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A new species of the firmoss from China, Huperzia crassifolia sp. nov., is described and illustrated based on morphological characters and molecular evidence. The new species resembles species associated with the H. javanica complex, in particular H. javanica based on leaf shape and serrations, but can be easily distinguished by elliptic lanceolate and thick coriaceous leaves, well differentiated seasonal constriction zones, and reflexed leaf margins when get dried. Phylogenomic reconstruction using whole chloroplast genome sequences recovered H. crassifolia as sister to H. sutchueniana and only distantly related to morphological similar species H. javanica, H. nanlingensis, and H. serrata. The genome size 2C = 17.2 pg indicated the new species to be a tetraploid, whereas diploid H. javanica had a genome size of 8.7 pg. Morphological characters, distribution, and conservation status of the new species are also presented.

Here, we describe a new species of Crotalaria L. discovered in Mengla County, Xishuangbanna Dai Autonomous Prefecture, Yunnan, China. The new species, Crotalaria menglaensis S.A.Rather, was confirmed by identifying diagnostic morphological characteristics, performing principal component analyses of phenotypic traits, and phylogenetic analyses based on nuclear ITS and plastid matK sequences. Phylogenetic analyses recovered the two accessions of the new species to be sister to C. bracteata Roxb. ex DC. In turn, these two species formed the sister clade to the two accessions of C. incana L. The morphometric analyses revealed that all three species were distinct, while the analyses of distinctive characters enabled unambiguous distinction of the new species by its growth habit, leaflets, flower structure and pod morphology. In contrast to the two related species, the new species is currently known only from ca. 100 mature individuals. Thus, this species is considered to be critically endangered.

Societal Impact Statement Hybridisation is an important evolutionary force in plants, but it can potentially lead to genetic swamping and extinction of one or both parental species. The threat of extinction is of particular concern if hybridisation occurs between native and introduced species, especially when the native is of national importance. The widespread occurrence of non‐native bluebells in the United Kingdom has raised concerns that the iconic native bluebell could be at risk due to extinction by hybridisation from introduced non‐native bluebells. This study determines the taxonomic identity of non‐natives and investigates the amount of hybridisation occurring in natural and semi‐natural UK bluebell populations. Summary The widespread occurrence of a non‐native bluebell taxon in the UK has raised concerns that the iconic native bluebell H. non‐scripta (Asparagaceae) could be at risk due to extinction by hybridisation from introduced non‐native congeners. Understanding the nature of this threat requires quantification of the extent of hybridisation between the native and non‐native taxa. An additional complication is taxonomic uncertainty regarding the identity of the non‐native bluebells in the United Kingdom that are colloquially referred to as the ‘Spanish’ bluebell (H. hispanica). We collected 501 bluebell samples from 56 populations in the United Kingdom (H. non‐scripta and non‐natives) and the Iberian Peninsula (H. hispanica). The samples were assayed for variation at 1871 nuclear and 17 plastid single nucleotide polymorphisms. Our genetic analyses demonstrated that non‐native bluebells in the United Kingdom are not H. hispanica but the hybrid between H. hispanica and H. non‐scripta. Moreover, they supported the hypothesis that Portugal is the country of origin of the first H. hispanica introductions to the United Kingdom. The frequency of hybrids was about 16%. Backcrosses between the (hybrid) non‐native bluebell and the native H. non‐scripta were primarily found in public parks. Of the sampled individuals for H. non‐scripta from natural habitats, only 2% showed evidence of introgression. Although hybridisation might be frequent in locations where non‐native bluebells have been introduced, we found no evidence of large‐scale introgression in natural H. non‐scripta populations. Therefore, our results do not support concerns of an ‘extinction by hybridisation’ scenario.

