Community structure and species diversity dynamics of a subtropical evergreen broad-leaved forest in China:2005 to 2020

Here,we characterize the temporal and spatial dynamics of forest community structure and species diversity in a subtropical evergreen broad-leaved forest in China.We found that community structure in this forest changed over a 15-year period.Specifically,renewal and death of common species was large,with the renewal of individuals mainly concentrated within a few populations,especially those of Aidia canthioides and Cryptocarya concinna.The numbers of individual deaths for common species were concentrated in the small and mid-diameter level.The spatial distribution of community species diversity fluctuated in each monitoring period,showing a more dispersed diversity after the 15-year study period,and the coefficient of variation on quadrats increased.In 2010,the death and renewal of the community and the spatial variation of species diversity were different compared to other survey years.Extreme weather may have affected species regeneration and community stability in our subtropical monsoon evergreen broad-leaved forests.Our findings suggest that strengthening the monitoring and management of the forest community will help better understand the long-and short-term causes of dynamic fluctuations of community structure and species diversity,and reveal the factors that drive changes in community structure.

Strong metal-support interactions between highly dispersed Cu^(+) species and ceria via mix-MOF pyrolysis toward promoted water-gas shift reaction

The modulation of metal-support interfacial interaction is significant but challenging in the design of high-efficiency and high-stability supported catalysts.Here,we report a synthetic strategy to upgrade Cu-CeO_(2)interfacial interaction by the pyrolysis of mixed metal-organic framework(MOF)structure.The obtained highly dispersed Cu/CeO_(2)-MOF catalyst via this strategy was used to catalyze water-gas shift reaction(WGSR),which exhibited high activity of 40.5μmolCOgcat^(-1).s^(-1)at 300℃and high stability of about 120 h.Based on comprehensive studies of electronic structure,pyrolysis strategy has significant effect on enhancing metal-support interaction and then stabilizing interfacial Cu^(+)species under reaction conditions.Abundant Cu^(+)species and generated oxygen vacancies over Cu/CeO_(2)-MOF catalyst played a key role in CO molecule activation and H2O molecule dissociation,respectively.Both collaborated closely and then promoted WGSR catalytic performance in comparison with traditio nal supported catalysts.This study shall offer a robust approach to harvest highly dispersed catalysts with finely-tuned metal-support interactions for stabilizing the most interfacial active metal species in diverse heterogeneous catalytic reactions.

Stomatal dynamics are regulated by leaf hydraulic traits and guard cell anatomy in nine true mangrove species

Stomatal regulation is critical for mangroves to survive in the hyper-saline intertidal zone where water stress is severe and water availability is highly fluctuant.However,very little is known about the stomatal sensitivity to vapour pressure deficit(VPD)in mangroves,and its co-ordination with stomatal morphology and leaf hydraulic traits.We measured the stomatal response to a step increase in VPD in situ,stomatal anatomy,leaf hydraulic vulnerability and pressure-volume traits in nine true mangrove species of five families and collected the data of genome size.We aimed to answer two questions:(1)Does stomatal morphology influence stomatal dynamics in response to a high VPD in mangroves?with a consideration of possible influence of genome size on stomatal morphology;and(2)do leaf hydraulic traits influence stomatal sensitivity to VPD in mangroves?We found that the stomata of mangrove plants were highly sensitive to a step rise in VPD and the stomatal responses were directly affected by stomatal anatomy and hydraulic traits.Smaller,denser stomata was correlated with faster stomatal closure at high VPD across the species of Rhizophoraceae,and stomata size negatively and vein density positively correlated with genome size.Less negative leaf osmotic pressure at the full turgor(πo)was related to higher operating steady-state stomatal conductance(gs);and a higher leaf capacitance(Cleaf)and more embolism resistant leaf xylem were associated with slower stomatal responses to an increase in VPD.In addition,stomatal responsiveness to VPD was indirectly affected by leaf morphological traits,which were affected by site salinity and consequently leaf water status.Our results demonstrate that mangroves display a unique relationship between genome size,stomatal size and vein packing,and that stomatal responsiveness to VPD is regulated by leaf hydraulic traits and stomatal morphology.Our work provides a quantitative framework to better understand of stomatal regulation in mangroves in an environment with high salinity and dynamic water availability.

