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Examples of traces obtained with one ITS fragment (Dmac). The autotetraploid Dactylorhiza maculata generally displays a 72-bp long fragment and the diploid D. incarnata an 80-bp long fragment. Dactylorhiza occidentalis (Ireland), D. sphagnicola (northwestern Europe) and D. elata (southwestern Europe and northwestern Africa) are all allotetraploids formed by hybridization between D. maculata (the maternal parent) and D. incarnata. Both parental alleles are present in both D. occidentalis and D. sphagnicola, but the maternal allele is dominant in the former and the paternal allele is dominant in the latter. In contrast, the paternal allele has been lost from D. elata.
Source publication
Patterns of polyploid evolution in the taxonomically controversial Dactylorhiza incarnata/maculata groups were inferred genetically by analyzing 399 individuals from 177 localities for (1) four polymorphic plastid regions yielding aggregate haplotypes and (2) nuclear ribosomal ITS allele frequencies. Concordance between patterns observed in distrib...
Similar publications
Most of the species studied in this paper have previously been placed in either Pleurothallis or Lepanthes. However, at one time or another, members of the group have also been placed in the genera Andinia, Brachycladium, Lueranthos, Masdevalliantha, Neooreophilus, Oreophilus, Penducella, Salpistele and Xenosia. Phylogenetic analyses of nuclear ITS...
Citations
... ex Rchb.) Soó (Fig. 1a), sibling allopolyploids (2n = 80) resulting from two independent and unidirectional polyploidisation events between D. incarnata and D. fuschii (the maternal parent) (Brandrud et al., 2020;Pillon et al., 2007). Typically, D. majalis is larger than D. traunsteineri, has more flowers per inflorescence and broader leaves (Fig. 1a). ...
In addition to demographic and dispersal constraints, a complex interplay of biotic and abiotic factors shapes the distribution of taxa across landscapes, with each species adapting uniquely to the challenges and opportunities presented by its habitat. Plasticity, the capacity to dynamically adjust one's phenotype in response to environmental shifts, is a pivotal trait enabling species to exploit a wider niche space and withstand suboptimal conditions. This adaptability is particularly crucial for newly formed allopolyploid lineages seeking to establish themselves in diverse environments. The amalgamation of different parental genomes in such hybrids can enhance their plastic responses to varying habitats, yet the long term impacts of plasticity on allopolyploid establishment success remain elusive. Here we use ecologically divergent sibling allopolyploid marsh orchids (Dactylorhiza, Orchidaceae) in reciprocal transplantation experiments at two localities to gain insights into the drivers of ecological divergence and species persistence in the face of gene flow. We show that while consistent abiotic differences characterise the alternative environments, the great majority of gene expression differences between the sibling allopolyploids is plastic. Few genes exhibit fixed expression differences, suggesting that despite ecological divergence, plasticity may mediate gene flow between the sibling allopolyploids, thereby preventing the accumulation of genetically encoded expression differences. Extending our investigations to the rhizosphere, we uncover distinct fungal communities between the roots of the two sibling allopolyploids, consistent across the two localities. This finding suggests that both biotic and abiotic factors contribute to the distribution and delimitation of Dactylorhiza sibling allopolyploids. Altogether, our results suggest that plasticity can exert both diversifying and homogenising influences on the establishment of recurrently-formed allopolyploid species.
... incarnata, and D. fuchsii are presumed to be long-lived, self-compatible, perennial orchids that generally reproduce via seeds or occasionally through vegetative means Vakhrameeva et al., 2008). In Europe, the allotetraploid D. majalis complex repeatedly evolved through hybridization between two broadly defined diploid lineages (D. incarnata and D. fuchsii), inheriting their plastid genomes from D. fuchsii (Pillon et al., 2007). They typically produce a single inflorescence and flowers with short spurs (Naczk et al., 2018). ...
A large suite of floral signals, and environmental and biotic characteristics influence the behavior of pollinators, affecting the female success of food‐deceptive orchids. In this study, we examined the many factors shaping the reproductive output of three orchid taxa: Dactylorhiza majalis , D. incarnata var. incarnata , and D. fuchsii . We applied a statistical model to correlate female success (number of fruit sets) with individual characteristics (plant and inflorescence height, number of flowers, and spur length), number of pollinaria removed, flowering time, and density of floral units of co‐flowering rewarding plants. Our findings suggested that the broad spectrum of variations in Dactylorhiza's morphological traits, floral display, and flowering phenology within different environmental contexts has a significant impact on their reproductive success. The number of fruits increased with an increase in the number of pollinaria removed in the studied Dactylorhiza taxa. In contrast, a higher number of flowers per inflorescence and higher inflorescences in relation to individual height always decreased fruit set. We observed that low number of co‐flowering rewarding plants in populations could affect the Dactylorhiza reproductive output as magnets and competitor plants. The synchronization of flowering, or lack thereof, between Dactylorhiza and rewarding plants can limit reproductive success. This demonstrates that the food deception strategy is multidirectional, and reproductive output can vary considerably both spatially and temporally within the context of this strategy.