The genus Begonia has not only been recognised to be one of the mega-diverse plant genera but also as one found to comprise many undiscovered species. In particular, the increase of extensive field surveys in tropical regions of Southeast Asia has added to the discovery of many new species that are often found only in a few localities. In this study, the new taxon Begonia fimbristipula subsp. siamensis subsp. nov. from Thailand is described. The Thailand accessions are highly similar in their morphology to accessions of B. fimbristipula from southern China but differ in their tuber shape, peduncle trichomes, petiole trichomes and number of female tepals. The new taxon has been found only in the northern parts of Thailand occurring at elevations above 1,300 meters. The new findings not only contribute to our knowledge of the plant diversity of Thailand but provide also critical information contributing to the protection of this species. In China, this species is endangered which is of special concern given its utilisation as a medical herb in traditional Chinese medicine. Considering IUCN Red List Categories, the new subspecies is considered to be Vulnerable. The disjunct distribution of the two subspecies of B. fimbristipula encourages urgently needed comparative taxonomic studies across the Indo-Burma biodiversity hotspot.

The fossil fern species Cretacifilix fungiformis from mid-Cretaceous Kachin amber from Myanmar was previously assigned to eupolypod ferns for having sporangia with a vertical annulus and sporangial stalks 2–3 cells thick, along with monolete spores with a distinct perine. However, due to the insufficient documentation of character states and the unavailability of the holotype, the proposed affiliation of this fossil to derived families of eupolypods required further study. The recent discovery of additional leaf fragments of C. fungiformis from the same amber deposit enabled us to re-evaluate the relationships of this fossil taxon. Newly documented morphological evidence corroborated its placement within the eupolypod ferns. This was achieved by evaluating identifiable features present in the fossil species through an ancestral character state reconstruction utilizing a comprehensive, time-calibrated phylogeny of eupolypod ferns. Our character state reconstruction of extant eupolypod families and genera recovered morphological similarity of Cretacifilix to the closely related genera Arachniodes and Dryopteris, supporting an assignment of this fossil genus to the species-rich family Dryopteridaceae within the Polypodiineae.

A new species of the species-rich fern genus Lepisorus (Polypodiales, Polypodiaceae) has been found to occur in Shan state, Myanmar. Lepisorus medioximus is described based on morphological characters and phylogenetic evidence. Phylogenetic analyses showed that the specimens of L. medioximus formed a distinct clade nested in the Pseudovittaria clade. The morphological comparison demonstrated that the species is distinct from phylogenetically related species, namely L. elegans, L. contortus, and L. tosaensis, in the morphology of the rhizome scales, size, and shape of the lamina, position of sori, and paraphyses.

The genus Thylacopteris is a small, phylogenetically isolated genus belonging to the fern family Polypodiaceae. This study describes a new species, Thylacopteris minuta, based on collections obtained during field surveys of Shan State, Myanmar. This new species is distinct from other species of Thylacopteris in its small size and presence of sclerenchyma strands in the rhizome. This species is also distinct from the only other species of Thylacopteris with molecular data available, T. papillosa, in a plastid rbcL phylogeny of Polypodiaceae. This new discovery of Thylacopteris from Myanmar suggests that this genus is still overlooked in Southeast Asia.

Semiconductor nanowires are promising candidates for the realization of novel transistor concepts. Here, the authors demonstrate that electron mobility in strained coaxial nanowire heterostructures can be higher than in the corresponding bulk crystals.

Bacteria communities associated with plants have been given increasing consideration because they are arguably beneficial to their host plants. To understand the ecological and evolutionary impact of these mutualistic associations, it is important to explore the vast unknown territory of bacterial genomic diversity and their functional contributions associated with the major branches of the tree-of-life. Arguably, this aim can be achieved by profiling bacterial communities by applying high throughput sequencing approaches, besides establishing model plant organisms to test key predictions. This study utilized the Illumina Miseq reads of bacterial 16S rRNA sequences to determine the bacterial diversity associated with the endosphere of the leaves of the highly specialized rock spleenwort Asplenium delavayi (Aspleniaceae). By documenting the bacterial communities associated with ferns collected in natural occurrence and cultivation, this study discovered the most species-rich bacterial communities associated with terrestrial ferns reported until now. Despite the substantial variations of species diversity and composition among accessions, a set of 28 bacterial OTUs was found to be shared among all accessions. Functional analyses recovered evidence to support the predictions that changes in bacterial community compositions correspond to functional differentiation. Given the ease of cultivating this species, Asplenium delavayi is introduced here as a model organism to explore the ecological and evolutionary benefits created by mutualistic associations between bacteria and ferns.