Predicting changes in the suitable habitats of six halophytic plant species in the arid areas of Northwest China

In the context of changes in global climate and land uses,biodiversity patterns and plant species distributions have been significantly affected.Soil salinization is a growing problem,particularly in the arid areas of Northwest China.Halophytes are ideal for restoring soil salinization because of their adaptability to salt stress.In this study,we collected the current and future bioclimatic data released by the WorldClim database,along with soil data from the Harmonized World Soil Database(v1.2)and A Big Earth Data Platform for Three Poles.Using the maximum entropy(MaxEnt)model,the potential suitable habitats of six halophytic plant species(Halostachys caspica(Bieb.)C.A.Mey.,Halogeton glomeratus(Bieb.)C.A.Mey.,Kalidium foliatum(Pall.)Moq.,Halocnemum strobilaceum(Pall.)Bieb.,Salicornia europaea L.,and Suaeda salsa(L.)Pall.)were assessed under the current climate conditions(average for 1970-2000)and future(2050s,2070s,and 2090s)climate scenarios(SSP245 and SSP585,where SSP is the Shared Socio-economic Pathway).The results revealed that all six halophytic plant species exhibited the area under the receiver operating characteristic curve values higher than 0.80 based on the MaxEnt model,indicating the excellent performance of the MaxEnt model.The suitability of the six halophytic plant species significantly varied across regions in the arid areas of Northwest China.Under different future climate change scenarios,the suitable habitat areas for the six halophytic plant species are expected to increase or decrease to varying degrees.As global warming progresses,the suitable habitat areas of K.foliatum,S.salsa,and H.strobilaceum exhibited an increasing trend.In contrast,the suitable habitat areas of H.glomeratus,S.europaea,and H.caspica showed an opposite trend.Furthermore,considering the ongoing global warming trend,the centroids of the suitable habitat areas for various halophytic plant species would migrate to different degrees,and four halophytic plant species,namely,S.salsa,H.strobilaceum,H.glomeratus,and H.capsica,would migrate to higher latitudes.Temperature,precipitation,and soil factors affected the possible distribution ranges of these six halophytic plant species.Among them,precipitation seasonality(coefficient of variation),precipitation of the warmest quarter,mean temperature of the warmest quarter,and exchangeable Na+significantly affected the distribution of halophytic plant species.Our findings are critical to comprehending and predicting the impact of climate change on ecosystems.The findings of this study hold significant theoretical and practical implications for the management of soil salinization and for the utilization,protection,and management of halophytes in the arid areas of Northwest China.

Testing complete plastomes and nuclear ribosomal DNA sequences for species identification in a taxonomically difficult bamboo genus Fargesia

Fargesia,the largest genus within the temperate bamboo tribe Arundinarieae,has more than 90 species mainly distributed in the mountains of Southwest China.The Fargesia bamboos are important components of the subalpine forest ecosystems that provide food and habitat for many endangered animals,including the giant panda.However,species-level identification of Fargesia is difficult.Moreover,the rapid radiation and slow molecular evolutionary rate of Fargesia pose a significant challenge to using DNA barcoding with standard plant barcodes(rbcL,matK,and ITS) in bamboos.With progress in the sequencing technologies,complete plastid genomes(plastomes) and nuclear ribosomal DNA(nrDNA)sequences have been proposed as organelle barcodes for species identification;however,these have not been tested in bamboos.We collected 196 individuals representing 62 species of Fargesia to comprehensively evaluate the discriminatory power of plastomes and nrDNA sequences compared to standard barcodes.Our analysis indicates that complete plastomes have substantially higher discriminatory power(28.6%) than standard barcodes(5.7%),whereas nrDNA sequences show a moderate improvement(65.4%) compared to ITS(47.2%).We also found that nuclear markers performed better than plastid markers,and ITS alone had higher discriminatory power than complete plastomes.The study also demonstrated that plastomes and nrDNA sequences can contribute to intrageneric phylogenetic resolution in Fargesia.However,neither of these sequences were able to discriminate all the sampled species,and therefore,more nuclear markers need to be identified.