... It is plausible that inbred progeny harboring deleterious alleles are not eliminated during over-fertilization or early germination phases (Ortiz-Barney & Ackerman, 1999). Dactylorhiza majalis, an allotetrapolyploid relative to its diploid progenitors D. incarnata and D. fuchsii (Pillon et al., 2007), represents a complex taxonomic group that evolved through multiple and independent hybridization events. The genus's taxonomic complexity is likely attributable to its migration history during glaciations and Distribution of inbreeding depression (d) in fruit set, seed number per fruit, seed length, frequency of well-developed embryos in seeds, and proportion of in vitro asymbiotic seed germination of Dactylorhiza majalis, D. incarnata var. ...
Introduction
Inbreeding depression (ID) in food-deceptive plants have been reported previously, however, it has not been often proven that selfed seeds germinate better than outbred ones or that selfing affects ID. To resolved these issues, food-deceptive related Dactylorhiza majalis, D. incarnata var. incarnata and D. fuchsii orchids were investigated.
Methods
Hand pollination treatments and control pollination were conducted. Fruit set, number of seeds per fruit, seed length, number of well-developed seeds per fruit, and proportion of in vitro asymbiotic germination seeds, were analyzed in relation to inflorescence levels and used as fitness indicators for these orchids. The ID and pollen limitation were measured.
Results
The lowest ID (δ = −1.000) was in D. majalis, and present in combination with a high pollen limitation in its populations. D. fuchsii showed higher ID (δ = 0.366), and D. incarnata var. incarnata weak ID (δ = 0.065), although ID varied between its fitness components. The seed number per fruit differed significantly between the treatments and the inflorescence levels in treatments.
Discussion
This study emphasizes that the breeding system rather than the flower position on the inflorescence shaped the quality and quantity of reproductive output. The ID and its effect on germination of food-deceptive orchid seeds undoubtedly played an important role.
... (diploid only), the D. maculata agg. (comprising diploids and autopolyploids) and the D. majalis / traunsteineri complex, which includes allopolyploid derivatives of the previous two groups (Hedrén 2001;Pillon et al. 2007;Devos et al. 2005;Hedrén et al. 2008;Nordström and Hedrén 2009;Balao et al. 2016;Brandrud et al. 2020). ...
Effective protection of endangered species is often limited by taxonomic discrepancies across state borders. This is also the case of the Dactylorhiza maculata agg. in Central Europe, where one to three species and several infraspecific taxa are recognized in various countries. Based on an extensive analysis of morphological variation, ploidy levels, environmental traits and habitats of 64 populations in Central Europe and adjacent regions, we aimed to propose a unified taxonomic concept applicable throughout the study area. Multivariate analysis of morphological traits revealed continuous variation at the individual level and only minor differences between particular clusters of populations. Four DNA-ploidy levels were detected using flow cytometry. Diploids (2 n = 40) and tetraploids (2 n = 80) were the most abundant and usually formed single-cytotype populations whereas DNA-triploids and DNA-hexaploids occurred only sporadically as minority cytotypes. The inferred patterns of morphological and ploidy variation were not congruent with traditional taxonomic treatment regarding diploid D. fuchsii and tetraploid D. maculata as two species with several infraspecific taxa. Instead, all taxa analysed in the current study are best treated at the subspecies level within D. maculata s. lat. due to somewhat continuous morphological variation between morphotypes. A total of eight D. maculata subspecies may be recognized in Central Europe, of which one is newly described here as D. maculata subsp. arcana , subsp. nov. Some nomenclatural riddles have been resolved, and the threat status of the recognized taxa is discussed.
... They arose from independent, but unidirectional allopolyploidization between D. fuchsii (as maternal genome) and D. incarnata (Figure 1a;Brandrud et al., 2020;Pillon et al., 2007). With DIY ABC (Cornuet et al., 2014) and genome-wide RADseq data, the maximum age of the sibling allopolyploids has been estimated as c. 1730 generations for D. majalis and c. 920 generations for D. traunsteineri (Brandrud, 2019 (Balao et al., 2016). ...
