Population divergence in the amphicarpic species Amphicarpaea edgeworthii Benth. (Fabaceae): microsatellite markers and leaf morphology

Comparative analyses of the genetic differentiation in microsatellite markers ( F _ST) and leaf morphology characters ( Q _ST) of Amphicarpaea edgeworthii Benth. were conducted to gain insight into the roles of random processes and natural selection in the population divergence. Simple sequence repeat analyses on 498 individuals of 19 natural populations demonstrate that a significant genetic differentiation occurs among populations (mean F _ST = 0.578), and A. edgeworthii is a highly self-fertilized species (mean selfing rate s  = 0.989). The distribution pattern of genetic diversity in this species shows that central populations possess high genetic diversity (e.g. population WL with H _E = 0.673 and population JG with H _E = 0.663), whereas peripheral ones have a low H _E as in population JD (0.011). The morphological divergence of leaf shape was estimated by the elliptical Fourier analysis on the data from 11 natural and four common garden populations. Leaf morphology analyses indicate the morphological divergence does not show strong correlation with the genetic differentiation ( R  = 0.260, P  = 0.069). By comparing the 95% confidence interval of Q _ST with that of F _ST, Q _ST values for five out of 12 quantitative traits are significantly higher than the average F _ST value over eight microsatellite loci. The comparison of F _ST and Q _ST suggests that two kinds of traits can be driven by different evolutionary forces, and the population divergence in leaf morphology is shaped by local selections.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 505–516.     

Microsatellite data reveals weak population substructuring in Copadichromis sp.'virginalis kajose', a demersal cichlid from Lake Malawi, Africa

Small but significant differences were found in allele frequencies among five populations (overall F _ST estimate (θ)=0·004, P=0·006; overall R _ST estimate (RHO)=0·019, P <0·00001) of the demersal cichlid Copadichromis sp.'virginalis kajose', collected from five locations in Lake Malawi. Pairwise F _ST estimates revealed significant differences between the most southerly population (Cape Maclear), and the three most northerly populations (Mbamba Bay, Metangula and Chilola). Pairwise R _ST estimates also revealed significant differences between some populations, but no geographical pattern was discernible. There was no evidence of isolation by distance using either the shortest straight-line distance between samples, or the distance around the shoreline following a 50 m depth contour. F _ST estimates were considerably lower than found in previous studies on the mbuna (rock-dwelling species), but higher than those found in a study of three pelagic cichlid species from Lake Malawi. Substructuring in C. sp.'virginalis kajose' appears to be on a similar scale to the Atlantic cod.     

Comparison of quantitative and molecular genetic variation of native vs. invasive populations of purple loosestrife (Lythrum salicaria L., Lythraceae)

Study of adaptive evolutionary changes in populations of invasive species can be advanced through the joint application of quantitative and population genetic methods. Using purple loosestrife as a model system, we investigated the relative roles of natural selection, genetic drift and gene flow in the invasive process by contrasting phenotypical and neutral genetic differentiation among native European and invasive North American populations ( Q _ST −  F _ST analysis). Our results indicate that invasive and native populations harbour comparable levels of amplified fragment length polymorphism variation, a pattern consistent with multiple independent introductions from a diverse European gene pool. However, it was observed that the genetic variation reduced during subsequent invasion, perhaps by founder effects and genetic drift. Comparison of genetically based quantitative trait differentiation ( Q _ST) with its expectation under neutrality ( F _ST) revealed no evidence of disruptive selection ( Q _ST >  F _ST) or stabilizing selection ( Q _ST <  F _ST). One exception was found for only one trait (the number of stems) showing significant sign of stabilizing selection across all populations. This suggests that there are difficulties in distinguishing the effects of nonadaptive population processes and natural selection. Multiple introductions of purple loosestrife may have created a genetic mixture from diverse source populations and increased population genetic diversity, but its link to the adaptive differentiation of invasive North American populations needs further research.     

Genetic diversity and genetic structure of populations of Ranunculus japonicus Thunb. (Ranunculaceae)

Abstract In order to clarify the genetic diversity and population structure of Ranunculus japonicus , allozymic analysis was conducted on 60 populations in southwestern Japan. Considerable genetic variati ons were detected among the populations of R. japonicus . The genetic diversities within species ( H _es = 0.215) and within populations ( H _ep = 0.172) were slightly higher than those of other perennial herbs with widespread distribution and outcrossing plants. Significantly higher values of fixation index were detected in some populations, which might have arisen from restricted mating partners. The majority of genetic variation (approx. 80%) resided within a population and a moderate level of genetic differentiation ( G _ST = 0.203) was observed among populations. The F _ST value (0.203) suggests the existence of a substantial population structure in this species. The highly significant correlation between geographic distance and F _ST values indicates that isolation by distance has played an important role in the construction of the genetic structure of this species.     