The identity of Dinochloa species and enumeration of Melocalamus(Poaceae:Bambusoideae) in China

Three woody bamboo species collected in Hainan,China in 1940 have been described as Dinochloa based on vegetative specimens.However,the identity of these species has long been in doubt,largely because the vegetative phase in species of Dinochloa is morphologically similar to that in species of Melocalamus,a climbing or scrambling bamboo genus of the paleotropical woody bamboos(Poaceae:Bambusoideae)that consists of about 15 species and one variety.To determine the phylogenetic affinity of the three Dinochloa species from Hainan,we sampled almost all recognized Chinese species of Melocalamus and representative species of Dinochloa as well as other closely related genera,performed molecular phylogenetic analysis,and compared their morphology based on herbarium and fieldwork investigation.Our ddRAD data indicate that the three species from Hainan are closely related to Melocalamus,not Dinochloa.Morphological analysis showed that these three species have a climbing habit but do not grow spirally,their culm leaves have smooth bases,and there is a ring of powder and/or tomenta above and below the nodes.Taken together our findings indicate that the three species from Hainan originally published in Dinochloa should be transferred to Melocalamus,i.e.,Melocalamus orenudus(McClure) D.Z.Li& J.X.Liu,Melocalamus puberulus(McClure) D.Z.Li & J.X.Liu,and Melocalamus utilis(McClure) D.Z.Li &J.X.Liu,respectively.This study concludes with an enumeration of Chinese species of Melocalamus,with a key to nine recognized species and one variety,and a lectotypification for M. compatiflorus.

Comparative Performance of Microscopy and Nested PCR for the Detection of Cryptosporidium Species in Patients Living with HIV/AIDS in Abidjan (Côte d’Ivoire)

Cryptosporidium spp. infection is one of the causes of diarrhea in people living with HIV/AIDS. The objective of this study is to compare the sensitivity of microscopy and molecular biology to determine the prevalence of Cryptosporidium spp. in Patients Living With HIV (PLWH). This is a descriptive cross-sectional study conducted in three care centers for people living with HIV/AIDS in Abidjan. It took place from November 2018 to March 2020. Sociodemographic data were obtained via a questionnaire. Stool and blood samples were collected and analyzed for microscopy and Nested PCR detection of Cryptosporidium spp. Blood samples were analyzed for CD4+ count. A total of 363 stool samples were collected from the three sites. Individuals aged 40 - 50 years (36.52%) were most likely to participate in the study. HIV Type 1 accounted for 86.22% of the study population. The samples collected consisted of 47.65% diarrheal stool. Microscopic examination of the stool yielded a prevalence of 3.86% for Cryptosporidium spp. while the prevalence was 3.96% with molecular identification. No statistically significant difference was observed between these two prevalences (χ2 = 0.26;p = 0.609). CD4+ count was the factor associated with Cryptosporidium spp. infection for both microscopy (OR = 0.887, p = 0.001) and PCR (OR = 0.896, p = 0.001). This study demonstrated that Nested PCR improves the detection of Cryptosporidium spp. in patient diagnosis.

Distributional responses to climate change for alpine species of Cyananthus and Primula endemic to the Himalaya-Hengduan Mountains

Global warming increases the vulnerability of plants, especially alpine herbaceous species, to local extinction. In this study, we collected species distribution information from herbarium specimens for ten selected Cyananthus and Primula alpine species endemic to the Himalaya-Hengduan Mountains(HHM).Combined with climate data from WorldClim, we used Maximum Entropy Modeling(MaxEnt) to project distributional changes from the current time period to 2070. Our predictions indicate that, under a wide range of climate change scenarios, the distributions of all species will shift upward in elevation and northward in latitude; furthermore, under these scenarios, species will expand the size of their range. For the majority of the species in this study, habitats are available to mitigate upward and northward shifts that are projected to be induced by changing climate. If current climate projections, however, increase in magnitude or continue to increase past our projection dates, suitable habitat for future occupation by alpine species will be limited as we predict range contraction or less range expansion for some of the species under more intensified climate scenarios. Our study not only underscores the value of herbarium source information for future climate model projections but also suggests that future studies on the effects of climate change on alpine species should include additional biotic and abiotic factors to provide greater resolution of the local dynamics associated with species persistence under a warming climate.