Producing pulses in the mid-IR often requires bulky sources and has been inaccessible with compact and versatile quantum cascade lasers (QCLs). Here, the authors demonstrate actively mode-locked, mid-IR QCL operation at room temperature.

Our understanding of the flora of China has greatly improved during the last 100 years but effective management of the rich biodiversity and unique natural resources requires resolving the taxonomic limitations of existing treatments. Here, we focus on the epiphytic genus Scleroglossum with special emphasis on the occurrences in Hainan and Yunnan of mainland China. By combining fieldwork, herbarium studies, and DNA barcoding we test the hypothesis that this genus is represented by more than one species in China. Our integrative results show the Yunnan accessions are distinct from those in Hainan in both phenotypic and genotypic variation. The Yunnan accessions belong to S. pusillum, whereas the Hainan accessions represent a distinct species displaying the morphological characteristics of S. sulcatum. Genotypic evidence suggests the occurrence of cryptic diversity among accessions with the morphology of S. sulcatum. In summary, the study contributes to the crucial assessment of the plant diversity in Yunnan and illustrates the importance of integrating collection efforts and DNA barcoding approaches to enable effective assessment of the epiphytic diversity of Yunnan.

Designing core/shell nanowires with desired optoelectronic properties of III-V semiconductor alloys remains a challenge. Here, the authors report an engineering strategy to surmount strain-induced difficulties in the growth achieving highly strained cores with a sizeable change in their band gap.

The data in this article provide information about the species richness of each political unit in Myanmar and their preliminary conservation status. The dataset was compiled by gathering scattered data from different sources. The majority of the data were compiled from the authors’ collections and historical and recent floristic treatments. Online databases and herbarium specimens were additional resources used for data compilation. In total, 603 species were documented and species names were standardized in accordance with the International Plant Names Index and Pteridophyte Phylogeny Group. Species composition between political units was calculated using the minimum variance of the Jaccard's dissimilarity matrix. Conservation status for 558 pteridophyte species from Myanmar was evaluated based on the global occurrences and occurrences only in Myanmar, and species with less than three occurrences were excluded from the analysis. This dataset can be applied as the reference data for future taxonomic revisions, biodiversity assessments, and conservation planning. Moreover, the data can be used for global diversity assessment, broad-scale species distribution modeling and bioclimatic modeling. The data provided in this manuscript have been analyzed and discussed in Khine and Schneider [1].

The ongoing biodiversity crisis enforces the need of practical conservation plans based on robust estimates of the threats to local from regional biodiversity. Unfortunately, this protocol has been difficult to apply especially to species rich, but poorly explored nations such as Myanmar. Therefore, efforts to obtain the local assessments are urgently needed before having local vegetation reduced to small remnants. The current study aimed at the first evaluation of pteridophyte conservation status using the global occurrence data and assessment of the conservation gaps and priority regions.Diversity and priority indices such as species richness, compositions and conservation status for IUCN criterion B of 603 species were observed to define the regions and hotspots of Myanmar. Forty-five species of which were assigned to DD category having less than three occurrences. Indices were demonstrated in regional level of states and regions in Myanmar and local levels of 0.5-degree gridded cells.Species richness was highest in Kachin (389 species), followed by Shan (181 spp.), and Chin (127 spp.). The highest turnover was recorded of Ayeyarwady (0.91), Rakhine (0.91), and Magway (0.90). Seventeen percent of evaluated species was assigned into threatened categories. The value of pixels varied from 1 to 153 for species richness, 0.89 to 0.96 for species turnover rate and 1 to 31 for number of threatened species. The overlap between existing protected area and hotspots was 100% and 67% for above 95th and 90th percentile respectively.Attempts to raise the awareness of pteridophytes’ threat level and conservation priority regions have emerged for Myanmar. The conservation gaps and priority regions highlighted from this study are robust having an insight into the different diversity and conservation indices. However, ground data checking and extensive evaluation is recommended for Data Deficient species as most of these species are likely to be evaluated as threatened species. First evaluation of conservation status for pteridophyte contributes substantially to the conservation planning in Myanmar.

