsa in East Austrian high alpine regions did. Another species considered in this study, the Romanian C. borzaeana is more closely related to C. tatrae from the High Tatra mountains than to C. pyrenaica from Slovakia or Austria and the AFLP results suggest a single origin of alpine 2n=42 taxa. Genetic differentiation within and between populations is highly structured geographically, and the AFLP data favour a former widespread distribution of C. pyrenaica in mountainous regions and a parallel evolution of high alpine taxa in the Eastern Alps and the Carpathians, respectively.     

Phylogeography and cryptic variation within the Lacerta viridis complex (Lacertidae, Reptilia)

It is well known that the current genetic pattern of many European species has been highly influenced by climatic changes during the Pleistocene. While there are many well known vertebrate examples, knowledge about squamate reptiles is sparse. To obtain more data, a range‐wide sampling of Lacerta viridis was conducted and phylogenetic relations within the L. viridis complex were analysed using an mtDNA fragment encompassing part of cytochrome b, the adjacent tRNA genes and the noncoding control region. Most genetic divergence was found in the south of the distribution range. The Carpathian Basin and the regions north of the Carpathians and Alps are inhabited by the same mitochondrial lineage, corresponding to Lacerta viridis viridis. Three distinct lineages occurred in the south‐eastern Balkans — corresponding to L. v. viridis, L. v. meridionalis, L. v. guentherpetersi— as well as a fourth lineage for which no subspecies name is available. This distribution pattern suggests a rapid range expansion of L. v. viridis after the Holocene warming, leading to a colonization of the northern part of the species range. An unexpected finding was that a highly distinct genetic lineage occurs along the western Balkan coast. Phylogenetic analyses (Bayesian, maximum likelihood, maximum parsimony) suggested that this west Balkan lineage could represent the sister taxon of Lacerta bilineata. Due to the morphological similarity of taxa within the L. viridis complex this cryptic taxon was previously assigned to L. v. viridis. The distribution pattern of several parapatric, in part highly, distinct genetic lineages suggested the existence of several refuges in close proximity on the southern Balkans. Within L. bilineata sensu stricto a generally similar pattern emerged, with a high genetic diversity on the Apennine peninsula, arguing for two distinct refuges there, and a low genetic diversity in the northern part of the range. Close to the south‐eastern Alps, three distinct lineages (L. b. bilineata, L. v. viridis, west Balkan taxon) occurred within close proximity. We suggest that the west Balkan lineage represents an early offshoot of L. bilineata that was isolated during a previous Pleistocene glacial from the more western L. bilineata populations, which survived in refuges on the Apennine peninsula.     

Post-glacial history of the dominant alpine sedge Carex curvula in the European Alpine System inferred from nuclear and chloroplast markers

The alpine sedge Carex curvula ssp. curvula is a clonal, dominant graminoid found in the European Alps, the Carpathians, the Pyrenees and in some of the Balkan Mountains. It is a late-successional species of acidophilous alpine meadows that occurs on sites that were covered by ice during the last glacial maximum (LGM). By applying the amplified fragment length polymorphism (AFLP) fingerprinting and chloroplast DNA (cpDNA) sequencing, we attempted to identify the recolonization routes followed by the species after the last ice retreat. We relied on the genetic diversity of 37 populations covering the entire distributional range of the species. As a wind-pollinated species, C. curvula is characterized by a low level of population genetic differentiation. Nuclear and chloroplast data both support the hypothesis of a long-term separation of Eastern (Balkans and Carpathians) and Western (Alps and Pyrenees) lineages. In the Alps, a continuum of genetic depauperation from the east to the west may be related to a recolonization wave originating in the eastern-most parts of the chain, where the main glacial refugium was likely located. The Pyrenean populations are nested within the western Alps group and show a low level of genetic diversity, probably due to recent long-distance colonization. In contrast to the Alps, we found no phylogeographical structure in the Carpathians. The combination of reduced ice extension during the Würm period and the presence of large areas of siliceous substrate at suitable elevation suggest that in contrast to populations in the Alps, the species in the Carpathians underwent a local vertical migration rather than extinction and recolonization over long distance.