Plant species with extremely small populations(PSESP) in China:A seed and spore biology perspective

Approximately one fifth of the world's plants are at risk of extinction.Of these,a significant number exist as populations of few individuals,with limited distribution ranges and under enormous pressure due to habitat destruction.In China,these most-at-risk species are described as 'plant species with extremely small populations'(PSESP).Implementing conservation action for such listed species is urgent.Storing seeds is one of the main means of ex situ conservation for flowering plants.Spore storage could provide a simple and economical method for fern ex situ conservation.Seed and spore germination in nature is a critical step in species regeneration and thus in situ conservation.But what is known about the seed and spore biology(storage and germination) of at-risk species? We have used China's PSESP(the first group listing) as a case study to understand the gaps in knowledge on propagule biology of threatened plant species.We found that whilst germination information is available for 28 species(23%of PSESP),storage characteristics are only known for 8%of PSESP(10 species).Moreover,we estimate that 60%of the listed species may require cryopreservation for long-term storage.We conclude that comparative biology studies are urgently needed on the world's most threatened taxa so that conservation action can progress beyond species listing.

Trait variation and functional diversity maintenance of understory herbaceous species coexisting along an elevational gradient in Yulong Mountain,Southwest China

Characterizing trait variation across different ecological scales in plant communities has been viewed as a way to gain insights into the mechanisms driving species coexistence.However,little is known about how changes in intraspecific and interspecific traits across sites influence species richness and community assembly,especially in understory herbaceous communities.Here we partitioned the variance of four functional traits(maximum height,leaf thickness,leaf area and specific leaf area)across four nested biological scales:individual,species,plot,and elevation to quantify the scale-dependent distributions of understory herbaceous trait variance.We also integrated the comparison of the trait variance ratios to null models to investigate the effects of different ecological processes on community assembly and functional diversity along a 1200-m elevational gradient in Yulong Mountain.We found interspecific trait variation was the main trait variation component for leaf traits,although intraspecific trait variation ranged from 10% to 28% of total variation.In particular,maximum height exhibited high plasticity,and intraspecific variation accounted for 44% of the total variation.Despite the fact that species composition varied across elevation and species richness decreased dramatically along the elevational gradient,there was little variance at our largest(elevation)scale in leaf traits and functional diversity remained constant along the elevational gradient,indicating that traits responded to smaller scale influences.External filtering was only observed at high elevations.However,strong internal filtering was detected along the entire elevational gradient in understory herbaceous communities,possibly due to competition.Our results provide evidence that species coexistence in understory herbaceous communities might be structured by differential niche-assembled processes.This approach ee integrating different biological scales of trait variation ee may provide a better understanding of the mechanisms involved in the structure of communities.

Comparative population genetic analyses suggest hybrid origin of Rhododendron pubicostatum,an endangered plant species with extremely small populations endemic to Yunnan,China

Gene flow between sympatric congeneric plants is thought to be very common and may pose serious threats to endangered species.In the present study,we evaluate the genetic diversity and divergence of three sympatric Rhododendron species in Jiaozi Mountain using newly developed microsatellites through the Illumina MiSeq sequencing approach.Genetic diversity of all three Rhododendron species studied was moderate in comparison to genetic parameters previously reported from species of this genus.Interestingly,genetic structure analysis of the three species identified a possible hybrid origin of the threatened Rh.pubicostatum.This sympatry should be considered a unimodal hybrid zone,since Rh.pubicostatum is predominant here.Unimodal hybrid zones are uncommon in Rhododendron,despite the fact that hybridization frequently occurs in the genus.Issues pertaining to the conservation of Rh.pubicostatum resulting from admixture of genetic material from its parental species are discussed.

Using MiddRAD-seq data to develop polymorphic microsatellite markers for an endangered yew species

Microsatellites are highly polymorphic markers which have been used in a wide range of genetic studies.In recent years, various sources of next-generation sequencing data have been used to develop new microsatellite loci, but compared with the more common shotgun genomic sequencing or transcriptome data, the potential utility of RAD-seq data for microsatellite ascertainment is comparatively under-used.In this study, we employed MiddRAD-seq data to develop polymorphic microsatellite loci for the endangered yew species Taxus florinii. Of 8,823,053 clean reads generated for ten individuals of a population, 94,851(~1%) contained microsatellite motifs. These corresponded to 2993 unique loci, of which 526(~18%) exhibited polymorphism. Of which, 237 were suitable for designing microsatellite primer pairs, and 128 loci were randomly selected for PCR validation and microsatellite screening. Out of the 128 primer pairs, 16 loci gave clear, reproducible patterns, and were then screened and characterized in 24 individuals from two populations. The total number of alleles per locus ranged from two to ten(mean=4.875), and within-population expected heterozygosity from zero to 0.789(mean = 0.530),indicating that these microsatellite loci will be useful for population genetics and speciation studies of T. florinii. This study represents one of few examples to mine polymorphic microsatellite loci from ddRAD data.