The European Spallation Source (ESS), which is under construction in Lund (Sweden), will be the leading and most brilliant neutron source and aims at starting user operation at the end of 2023. Among others, two small angle neutron scattering (SANS) machines will be operated. Due to the high brilliance of the source, it is important to minimize the downtime of the instruments. For this, a collaboration between three German universities and the ESS was initialized to develop and construct a unified sample environment (SE) system. The main focus was set on the use of a robust carrier system for the different SEs, which allows setting up experiments and first prealignment outside the SANS instruments. This article covers the development and construction of a SE for SANS experiments with foams, which allows measuring foams at different drainage states and the control of the rate of foam formation, temperature, and measurement position. The functionality under ESS conditions was tested and neutron test measurement were carried out.

The FlexiProb project is a joint effort of three soft matter groups at the Universities of Bielefeld, Darmstadt, and Munich with scientific support from the European Spallation Source (ESS), the small-K advanced diffractometer (SKADI) beamline development group of the Jülich Centre for Neutron Science (JCNS), and the Heinz Maier-Leibnitz Zentrum (MLZ). Within this framework, a flexible and quickly interchangeable sample carrier system for small-angle neutron scattering (SANS) at the ESS was developed. In the present contribution, the development of a sample environment for the investigation of soft matter thin films with grazing-incidence small-angle neutron scattering (GISANS) is introduced. Therefore, components were assembled on an optical breadboard for the measurement of thin film samples under controlled ambient conditions, with adjustable temperature and humidity, as well as the optional in situ recording of the film thickness via spectral reflectance. Samples were placed in a 3D-printed spherical humidity metal chamber, which enabled the accurate control of experimental conditions via water-heated channels within its walls. A separately heated gas flow stream supplied an adjustable flow of dry or saturated solvent vapor. First test experiments proved the concept of the setup and respective component functionality.

As part of the development of the new European Spallation Source (ESS) in Lund (Sweden), which will provide the most brilliant neutron beams worldwide, it is necessary to provide different sample environments with which the potential of the new source can be exploited as soon as possible from the start of operation. The overarching goal of the project is to reduce the downtimes of the instruments related to changing the sample environment by developing plug and play sample environments for different soft matter samples using the same general carrier platform and also providing full software integration and control by just using unified connectors. In the present article, as a part of this endeavor, the sample environment for in situ SANS and dynamic light scattering measurements is introduced.

The complete chloroplast genome of Angiopteris yunnanensis has been sequenced and assembled to provide genomic resources to reconstruct the phylogenetic relationship among species of Angiopteris as required to support conservation management of these ancient ferns. The chloroplast genome is 152,962 bp in length with the large single copy (LSC), the small single copy (SSC), and two inverted repeat (IR) regions of length 89,717bp, 20,585bp, and 21,330bp, respectively. We annotated 136 genes in total, including 89 coding genes, 39 tRNAs and 8 rRNAs. Comparative analyses confirmed the conservatism of plastid genome sequences among the species of Angiopteris and the distant related genus Christensenia.

We utilize near-infrared pump—mid-infrared probe spectroscopy to investigate the ultrafast electronic response of pressurized VO _2 . A clear anomaly in the linear mid-infrared response as well as in the fluence dependence of the pump–probe signal is observed around 8 GPa indicating a pressure-induced phase transition. Distinct pump–probe signals and a pumping threshold behavior typical for the insulating VO _2 phase persist also in the high-pressure phase. Thus, in contrast to the temperature-induced rutile metallic state of VO _2 , the pressure-induced monoclinic phase preserves the energy gap. However, our results indicate the appearance and a gradual growth of additional intragap states upon increasing pressure above 8 GPa. These observations can be interpreted in terms of a bandwidth-controlled Mott–Hubbard transition.

