Across two phylogeographic breaks: Quaternary evolutionary history of a mountain aspen (Populus rotundifolia) in the Hengduan Mountains

Biogeographical barriers to gene flow are central to plant phylogeography.In East Asia,plant distribution is greatly influenced by two phylogeographic breaks,the Mekong-Salween Divide and Tanaka-Kaiyong Line,however,few studies have investigated how these barriers affect the genetic diversity of species that are distributed across both.Here we used 14 microsatellite loci and four chloroplast DNA fragments to examine genetic diversity and distribution patterns of 49 populations of Populus rotundifolia,a species that spans both the Mekong-Salween Divide and the Tanaka-Kaiyong Line in southwestern China.Demographic and migration hypotheses were tested using coalescent-based approaches.Limited historical gene flow was observed between the western and eastern groups of P.rotundifolia,but substantial flow occurred across both the Mekong-Salween Divide and Tanaka-Kaiyong Line,manifesting in clear admixture and high genetic diversity in the central group.Wind-borne pollen and seeds may have facilitated the dispersal of P.rotundifolia following prevalent northwest winds in the spring.We also found that the Hengduan Mountains,where multiple genetic barriers were detected,acted on the whole as a barrier between the western and eastern groups of P.rotundifolia.Ecological niche modeling suggested that P.rotundifolia has undergone range expansion since the last glacial maximum,and demographic reconstruction indicated an earlier population expansion around 600 Ka.The phylogeographic pattern of P.rotundifolia reflects the interplay of biological traits,wind patterns,barriers,niche differentiation,and Quaternary climate history.This study emphasizes the need for multiple lines of evidence in understanding the Quaternary evolution of plants in topographically complex areas.

Cryptic divergences and repeated hybridizations within the endangered “living fossil” dove tree(Davidia involucrata) revealed by whole genome resequencing

The identification and understanding of cryptic intraspecific evolutionary units(lineages) are crucial for planning effective conservation strategies aimed at preserving genetic diversity in endangered species.However, the factors driving the evolution and maintenance of these intraspecific lineages in most endangered species remain poorly understood. In this study, we conducted resequencing of 77 individuals from 22 natural populations of Davidia involucrata, a “living fossil” dove tree endemic to central and southwest China. Our analysis revealed the presence of three distinct local lineages within this endangered species, which emerged approximately 3.09 and 0.32 million years ago. These divergence events align well with the geographic and climatic oscillations that occurred across the distributional range.Additionally, we observed frequent hybridization events between the three lineages, resulting in the formation of hybrid populations in their adjacent as well as disjunct regions. These hybridizations likely arose from climate-driven population expansion and/or long-distance gene flow. Furthermore, we identified numerous environment-correlated gene variants across the total and many other genes that exhibited signals of positive evolution during the maintenance of two major local lineages. Our findings shed light on the highly dynamic evolution underlying the remarkably similar phenotype of this endangered species. Importantly, these results not only provide guidance for the development of conservation plans but also enhance our understanding of evolutionary past for this and other endangered species with similar histories.

Integrating high-volume molecular and morphological data into the evolutionary studies of Allium

The genus Allium(Amaryllidaceae),which includes economically important plants such as onions,garlic,and leeks,is one of the most species-rich and diverse genera of monocotyledon plants in the Northern Hemisphere(Govaerts et al.,2021),with approximately 1000 species.The evolution of Allium is characterized by ecological diversification,with most species preferring open.

Wind-dispersed seeds blur phylogeographic breaks:The complex evolutionary history of Populus lasiocarpa around the Sichuan Basin

The strength of phylogeographic breaks can vary among species in the same area despite being subject to the same geological and climate history due to differences in biological traits.Several important phylogeographic breaks exist around the Sichuan Basin in Southwest China but few studies have focused on wind-dispersed plants.Here,we investigated the phylogeographic patterns and the evolutionary history of Populus lasiocarpa,a wind-pollinated and wind-dispersed tree species with a circum-Sichuan Basin distribution in southwest China.We sequenced and analyzed three plastid DNA fragments(ptDNA) and eight nuclear microsatellites(nSSRs) of 265 individuals of P.lasiocarpa from 21 populations spanning the entire distribution range.Distribution patterns based on nSSR data revealed that there are three genetic groups in P.lasiocarpa.This is consistent with the three phylogeographic breaks(Sichuan Basin,the Kaiyong Line and the 105°E line),where the Sichuan basin acts as the main barrier to gene flow between western and eastern groups.However,the distribution pattern based on ptDNA haplotypes poorly matched the phylogeographic breaks,and wind-dispersed seeds may be one of the main contributing factors.Species distribution modelling suggested a larger potential distribution in the last glacial maximum with a severe bottleneck during the last interglacial.A DIYABC model also suggested a population contraction and expansion for both western and eastern lineages.These results indicate that biological traits are likely to affect the evolutionary history of plants,and that nuclear molecular markers,which experience higher levels of gene flow,might be better indicators of phylogeographic breaks.