Geographic patterns of genetic differentiation and plumage colour variation are different in the pied flycatcher (Ficedula hypoleuca)

The pied flycatcher is one of the most phenotypically variable bird species in Europe. The geographic variation in phenotypes has often been attributed to spatial variation in selection regimes that is associated with the presence or absence of the congeneric collared flycatcher. Spatial variation in phenotypes could however also be generated by spatially restricted gene flow and genetic drift. We examined the genetic population structure of pied flycatchers across the breeding range and applied the phenotypic Q _ST ( P _ST)– F _ST approach to detect indirect signals of divergent selection on dorsal plumage colouration in pied flycatcher males. Allelic frequencies at neutral markers were found to significantly differ among populations breeding in central and southern Europe whereas northerly breeding pied flycatchers were found to be one apparently panmictic group of individuals. Pairwise differences between phenotypic ( P _ST) and neutral genetic distances ( F _ST) were positively correlated after removing the most differentiated Spanish and Swiss populations from the analysis, suggesting that genetic drift may have contributed to the observed phenotypic differentiation in some parts of the pied flycatcher breeding range. Differentiation in dorsal plumage colouration however greatly exceeded that observed at neutral genetic markers, which indicates that the observed pattern of phenotypic differentiation is unlikely to be solely maintained by restricted gene flow and genetic drift.     

Subtle population structuring within a highly vagile marine invertebrate, the veined squid Loligo forbesi, demonstrated with microsatellite DNA markers

Microsatellite DNA markers were applied for the first time in a population genetic study of a cephalopod and compared with previous estimates of genetic differentiation obtained using allozyme and mitochondrial DNA (mtDNA) markers. Levels of genetic variation detected with microsatellites were much higher than found with previous markers (mean number of alleles per locus=10.6, mean expected heterozygosity ( H _E)=0.79; allozyme H _E=0.08; mtDNA restriction fragment length polymorphism (RFLP) H _E=0.16). In agreement with previous studies, microsatellites demonstrated genetic uniformity across the population occupying the European shelf seas of the North East Atlantic, and extreme genetic differentiation of the Azores population ( R _ST/ F _ST=0.252/0.245; allozyme F _ST=0.536; mtDNA F _ST=0.789). In contrast to other markers, microsatellites detected more subtle, and significant, levels of differentiation between the populations of the North East Atlantic offshore banks (Rockall and Faroes) and the shelf population ( R _ST=0.048 and 0.057). Breakdown of extensive gene flow among these populations is indicated, with hydrographic (water depth) and hydrodynamic (isolating current regimes) factors suggested as possible barriers to migration. The demonstration of genetic subdivision in an abundant, highly mobile marine invertebrate has implications for the interpretation of dispersal and population dynamics, and consequent management, of such a commercially exploited species. Relative levels of differentiation indicated by the three different marker systems, and the use of measures of differentiation (assuming different mutation models), are discussed.     

Ancestry and divergence of subtropical montane forest isolates: molecular biogeography of the genus Abies (Pinaceae) in southern México and Guatemala

The genus Abies has a complex history in southern México and Guatemala. In this region, four closely related species, Abies flinckii , A. guatemalensis , A. hickelii , and A. religiosa , are distributed in fragmented and isolated montane populations. Range-wide genetic variation was investigated across species using cytoplasmic DNA markers with contrasted inheritance. Variation at two maternally inherited mitochondrial DNA markers was low. All species shared two of the nine mitotypes detected, while the remaining seven mitochondrial DNA types were restricted to a few isolated stands. Mitochondrial genetic differentiation across taxa was high ( G _ST = 0.933), it was not related to the taxonomic identity ( amova ; P  > 0.05) of the populations, and it was not phylogeographically structured ( G _ST ≈  N _ST). In contrast, variation at three paternally inherited chloroplast DNA microsatellites was high. Chloroplast genetic differentiation was lower ( G _ST = 0.402; R _ST = 0.547) than for mitochondrial DNA, but it was significantly related to taxonomy ( amova ; P  < 0.001), and exhibited a significant phylogeographical structure ( G _ST <  R _ST). Different analyses of population structure indicated that A. flinckii was the most divergent taxon, while the remaining three species formed a relatively homogeneous group. However, a small number of the populations of these three taxa, all located at the limits of their respective ranges or in the Transverse Volcanic Belt, diverged from this main cluster. These trends suggest that the Mesoamerican Abies share a recent common ancestor and that their divergence and speciation is mainly driven by genetic drift and isolation during the warm interglacial periods.     