BackgroundLejeunea is a largely epiphytic, subcosmopolitan liverwort genus with a complex taxonomic history. Species circumscriptions and their relationships are subject to controversy; biogeographic history and diversification through time are largely unknown.Methodology and resultsWe employed sequences of two chloroplast regions (trnL-trnF, rbcL) and the nuclear ribosomal ITS region of 332 accessions to explore the phylogeny of the Harpalejeunea-Lejeunea-Microlejeunea complex. Lejeunea forms a well-supported clade that splits into two main lineages corresponding to L. subg. Lejeunea and L. subg. Crossotolejeunea. Neotropical accessions dominate early diverging lineages of both main clades of Lejeunea. This pattern suggests an origin in the Neotropics followed by several colonizations from the Neotropics into the Paleotropics and vice versa. Most Afro-Madagascan clades are related to Asian clades. Several temperate Lejeunea radiations were detected. Eighty two of the 91 investigated Lejeunea species could be identified to species level. Of these 82 species, 54 were represented by multiple accessions (25 para- or polyphyletic, 29 monophyletic). Twenty nine of the 36 investigated species of L. subg. Lejeunea were monoicous and 7 dioicous. Within L. subg. Crossotolejeunea, 15 of the 46 investigated species were monoicous and 31 dioicous. Some dioicous as well as some monoicous species have disjunct ranges.Conclusions/significanceWe present the first global phylogeny of Lejeunea and the first example of a Neotropical origin of a Pantropical liverwort genus. Furthermore, we provide evidence for the Neotropics as a cradle of Lejeunea lineages and detect post-colonization radiations in Asia, Australasia, Afro-Madagascar and Europe. Dioicy/monoicy shifts are likely non-randomly distributed. The presented phylogeny points to the need of integrative taxonomical studies to clarify many Lejeunea binomials. Most importantly, it provides a framework for future studies on the diversification of this lineage in space and time, especially in the context of sexual systems in Lejeuneaceae.

Cryptic species are frequently recovered in plant lineages, and considered an important cause for divergent of morphological disparity and species diversity. The identification of cryptic species has important implications for the assessment of conservation needs of species aggregates. The mechanisms and processes of the origin of cryptic species diversity are still poorly understand based on the lack of studies especially in context of environment factors. Here we explored evidence for cryptic species within the epiphyllous liverworts Cololejeunea lanciloba complex based on two loci, the plastid trnL-F region and the nuclear ribosomal ITS region. Several analytic approaches were employed to delimit species based on DNA sequence variation including phylogenetic reconstruction, statistical parsimony networks analysis and two recently introduced species delimitation criteria: Rosenberg's reciprocal monophyly and Rodrigo's randomly distinct. We found evidence for thirteen genetically distinct putative species, each consisting of more than one haplotype, rather than four morphologically-circumscribed species. The results implied that the highly conserved phenotypes are not congruent with the genetic differentiation, contributing to incorrect assessments of the biodiversity of epiphyllous liverworts. We hypothesize that evolution of cryptic species recovered may be caused by selection of traits critical to the survival in epiphyllous habitats combined with limited developmental options designed in the small body.

Cognitive adaptation training (CAT) improves functional outcome in outpatients with schizophrenia living in the United States of America. The efficacy of CAT has never been demonstrated for patients living in a residential facility. We describe how CAT was delivered to two chronically hospitalized patients with schizophrenia living in The Netherlands. CAT was delivered for 8 months, and consisted of weekly home visits by a psychiatric nurse. Both patients improved on measures of functional outcome used in the US studies. These results indicate that CAT may improve outcomes, even in patients that have been hospitalized for several years.

Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK) is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes--while playing an essential role in fern colonization and reproduction--generally lack the morphological complexity for morphology-based identification and have therefore been underappreciated in ecological studies. We evaluated the potential of a combination of rbcL with a noncoding plastid marker, trnL-F, to obtain DNA-identifications for fern species. A regional approach was adopted, by creating a reference database of trusted rbcL and trnL-F sequences for the wild-occurring homosporous ferns of NW-Europe. A combination of parsimony analyses and distance-based analyses was performed to evaluate the discriminatory power of the two-region barcode. DNA was successfully extracted from 86 tiny fern gametophytes and was used as a test case for the performance of DNA-based identification. Primer universality proved high for both markers. Based on the combined rbcL + trnL-F dataset, all genera as well as all species with non-equal chloroplast genomes formed their own well supported monophyletic clade, indicating a high discriminatory power. Interspecific distances were larger than intraspecific distances for all tested taxa. Identification tests on gametophytes showed a comparable result. All test samples could be identified to genus level, species identification was well possible unless they belonged to a pair of Dryopteris species with completely identical chloroplast genomes. Our results suggest a high potential of the combined use of rbcL and trnL-F as a two-locus cpDNA barcode for identification of fern species. A regional approach may be preferred for ecological tests. We here offer such a ready-to-use barcoding approach for ferns, which opens the way for answering a whole range of questions previously unaddressed in fern gametophyte ecology.