... It occupies almost exclusively previously glaciated ranges, suggesting an origin around the last glacial cycle. However, its regional mosaic of plastid DNA variants, some not found in the present-day representatives of its diploid parents, could support a pre-last glacial origin also for D. traunsteineri Pillon et al., 2007). Since their origin, both allopolyploids have experienced a considerable increase in genome size, mainly driven by a putative tandem repeat (Eriksson et al., 2022). ...
... Although the sibling species D. majalis and D. traunsteineri arose from recent unidirectional allopolyploidization events (Figure 1a; Brandrud et al., 2020;Hawranek, 2021;Pillon et al., 2007) but the metabolic processes necessary to assimilate this form of N are different from a nitrate-based metabolism (Xu et al., 2012). In contrast to NO 3 − which is processed in the leaves, NH 4 + is metabolized directly in the roots, a process that requires sugars which have to be transported from leaves to roots. ...
Whole-genome duplication has shaped the evolution of angiosperms and other organisms, and is important for many crops. Structural reorganization of chromosomes and repatterning of gene expression are frequently observed in allopolyploids, with physiological and ecological consequences. Recurrent origins from different parental populations are widespread among polyploids, resulting in an array of lineages that provide excellent models to uncover mechanisms of adaptation to divergent environments in early phases of polyploid evolution. We integrate here transcriptomic and ecophysiological comparative studies to show that sibling allopolyploid marsh orchid species (Dactylorhiza, Orchidaceae) occur in different habitats (low nutrient fens vs. meadows with mesic soils) and are characterized by a complex suite of intertwined, pronounced ecophysiological differences between them. We uncover distinct features in leaf elemental chemistry, light-harvesting, photoprotection, nutrient transport and stomata activity of the two sibling allopolyploids, which appear to match their specific ecologies, in particular soil chemistry differences at their native sites. We argue that the phenotypic divergence between the sibling allopolyploids has a clear genetic basis, generating ecological barriers that maintain distinct, independent lineages, despite pervasive interspecific gene flow. This suggests that recurrent origins of polyploids bring about a long-term potential to trigger and maintain functional and ecological diversity in marsh orchids and other groups.
... Although Orchidaceae have been long seen as a model family for pre-zygotic barriers to hybridization, primarily due to documented or inferred pollinator specificity (Ackerman et al. 2023), a growing body of literature makes clear that reproductive barriers are often porous, and that hybridization plays an important role in the speciation of many orchid genera (e.g., Dactylorhiza Neck. ex Nevski (e.g., Pillon et al. 2007), Epidendrum (e.g., Pinheiro et al. ...
Spiranthes Rich. (Orchidaceae) is a commonly encountered but systematically and nomenclaturally challenging component of the North American orchid flora. Here, the evolutionary history and hybrid origin of the recently described S. sheviakii Hough and Young are critically examined. The available molecular data unambiguously support a hybrid origin of S. cernua (L.) Rich. × S. ochroleuca (Rydb.) Rydb. for S. sheviakii , the same parentage as the priority name S. × kapnosperia M.C. Pace. As hybrid formulas can have only one correct name, S. sheviakii is a synonym of S. × kapnosperia. It is likely that S. × kapnosperia evolved independently at least twice in at least two widely disjunct locations.
... Molecular work began using allozymes in the mid-1990s in both Edinburgh, Scotland and Uppsala, Sweden (Hedrén 1996a(Hedrén , 1996b(Hedrén , 1996c(Hedrén , 2001, closely followed by typological phylogenetic studies spanning the genus that employed nrITS sequences (Pridgeon et al. 1997;Bateman et al. 2003). The 2000s began with analyses based on nuclear AFLPs (Hedrén et al. 2001;De Hert et al. 2012) and later plastid RFLPs (Devos et al. 2006), generated in parallel with more intensively sampled studies based on a combination of nuclear and plastid microsatellites (Hedrén 2003;Hedrén et al. , 2011aPillon et al. 2007;Nordstrom & Hedrén 2007Stahlberg & Hedrén 2008, 2010Balao et al. 2016). During the 2010s, the repertoire of techniques successfully applied to the genus expanded further to include methylation-sensitive AFLPs (Paun et al. 2010(Paun et al. , 2011 and gene expression patterns (Paun et al. 2011;Balao et al. 2017). ...
... Evidence has progressively accumulated showing that each of the four allotetraploid species is derived from a member of the Dactylorhiza fuchsii-maculata alliance as seed-parent and the D. incarnata clade as pollen parent, and that the two parental clades are only moderately closely related (e.g. Hedrén 1996b; Pillon et al. 2007;Brandrud et al. 2020), having diverged an estimated 8 Myr ago (Brandrud 2019;Hawranek 2021). ...