Widespread gene flow and high genetic variability in populations of water voles Arvicola terrestris in patchy habitats

Theory predicts that the impact of gene flow on the genetic structure of populations in patchy habitats depends on its scale and the demographic attributes of demes (e.g. local colony sizes and timing of reproduction), but empirical evidence is scarce. We inferred the impact of gene flow on genetic structure among populations of water voles Arvicola terrestris that differed in average colony sizes, population turnover and degree of patchiness. Colonies typically consisted of few reproducing adults and several juveniles. Twelve polymorphic microsatellite DNA loci were examined. Levels of individual genetic variability in all areas were high ( H _O= 0.69–0.78). Assignments of juveniles to parents revealed frequent dispersal over long distances. The populations showed negative F _IS values among juveniles, F _IS values around zero among adults, high F _ST values among colonies for juveniles, and moderate, often insignificant, F _ST values for parents. We inferred that excess heterozygosity within colonies reflected the few individuals dispersing from a large area to form discrete breeding colonies. Thus pre-breeding dispersal followed by rapid reproduction results in a seasonal increase in differentiation due to local family groups. Genetic variation was as high in low-density populations in patchy habitats as in populations in continuous habitats used for comparison. In contrast to most theoretical predictions, we found that populations living in patchy habitats can maintain high levels of genetic variability when only a few adults contribute to breeding in each colony, when the variance of reproductive success among colonies is likely to be low, and when dispersal between colonies exceeds nearest-neighbour distances.     

Population genetic structure of the butterfly Melitaea didyma (Nymphalidae) along a northern distribution range border

The population genetic structure of the butterfly Melitaea didyma was studied along the northern distribution range border in Central Germany by means of allozyme electrophoresis. Individuals were sampled from a total of 21 habitat patches from four regions, and two provinces. Sampling was designed to estimate local vs. regional differentiation. High levels of variability were found, H _e= 0.14–0.21. The mean expected sample heterozygosity from one region, Mosel, was significantly lower than from the Hammelburg region, H _e= 0.17 and 0.19, respectively. Two hierarchical levels of genetic differentiation were found. Within regions individuals sampled from different patches behaved as belonging to one population with high levels of gene flow (Hammelburg F _ST= 0.015, Mosel F _ST= 0.044), though local isolation barriers did create a substructuring of these populations. The inbreeding coefficients, F _IS, were constant over all sample levels, suggesting a similar distribution of habitat patches within regions. Between regions gene flow was limited. An isolation by distance analysis indicated that the hierarchical structure, at the provincial level, may be breaking down due to isolation of regional populations. A more general observation was that the sampling design may greatly have influenced the estimation of genetic differentiation. Depending on which samples were included, overall F _ST estimates ranged from 0.059–0.090.     

Microsatellite analysis of genetic population structure in an endangered salmonid: the coastal cutthroat trout (Oncorhynchus clarki clarki)

The genetic population structure of coastal cutthroat trout ( Oncorhynchus clarki clarki ) in Washington state was investigated by analysis of variation in allele frequencies at six highly polymorphic microsatellite loci for 13 anadromous populations, along with one outgroup population from the Yellowstone subspecies ( O. clarki bouvieri) (mean heterozygosity = 67%; average number of alleles per locus = 24). Tests for genetic differentiation revealed highly significant differences in genotypic frequencies for pairwise comparisons between all populations within geographical regions and overall population subdivision was substantial ( F _ST = 0.121, R _ST = 0.093), with 44.6% and 55.4% of the among-population diversity being attributable to differences between streams ( F _SR = 0.054) and between regions ( F _RT = 0.067), respectively. Analysis of genetic distances and geographical distances did not support a simple model of isolation by distance for these populations. With one exception, neighbour-joining dendrograms from the Cavalli-Sforza and Edwards' chord distances and maximum likelihood algorithms clustered populations by physiogeographic region, although overall bootstrap support was relatively low (53%). Our results suggest that coastal cutthroat trout populations are ultimately structured genetically at the level of individual streams. It appears that the dynamic balance between gene flow and genetic drift in the subspecies favours a high degree of genetic differentiation and population subdivision with the simultaneous maintenance of high heterozygosity levels within local populations. Results are discussed in terms of coastal cutthroat trout ecology along with implications for the designation of evolutionarily significant units pursuant to the US Endangered Species Act of 1973 and analogous conservation units.     