Two new species of Yushania(Poaceae:Bambusoideae)from South China,with a taxonomic revision of related species

Two new species of Yushania(Poaceae,Bambusoideae,Arundinarieae)are described and illustrated from Hunan,China.Yushania longshanensis D.Z.Li&X.Y.Ye is distinguished from related species(Y.confusa,Y.angustifolia and Y.pachyclada)by having a thinner culm(0.2e0.3 cm in diameter),glabrous sheath scar,no oral setae,a large glabrous leaf blade(10e200.9e1.3 cm)and 3e4 pairs of secondary veins.Yushania stoloniforma D.Z.Li&X.Y.Ye has a distinctive scrambling habit,which differs from its putative close allies.Both of these two new species have a solitary branch at the basal nodes and can be assigned to Yushania sect.Yushania based on morphological features.Additionally,we treated Yushania gigantea T.P.Yi&L.Yang as a new synonym of Y.elevata T.P.Yi and renamed Y.microphylla T.P.Yi&L.Yang as Y.weiningensis D.Z.Li&X.Y.Ye.

Genetic diversity and population structure of Hibiscus aridicola, an endangered ornamental species in dry-hot valleys of Jinsha River

Hibiscus aridicola is an endangered ornamental shrub of the family Malvaceae that is endemic to the dryhot valleys of Jinsha River in southwestern China.This species is a typical plant species with extremely small populations(PSESP).To support and monitor future conservation,develop management measures,and genotype this species,we performed extensive field studies together with genetic analyses.Specifically,we screened eleven microsatellite loci of 69 individuals of H.aridicola from four accessions.The population genetics analyses indicated that H.aridicola possesses high genetic diversity at both the population(0.6962-0.7293)and species level(0.7837)compared to other endemic/endangered species in China.The low differentiation of populations(Fst=0.0971)and the high gene flow between populations of H.aridicola(Nm=2.3236)could be due to its distribution along rivers in the hot-valleys of the Jinsha River and the wind-mediated dispersal of its seeds.Furthermore,the genetic diversity of H.aridicola is slightly positively correlated with geographic distance.Two populations are undergoing a genetic bottleneck,and require more specific attention from conservationists.Additionally,our analyses of the population genetics of H.aridicola demonstrate that the declines in populations are not the result of the internal genetics of these populations but due to external human activities over the past decades.

Elevational patterns of bird species richness on the eastern slope of Mt.Gongga,Sichuan Province,China

Background:In biological systems,biological diversity often displays a rapid turn-over across elevations.This defining feature has made mountains classic systems for studying the spatial variation in diversity.Because patterns of elevational diversity can vary among lineages and mountain systems it remains difficult to extrapolate findings from one montane region to another,or among lineages.In this study,we assessed patterns and drivers of avian diversity along an elevational gradient on the eastern slope of Mt.Gongga,the highest peak in the Hengduan Mountain Range in central China,and a mountain where comprehensive studies of avian diversity are still lacking.Methods:We surveyed bird species in eight 400-m elevational bands from 1200 to 4400 m a.s.l.between 2012 and 2017.To test the relationship between bird species richness and environmental factors,we examined the relative importance of seven ecological variables on breeding season distribution patterns:land area(LA),mean daily temperature(MDT),seasonal temperature range(STR),the mid-domain effect(MDE),seasonal precipitation(SP),invertebrate biomass(IB) and enhanced vegetation index(EVI).Climate data were obtained from five local meteorological stations and three temperature/relative humidity smart sensors in 2016.Results:A total of 219 bird species were recorded in the field,of which 204 were recorded during the breeding season(April–August).Species richness curves(calculated separately for total species,large-ranged species,and smallranged species) were all hump-shaped.Large-ranged species contributed more to the total species richness pattern than small-ranged species.EVI and IB were positively correlated with total species richness and small-ranged species richness.LA and MDT were positively correlated with small-ranged species richness,while STR and SP were negatively correlated with small-ranged species richness.MDE was positively correlated with large-ranged species richness.When we considered the combination of candidate factors using multiple regression models and model-averaging,total species richness and large-ranged species richness were correlated with STR(negative) and MDE(positive),while small-ranged species richness was correlated with STR(negative) and IB(positive).Conclusions:Although no single key factor or suite of factors could explain patterns of diversity,we found that MDE,IB and STR play important but varying roles in shaping the elevational richness patterns of different bird species categories.Model-averaging indicates that small-ranged species appear to be mostly influenced by IB,as opposed to large-ranged species,which exhibit patterns more consistent with the MDE model.Our data also indicate that the species richness varied between seasons,offering a promising direction for future work.