... The Madeiran island endemic D. foliosa, a diploid more closely related to D. fuchsii than to D. incarnata (e.g. Pillon et al. 2007), maintained only one allele at each locus: the c allele for pgd, the a allele for pgi and, surprisingly, the b allele for pgm -an allele that is characteristic of D. incarnata rather than D. fuchsii. Multiple genetic lines with contrasting geographic origins investigated within three of these four cultivated species consistently yielded identical, species-specific results ( Table 2B). ...
The intensively studied Eurasian orchid genus Dactylorhiza has become a model system for exploring allopolyploid evolution, yet determining the optimal circumscriptions of, and most appropriate ranks for, its constituent taxa remain highly controversial topics. Here, novel allozyme data and detailed morphometric data for 16 Scottish marsh-orchid populations are interpreted in the context of recent DNA sequencing studies. Despite being derived from the same pair of parental species, the two allopolyploid species that currently occur in Scotland can reliably be distinguished using allozymes, haplotypes, ribotypes or sequences of nuclear genes. A modest range of diverse morphological characters are shown to distinguish the two molecularly-circumscribed species, but they have in the past been obscured by equivalent levels of infraspecific variation in characters rooted in anthocyanin pigments; these characters are better employed for distinguishing infraspecific taxa. Dactylorhiza francis-drucei (formerly D. traunsteinerioides ) is confirmed as being distinct from the continental D. traunsteineri/lapponica , probably originating through allopatric isolation once the continental lineage reached Britain. All Scottish populations are attributed to the comparatively small-flowered, anthocyanin-rich subsp. francis-drucei , which includes as a variety the former D. 'ebudensis' ; the less anthocyanin-rich subsp. traunsteinerioides is confined to Ireland, North Wales and northern England. In contrast with D. francis-drucei , only a minority of Scottish populations of D. purpurella are attributed to the anthocyanin-rich race, var. cambrensis . This species most likely originated through an allopolyploidy event that occurred comparatively recently within the British Isles, as it contains allozyme alleles distinctive of British rather than continental D. incarnata (its diploid pollen-parent). In contrast, the rare Scottish population of D. incarnata subsp. cruenta shares with its Irish counterparts a continental genotype, and is most likely a recent arrival in Scotland through long-distance dispersal. Among all European allotetraploid dactylorchids, D. purpurella is the species that most closely resembles D. incarnata , both molecularly and morphologically.
... 2n = 36, 42) [4,5]. The number of Dactylorhiza species varies depending on the authors [6][7][8][9]. Databases list from over 660 [10] to over 720 names in the genus [11]. Representatives of Dactylorhiza are difficult in determining species affiliation due to their high propensity for hybridization and morphological variability [12][13][14][15][16][17]. ...
... Disjunctive distribution and response to climate change can also play a significant role in shaping it, which is important in planning species conservation efforts. There is a lack of global genetic studies on Dactylorhiza; however, from larger or smaller scale studies, it is known that the genetic variation in Dactylorhiza representatives is not relatively high [8,11,12]. ...
A critical study of the herbarium material representing the orchid genus Dactylorhiza Necker ex Nevski in Kazakhstan was conducted in 2019–2020. The information on the species composition was clarified. Dactylorhiza fuchsii subsp. hebridensis (Wilmott) Soó and D. × kerneri (Soó) Soó were identified for the first time in the country. New taxa were noted for individual botanical and geographical areas. All taxa were presented in the list and annotated with studied herbarium materials from the Kazakhstan area. Based on the collected and available locations for the studied taxa, distribution modeling was carried out for the four taxa (D. incarnata, D. majalis subsp. baltica, D. salina, and D. umbrosa). Bioclimatic data for the present and future (2041–2060) based on four possible scenarios were used. The occurrence of Dactylorhiza representatives in Kazakhstan is threatened by global climate warming. It is likely that some of them may not occur in the country in the future (D. incarnata and D. majalis subsp. baltica), losing up to 99.87% of their modern range or their range may be significantly reduced (D. salina and D. umbrosa), losing up to 80.83% of their present distribution. It is worth considering global changes in planning conservation activities and identifying areas that may play a significant role in the functioning of the national flora in the future.
... Recent taxonomic research (e.g. Pillon et al. 2006& 2007a, Bateman & Denholm 2012, Brandrud et al. 2020, Bateman 2021 clarified at least some of the genetic boundaries (and when lucky: also some of the morphological ones!) between the main NW-European taxa and also revealed their origin and evolution. It is now generally accepted that two originally diploid lineages (D. maculata-group, as the 'female'-parent, and D. incarnata-group, as the 'male'-parent) are at the basis of all actual auto-or allotetraploid north-western European species. ...