Q ST MEETS THE G MATRIX: THE DIMENSIONALITY OF ADAPTIVE DIVERGENCE IN MULTIPLE CORRELATED QUANTITATIVE TRAITS

The Q _ST– F _ST comparison has become an increasingly common method for inferring adaptive quantitative trait divergence among populations. For cases in which there is divergence in multiple traits, most studies have applied the method by performing multiple univariate Q _ST– F _ST comparisons. However, because traits are often genetically correlated, such univariate analyses are likely to paint a simplified picture of adaptive divergence. Here we show how the multivariate analogue of Q _ST, F_STq, which accounts for genetic correlations among traits, can be used to supply a more detailed picture of multitrait divergence. We apply the method to naturally occurring genetic variation for a suite of sexually selected display traits in Drosophila serrata . The analyses suggest the operation of divergent multivariate selection that has influenced multiple independent axes of genetic variance in a sex-specific manner. Finally, we show how a comparison of the components of F_STq, the average within and among population genetic variance–covariance matrices, G_W and G_B, can be used as an additional test of the null expectation of neutral divergence, and allows for an investigation of whether natural populations have diverged along major or minor axes of genetic variance.     

Population genetic structure of wild rice Oryza glumaepatula distributed in the Amazon flood area influenced by its life-history traits

Wild plant species develop their own way of living to adapt to the specific environment of their habitats. Their life-history traits strongly affect the genetic structure of the population. The wild species Oryza glumaepatula Steud. growing in the Amazon basin seems to have characteristic life-history traits suited for the flood condition. At the vegetative growth stage, the culms frequently break at internodes. With no roots anchoring on the ground, plant bodies floating in the water move downriver by water current and wind. To examine the association between the life-history traits and genetic population structure of Amazonian O. glumaepatula , we analysed allozyme variability at 29 loci of 16 enzymes using 37 populations from five regions. Allozymes were not so variable (total gene diversity H _E = 0.044) compared with Asian wild rice, O. rufipogon Griff. The bottleneck effect and rare opportunity of interspecies gene flow may prevent the development of allozyme variability. Population genotypes tended to be differentiated among geographically isolated regions. Observed heterozygosities were much lower than expected heterozygosities, or gene diversity ( H _O = 0.003 for whole population) and F _IS over polymorphic loci was 0.931, indicating that O. glumaepatula has developed an inbreeding system. But, the intrapopulation gene diversity ( H _S) was higher than interpopulation gene diversity ( D _ST), as generally observed in outbreeding populations. The migration ability of O. glumaepatula makes long-distance seed dispersal possible. This might have led to frequent gene flow among populations.     

Scanning the genome for gene single nucleotide polymorphisms involved in adaptive population differentiation in white spruce

Conifers are characterized by a large genome size and a rapid decay of linkage disequilibrium, most often within gene limits. Genome scans based on noncoding markers are less likely to detect molecular adaptation linked to genes in these species. In this study, we assessed the effectiveness of a genome-wide single nucleotide polymorphism (SNP) scan focused on expressed genes in detecting local adaptation in a conifer species. Samples were collected from six natural populations of white spruce ( Picea glauca ) moderately differentiated for several quantitative characters. A total of 534 SNPs representing 345 expressed genes were analysed. Genes potentially under natural selection were identified by estimating the differentiation in SNP frequencies among populations ( F _ST) and identifying outliers, and by estimating local differentiation using a Bayesian approach. Both average expected heterozygosity and population differentiation estimates ( H _E = 0.270 and F _ST = 0.006) were comparable to those obtained with other genetic markers. Of all genes, 5.5% were identified as outliers with F _ST at the 95% confidence level, while 14% were identified as candidates for local adaptation with the Bayesian method. There was some overlap between the two gene sets. More than half of the candidate genes for local adaptation were specific to the warmest population, about 20% to the most arid population, and 15% to the coldest and most humid higher altitude population. These adaptive trends were consistent with the genes' putative functions and the divergence in quantitative traits noted among the populations. The results suggest that an approach separating the locus and population effects is useful to identify genes potentially under selection. These candidates are worth exploring in more details at the physiological and ecological levels.     