Taxonomy notes on Vandeae(Orchidaceae)from China:Five new species and two new records

Five new species(Gastrochilus yei,Gastrochilus minimus,Luisia simaoensis,Taeniophyllum xizangense,Tuberolabium subulatum)and two newly recorded species(Cleisostoma tricornutum,Luisia inconspicua)of Vandeae(Orchidaceae)from China are described and illustrated.Gastrochilus yei is similar to G.affinis and G.nepalensis,but differs from them by having an epichile not lobed,the apex of the hypochile not bilobed,and a tine on the apex of the leaf.Gastrochilus minimus is similar to G.acinacifolius,but can be distinguished from the latter by having a flabellate epichile that is densely hirsute on the adaxial surface and an inconspicuous central cushion;in addition,the hypochile of G.minimus has a keel that extends to the apex of the epichile.Taeniophyllum xizangense is similar to T.stella and T.radiatum,but it is distinguished from them by having much bigger flowers,inflorescences densely covered with short-bristly hairs,papillae on the external surface of sepals,and bigger triangular-ovate viscidium.Luisia simaoensis is similar to L magniflora and L ramosii,but can be easily distinguished from them by having lateral sepals longer than dorsal sepals and petals,lip with irregular and waved margins,and lip with bilobed apex.Luisia inconspicua is moved from Gastrochilus to Luisia based on phylogenetic analyses of plastid matK sequence data.Tuberolabium subulatum is similar to T.camosum,but it can be easily distinguished from the latter by having an inflorescence much shorter than the leaves,yellow sepals and petals,and many small papillae outside the lip lobes.

Rhododendron kuomeianum(Ericaceae),a new species from northeastern Yunnan(China),based on morphological and genomic data

Rhododendron kuomeianum Y.H.Chang,J.Nielsen&Y.P.Ma,a new species of Rhododendron(Ericaceae)within subsect.Maddenia in sect.Rhododendron from Yiliang County,NE Yunnan,China,is described and illustrated.The new species is similar to R.valentinianum,but it can be easily distinguished by its sparse scales on the abaxial surface of the leaf blade,fewer flowers per inflorescence and white corolla with pale red margins.There are also differences in the widths of calyx lobes,leaf blade shape and indumentum characteristics of the petiole between the new species and Rhododendron linearilobum.We confirmed that R.kuomeianum is a new species closely related to R.valentinianum and R.changii with phylogenomic studies of 10 species within this subsection based on restriction site-associated DNA sequencing(RADseq)data.These phylogenomic analyses also clarified additional taxonomic problems in this subsection previously raised by morphological analysis.Our findings make a strong case for using next-generation sequencing to explore phylogenetic relationships and identify new species,especially in plants groups with complicated taxonomic problems.

Integrative taxonomy of the Russet Bush Warbler Locustella mandelli complex reveals a new species from central China