... The second diploid line concerns the eurosiberion D. incarnata s.l., including some more regional subtaxa as D. incarnata subsp./var. incarnata, cruenta, pulchella, coccinea, ochroleuca, … In general, as a minimum minimorum four 'classic' allotetraploids are recognized at species level (Devos et al. 2007;Pillon et al. 2007a;Brandrud et al. 2020) in western Europe: D. majalis and D. praetermissa (both probably D. 'fuchsii' x incarnata), and D. elata and D. sphagnicola (both probably D. 'maculata' x incarnata), or, from another taxonomical point of view, as subspecies; resp. D. majalis subsp. ...
Abstract. Some 25 years after a previous overview of the orchid flora of the Westhoek nature reserve (De Panne), this publication presents a recent update of the situation in the Westhoek reserve and, in extension, the whole of the Flemish dunes (between Sangatte and Breskens). The most obvious trend is the (very) outspoken increase in the number of individuals and populations of most of the already present species. The causes are a changing climate (Anacamptis pyramidalis, Himantoglossum hircinum, Ophrys apifera, …), improved nature protection and, especially, active nature management (Epipactis palustris, Dactylorhiza incarnata, Herminium monorchis, …) and an improved hydrology. But on top of that we must, for some species, also mention the side effects of urbanization and industrialization. However, for species as Anacamptis morio or Liparis loeselii only very little progress could be observed and the possibilities of their recovery are discussed. Unfortunately, some of the most vulnerable and formerly present species (Anacamptis palustris, Spiranthes spiralis) even remain completely absent from the Flemish dunes. The text also treats the increasing taxonomical tangle of Dactylorhiza taxa, partly as a side effect of successful nature management and confronts data from international literature with the preliminary results of additional FCM-analysis. Finally, the avail and efficiency of the existing legislation on plant (and orchid) species protection in Flanders is discussed.
... Hedrén 1996) and later using candidate-gene sequencing (e.g. Pillon et al. 2007), confirmed these hypotheses, showing that most of the western European allotetraploids originated through hybridisation between the same pair of parental species, D. fuchsii (or, less often, its autopolyploid derivative, D. maculata) and D. incarnata. Moreover, D. fuchsii was reliably the 'mother' and D. incarnata the 'father' of the allopolyploids. ...
... Other team members believe that each independent successful allopolyploidy event constitutes a separate speciation eventeffectively a monophyletic bottleneckand that the allotetraploid lineages that result can, with care, be differentiated through subtle differences in morphology and ecological preference. They further argue that these differences among allopolyploids reflect their independent origins from at least subtly different ecotypes that are documented within each of the two parental species (Pillon et al. 2007;Bateman and Denholm 2012;Brandrud et al. 2020). Interestingly, contrasting spectra of allopolyploid taxa are concentrated on either side of the maximum extent of the last glaciation, the most recently evolved species occurring to the north of the boundary (Bateman 2011(Bateman , 2020Brandrud et al. 2020). ...
... This fact is most readily illustrated by considering levels of divergence in nrITS sequences evident within the three case studies. Distances from the crown-group node to the tips of terminal branches are 4-9 bp within Dactylorhiza section Dactylorhiza (Pillon et al. 2007), 1-5 bp within the Ophrys sphegodes complex (Devey et al. 2008), and 0-3 bp within Epipactis section Epipactis (Bateman et al. 2005;Tranchida-Lombardo et al. 2012). In these cases, at least, the problematic clades that are most open to accusations of being cryptic all combine broadly similar morphologies with molecular trees in which terminal branches are short relative to those subtending other species included in the analysis. ...
Cryptic species are organisms which look identical, but which represent distinct evolutionary lineages. They are an emerging trend in organismal biology across all groups, from flatworms, insects, amphibians, primates, to vascular plants. This book critically evaluates the phenomenon of cryptic species and demonstrates how they can play a valuable role in improving our understanding of evolution, in particular of morphological stasis. It also explores how the recognition of cryptic species is intrinsically linked to the so-called 'species problem', the lack of a unifying species concept in biology, and suggests alternative approaches. Bringing together a range of perspectives from practicing taxonomists, the book presents case studies of cryptic species across a range of animal and plant groups. It will be an invaluable text for all biologists interested in species and their delimitation, definition, and purpose, including undergraduate and graduate students and researchers.