The distribution of random amplified polymorphic DNA (RAPD) diversity amongst populations of Isotoma petraea (Lobeliaceae)

RAPDs were generated from plants of six populations of Isotoma petraea F. Muell. The species occurs on rock outcrops in southern and western Australia, with populations exhibiting different breeding systems, including complete autogamy, varying levels of outbreeding and complex hybridity. Non-metric multidimensional scaling (nMDS) analysis of the random amplified polymorphic DNA (RAPD) data set clearly resolved all populations. The Pigeon Rock population, which is home to both complex hybrid and structural homozygote plants, was divided into those two groups by the nMDS analysis. There was little diversity in highly autogamous populations, but levels were higher in the outbred Yackeyackine population. All complex hybrid populations and plants possessed numerous genetic system-specific RAPDs, some of which were shown to be held in fixed heterozygosity. Estimating G _ST using RAPDs has been problematical due to their dominance, and analytical methods usually rely on knowledge of the selfing rate or assume Hardy–Weinberg equilibrium. This assumption does not hold when populations exhibit fixed heterozygosity, and an alternative method, Shannon's Index, was used to partition genetic diversity. The distribution of genetic diversity fit expectations for an inbreeding species, with most of the variation (87.5%) occurring between populations. This compares to an average RAPD-based G _ST of 59.6% for inbreeding species generally and 15.5% for outbreeding species.     

POPULATION STRUCTURE IN AN INSHORE CETACEAN REVEALED BY MICROSATELLITE AND mtDNA ANALYSIS: BOTTLENOSE DOLPHINS (TURSIOPS SP.) IN SHARK BAY, WESTERN AUSTRALIA

We examined population substructure of bottlenose dolphins ( Tursiops sp). in Shark Bay, Western Australia, using 10 highly polymorphic microsatellite loci, and mitochondrial DNA (mtDNA). For microsatellite analysis, 302 different animals were sampled from seven localities throughout the bay. Analysis of genetic differentiation between sampling localities showed a significant correlation between the number of migrants ( Nm ) calculated from F _ST, R _ST and private alleles, and distance between localities–a pattern of isolation-by-distance. For mtDNA, 220 individuals from all seven localities were sequenced for a 351 base pair fragment of the control region, resulting in eight haplotypes, with two distinct clusters of haplotypes. Values of F _ST and (φ)_ST for mtDNA yielded statistically significant differences, mostly between localities that were not adjacent to each other, suggesting female gene flow over a scale larger than the sampled localities. We also observed a significant correlation between the number of female migrants calculated from F _ST and φ_ST and the distance of sampling localities. Our results indicate that dispersal in female dolphins in Shark Bay is more restricted than that of males.     

Molecular and quantitative trait variation within and among populations of the intertidal copepod Tigriopus californicus

Abstract While molecular and quantitative trait variation may be theoretically correlated, empirical studies using both approaches frequently reveal discordant patterns, and these discrepancies can contribute to our understanding of evolutionary processes. Here, we assessed genetic variation in six populations of the copepod Tigriopus californicus. Molecular variation was estimated using five polymorphic microsatellite loci, and quantitative variation was measured using 22-life history and morphometric characters. Within populations, no correlation was found between the levels of molecular variation (heterozygosity) and quantitative variation (heritability). Between populations, quantitative subdivision ( Q _ST) was correlated with molecular subdivision when measured as F _ST but not when measured as R _ST. Unlike most taxa studied to date, the overall level of molecular subdivision exceeded the level of quantitative subdivision ( F _ST= 0.80, R_ST = 0.89, Q _ST = 0.30). Factors that could contribute to this pattern include stabilizing or fluctuating selection on quantitative traits or accelerated rates of molecular evolution.     

Small-Scale Fragmentation Effects on Local Genetic Diversity in Two Phyllostomid Bats with Different Dispersal Abilities in Panama