Background: The Russet Bush Warbler Locustella(previously Bradypterus) mandelli complex occurs in mountains in the eastern Himalayas, southern China, Vietnam, the Philippines, and Indonesia. The taxonomy has been debated,with one(L. seebohmi) to four(L. seebohmi, L. mandelli, L. montis and L. timorensis) species having been recognised.Methods: We used an integrative approach, incorporating analyses of morphology, vocalizations and a molecular marker, to re-evaluate species limits in the L. mandelli complex.Results: We found that central Chinese L. mandelli differed from those from India through northern Southeast Asia to southeast China in plumage, morphometrics and song. All were easily classified by song, and(wing + culmen)/tail ratio overlapped only marginally. Both groups were reciprocally monophyletic in a mitochondrial cytochrome b(cytb) gene tree, with a mean divergence of 1.0 ± 0.2%. They were sympatric and mostly altitudinally segregated in the breeding season in southern Sichuan province. We found that the Mt Victoria(western Myanmar) population differed vocally from other L. mandelli, but no specimens are available. Taiwan Bush Warbler L. alishanensis was sister to the L. mandelli complex, with the most divergent song. Plumage, vocal and cytb evidence supported the distinctness of the south Vietnamese L. mandelli idonea. The Timor Bush Warbler L. timorensis, Javan Bush Warbler L.montis and Benguet Bush Warbler L. seebohmi differed distinctly in plumage, but among-population song variation in L. montis exceeded the differences between some populations of these taxa, and mean pairwise cytb divergences were only 0.5–0.9%. We also found that some L. montis populations differed morphologically.Conclusions: We conclude that the central Chinese population of Russet Bush Warbler represents a new species,which we describe herein, breeding at mid elevations in Sichuan, Shaanxi, Hubei, Hunan and Guizhou provinces.The taxonomic status of the other allopatric populations is less clear. However, as they differ to a degree comparable with that of the sympatric L. mandelli and the new species, we elevate L. idonea to species status, and retain L. seebohmi and L. montis as separate species, the latter with timorensis as a subspecies. Further research should focus on different populations of L. montis and the Mt Victoria population of L. mandelli.

Multiple lines of evidence supports the two varieties of Halenia elliptica(Gentianaceae)as two species

Delimiting species requires multiple sources of evidence.Here,we delimited two varieties of Halenia elliptica(Gentianaceae)using several lines of evidence,including morphological traits and mating system in a sympatric population,phylogenetic relationships based on nrITS and cpDNA(rpl16)data,and complete chloroplast genome sequences.Comparative analysis of 21 morphological traits clearly separates the two varieties of H.elliptica.Examination of the flowering process and pollination treatments indicate that H.elliptica var.grandiflora produces seeds via outcrossing,whereas H.elliptica var.elliptica produces seeds via mixed mating.Furthermore,hand-pollinated hybridization of the two varieties produced no seeds.Observations of pollinators showed that when bees began a pollination bout on H.elliptica var.grandiflora they preferred to continue pollinating this variety;however,when they began a pollination bout on H.elliptica var.elliptica,they showed no preference for either variety.Phylogenetic analysis confirmed the monophyly of H.elliptica,which was further divided into two monophyletic clades corresponding to the two varieties.A large number of variants from the chloroplast genomes reflected remarkable genetic dissimilarities between the two varieties of H.elliptica.We recommend that the two varieties of H.elliptica should be revised as two species(H.elliptica and H.grandiflora).Our findings indicate that H.elliptica varieties may have split into two separate species due to a shift in mating system,changes in flowering phenology and/or post-pollination reproductive isolation.

Mitogenomic phylogeny of the Asian colobine genus Trachypithecus with special focus on Trachypithecus phayrei(Blyth, 1847) and description of a new species

Trachypithecus,which currently contains 20 species divided into four groups,is the most speciose and geographically dispersed genus among Asian colobines.Despite several morphological and molecular studies,however,its evolutionary history and phylogeography remain poorly understood.Phayre’s langur(Trachypithecus phayrei) is one of the most widespread members of the genus,but details on its actual distribution and intraspecific taxonomy are limited and controversial.Thus,to elucidate the evolutionary history of Trachypithecus and to clarify the intraspecific taxonomy and distribution of T.phayrei,we sequenced 41 mitochondrial genomes from georeferenced fecal samples and museum specimens,including two holotypes.Phylogenetic analyses revealed a robustly supported phylogeny of Trachypithecus,suggesting that the T.pileatus group branched first,followed by the T.francoisi group,and the T.cristatus and T.obscurus groups most recently.The four species groups diverged from each other 4.5-3.1 million years ago(Ma),while speciation events within these groups occurred much more recently(1.6-0.3 Ma).Within T.phayrei,we found three clades that diverged 1.0-0.9 Ma,indicating the existence of three rather than two taxa.Following the phylogenetic species concept and based on genetic,morphological,and ecological differences,we elevate the T.phayrei subspecies to species level,describe a new species from central Myanmar,and refine the distribution of the three taxa.Overall,our study highlights the importance of museum specimens and provides new insights not only into the evolutionary history of T.phayrei but the entire Trachypithecus genus as well.