The Qinghai-Tibetan Plateau (QTP) and its southern and southeastern mountain ranges, Himalaya-Hengduan Mountains (HHM), are one of the most extensive habitats for alpine plants in the world. How ferns occurring in QTP and HHM changed their distribution ranges in response to Quaternary climatic oscillations remains almost unknown.We employed sequences of two chloroplast DNA regions, rps4-trnS and trnL-trnF, to reconstruct phylogeography of the Sino-Himalayan fern Lepisorus clathratus, occurring mainly in the QTP and HHM. Individuals of this species have either dehiscent or indehiscent sporangia with the latter evolved from the plesiomorphic dehiscent forms. Based on a range-wide sampling, we detected 27 cpDNA haplotypes that were divided into five groups by network analyses. Populations in the Hengduan Mountains possess the highest genetic diversity, while a single haplogroup is detected across the north-central region. A distinct phylogeographical subdivision was detected between the Hengduan Mountains and north-central region by AMOVA analysis. The haplogroup distribution pattern, coalescence and AMOVA analysis suggest that a long term survival area (refugia) of the species was located in the Hengduan Mountains during glaciations, with probable range expansions into north-central regions during interglacial periods. Populations with indehiscent sporangium can carry private haplotypes and are inclined to maintain genetic homogeneity. One group with indehiscent sporangia most likely survived in situ on the QTP during glaciations.This study for the first time sheds light on the response of alpine ferns in the QTP and HHM to the Quaternary climatic oscillations.

BackgroundHigh-throughput tools for pan-genomic study, especially the DNA microarray platform, have sparked a remarkable increase in data production and enabled a shift in the scale at which biological investigation is possible. The use of microarrays to examine evolutionary relationships and processes, however, is predominantly restricted to model or near-model organisms.Methodology/principal findingsThis study explores the utility of Diversity Arrays Technology (DArT) in evolutionary studies of non-model organisms. DArT is a hybridization-based genotyping method that uses microarray technology to identify and type DNA polymorphism. Theoretically applicable to any organism (even one for which no prior genetic data are available), DArT has not yet been explored in exclusively wild sample sets, nor extensively examined in a phylogenetic framework. DArT recovered 1349 markers of largely low copy-number loci in two lineages of seed-free land plants: the diploid fern Asplenium viride and the haploid moss Garovaglia elegans. Direct sequencing of 148 of these DArT markers identified 30 putative loci including four routinely sequenced for evolutionary studies in plants. Phylogenetic analyses of DArT genotypes reveal phylogeographic and substrate specificity patterns in A. viride, a lack of phylogeographic pattern in Australian G. elegans, and additive variation in hybrid or mixed samples.Conclusions/significanceThese results enable methodological recommendations including procedures for detecting and analysing DArT markers tailored specifically to evolutionary investigations and practical factors informing the decision to use DArT, and raise evolutionary hypotheses concerning substrate specificity and biogeographic patterns. Thus DArT is a demonstrably valuable addition to the set of existing molecular approaches used to infer biological phenomena such as adaptive radiations, population dynamics, hybridization, introgression, ecological differentiation and phylogeography.

We investigate the low-energy carrier dynamics in Landau quantized multilayer epitaxial graphene on $(000\bar{1})$ SiC, using 14 meV photons. The THz absorption is dominated by Landau-level transitions within the conduction bands of several graphene layers with different doping. Varying the magnetic field allows us to tune the THz-induced response from induced transmission around B = 0 to induced absorption at intermediate fields (1.5 T–3.3 T) and back to induced transmission at higher fields (3.3 T–7 T). The main features of this complex response are explained by a strong dependence of the absorption on the electron temperature. Furthermore a prolonged relaxation at high fields, which is attributed to reduced scattering via optical phonons, is observed.