Habitat fragmentation is one of the greatest threats to biodiversity. Despite their importance for conservation, the genetic consequences of small-scale habitat fragmentation for bat populations are largely unknown. In this study, we linked genetic with ecological and demographic data to assess the effects of habitat fragmentation on two species of phyllostomid bats ( Uroderma bilobatum and Carollia perspicillata ) that differ in their dispersal abilities and demographic response to fragmentation. We hypothesized that population differentiation and the effect of habitat fragmentation on levels of genetic diversity will be a function of the species' mobility. We sequenced mtDNA from 232 bats caught on 11 islands in Gatún Lake, Panamá, isolated from the mainland for ca 90 yr, and in adjacent, continuous forest on the mainland. Populations of both species showed significant genetic differentiation ( F _ST). Consistent with our prediction, population subdivision was lower in the highly mobile U. bilobatum ( F _ST= 0.01) compared to the less vagile C. perspicillata ( F _ST= 0.06), and only the latter species showed a pattern indicative of isolation by distance and, in addition, an effect of fragmentation. Genetic erosion as a result of fragmentation was also only detectable in the less mobile species, C. perspicillata , where haplotype diversity was lower in island compared to mainland populations. Our results suggest that some Neotropical bat species are prone to loss of genetic variation in response to anthropogenic small-scale habitat fragmentation. In this context, our findings point toward mobility as a good predictor of a species' vulnerability to fragmentation and altered population genetic structure.     

Did Polyommatus icarus (Lepidoptera: Lycaenidae) have distinct glacial refugia in southern Europe? Evidence from population genetics

Pleistocene climatic oscillations strongly influenced the genetic composition of many species which are often divided into several genetic lineages. In this context, we studied the allozymes of a common and widely distributed butterfly, the common blue Polyommatus icarus, over a large part of Europe. The species had a rather high genetic diversity within populations with a strikingly high mean number of alleles per locus (2.98). In contrast, differentiation between populations was very low ( F _ST: 0.0187). Only a marginal trend of decline in genetic diversity from the south to the north was observed. Isolation-by-distance existed on a European scale ( r =  0.826), but not at a regional level. Regional differentiation between populations in western Germany was extremely low ( F _ST: 0.0041). It is probable that P. icarus was widely distributed in the Mediterranean region during the last ice age and expanded into central Europe in the postglacial period without major genetic erosion. Moderate present and past gene flow in an intact metapopulation structure may have occurred on local, regional and perhaps even continental scales.  © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 80 , 529–538.     

Allozyme Diversity in Populations of Cymbidium goeringii (Orchidaceae)

Abstract: Using 14 allozyme loci, we investigated levels of genetic diversity within populations, and degree of genetic divergence among 24 populations of Cymbidium goeringii (Orchidaceae) in Korea and Japan. Cymbidium goeringii maintains high levels of genetic diversity both at population (mean expected heterozygosity, H _e = 0.238) and species levels (0.260). Means of H _e found in 24 populations were not significantly different from each other. About 90 % of the total variation in the species is common to all populations (mean G _ST = 0.108). No unique allele was found in any population. The indirect estimate of gene flow based on the mean G _ST was high ( Nm = 2.06). Nei's genetic identities for pairs of populations had high values (mean = 0.974 [SD = 0.013]). The Mantel-Z test showed a significant correlation between genetic distance and geographic distance. However, the mean G _ST value between 17 populations in Korea and seven Japanese populations was relatively low (0.029), even though the land connection between the southern Korean peninsula and southern Japanese archipelagos has not existed since the middle Pleistocene. Large numbers of small seeds of C. goeringii might travel long distances by wind from populations to populations both in Korea and Japan, increasing genetic diversity within populations and maintaining low genetic differentiation among populations.     

Conservation Genetics of an Endangered Herb, Hanabusaya asiatica (Campanulaceae)

Abstract: Hanabusaya asiatica (Nakai) Nakai (Campanulaceae), a bee- pollinated, perennial herb, is restricted to the mountainous regions of the eastern-central Korean peninsula. Allozyme analyses for 348 individuals assessed the levels of genetic diversity for five populations. Spatial autocorrelation statistics were also used to examine the spatial distribution of allozyme polymorphisms. The species maintains high levels of allozyme diversity ( H _eS = 0.217) and it exhibits low allozyme differentiation among populations ( G _ST = 0.132) compared with other endemics (mean H _e = 0.096, G _ST = 0.248). There is an apparent pattern of isolation by distance among populations. These results suggest that H. asiatica is at a genetic equilibrium. A considerable deficit in numbers of heterozygotes suggests mating among relatives in populations. At least three populations of H. asiatica should be sampled or conserved to capture or maintain > 99 % of the genetic diversity in the species as a whole. Within local populations, individuals are distributed in a structured, isolation by distance, manner. Approximate genetic patch width in the populations of H. asiatica examined is 5 - 8 m. For conservation purposes, it is suggested that, in general, the sampling of H. asiatica should be conducted at intervals in order to efficiently sample the genetic diversity across an entire population.