Habitats shape root-associated fungal and bacterial communities of Minjiang fir saplings

Root-associated microbes play an essentialrole in mediating plant growth,health,and habitat adaptability.However,it is unknown which microbial taxa help develop host fitness and how habitats shape root-associated microbial assembly patterns.As an endemic species of subalpine forests in western Sichuan,China,Minjiang fir(Abies fargesii var.faxoniana)is dominant on cold-shaded northwestern slopes while absent on warm sunlit southwestern slopes.In this study,fungal and bacterial communities were investigated in three spatial compartments(endosphere,rhizosphere,and bulk soil)associated with Minjiang fir saplings on a cold-shaded northwestern slope and a warm sunlit southwestern slope.Habitats differentiated the microbial communities regardless of the spatial compartment and microbial taxa.Slope aspect variations caused shifts in root-associated(rhizosphere and endosphere)microbial compositions.Compared with the southwestern slope,the cold-shaded northwestern slope harbored a higher abundance of the growth-promoting bacteria Burkholderia and ectomycorrhizal fungi Cortinarius and Piloderma.The slope aspect had stronger effects on fungal diversity than bacterial diversity,with higher fungal endemism and lower bacterial endemism.Slope aspect variations were the dominant drivers of root-associated microbial communities,with lower contribution by soil properties and higher contribution by plant traits on the northwestern slope.Findings from this study could improve the understanding of plant habitat adaptability from the perspective of microbial community assembly.It is suggested that forest management should consider root-associated microbiomes for enhancing species fitness and habitat adaptability.

Genome-wide characterization of the tomato GASA family identifies SlGASA1 as a repressor of fruit ripening

Gibberellins(GAs)play crucial roles in a wide range of developmental processes and stress responses in plants.However,the roles of GA-responsive genes in tomato(Solanum lycopersicum)fruit development remain largely unknown.Here,we identify 17 GASA(Gibberellic Acid-Stimulated Arabidopsis)family genes in tomato.These genes encode proteins with a cleavable signal peptide at their N terminus and a conserved GASA domain at their C terminus.The expression levels of all tomato GASA family genes were responsive to exogenous GA treatment,but adding ethylene eliminated this effect.Comprehensive expression profiling of SlGASA family genes showed that SlGASA1 follows a ripening-associated expression pattern,with low expression levels during fruit ripening,suggesting it plays a negative role in regulating ripening.Overexpressing SlGASA1 using a ripening-specific promoter delayed the onset of fruit ripening,whereas SlGASA1-knockdown fruits displayed accelerated ripening.Consistent with their delayed ripening,SlGASA1-overexpressing fruits showed significantly reduced ethylene production and carotenoid contents compared to the wild type.Moreover,ripening-related genes were downregulated in SlGASA1-overexpressing fruits but upregulated in SlGASA1-knockdown fruits compared to the wild type.Yeast two-hybrid,co-immunoprecipitation,transactivation,and DNA pull-down assays indicated that SlGASA1 interacts with the key ripening regulator FRUITFULL1 and represses its activation of the ethylene biosynthesis genes ACS2 and ACO1.Our findings shed new light on the role and mode of action of a GA-responsive gene in tomato fruit ripening.

Kiwifruit(Actinidia chinensis)R1R2R3-MYB transcription factor AcMYB3R enhances drought and salinity tolerance in Arabidopsis thaliana

Kiwifruit is an important fruit crop that is highly sensitive to environmental stresses,such as drought,heat,cold,water logging and phytopathogens.Therefore it is indispensable to identify stress-responsive candidate genes in kiwifruit cultivars for the stress resistance improvement.Here we report the isolation and characterization of a novel kiwifruit R1R2R3-MYB homolog(AcMYB3R)whose expression was induced by drought,salinity and cold stress.In vitro assays showed that AcMYB3R is a nuclear protein with transcriptional activation activity by binding to the cis-element of the kiwifruit orthologue of G2/M phase-specific gene KNOLLE.The Arabidopsis transgenic plants overexpressing AcMYB3R showed drastically enhanced tolerance to drought and salt stress.The expressions of stress-responsive genes such as RD29A,RD29B,COR15A and RD22 were prominently up-regulated by ectopic expression of Ac MYB3R.Our study provides a valuable piece of information for functional genomics studies of kiwifruit and molecular breeding in improving stress tolerance for crop production.

A high-quality Actinidia chinensis(kiwifruit)genome

Actinidia chinensis(kiwifruit)is a perennial horticultural crop species of the Actinidiaceae family with high nutritional and economic value.Two versions of the A.chinensis genomes have been previously assembled,based mainly on relatively short reads.Here,we report an improved chromosome-level reference genome of A.chinensis(v3.0),based mainly on PacBio long reads and Hi-C data.The high-quality assembled genome is 653 Mb long,with 0.76%heterozygosity.At least 43%of the genome consists of repetitive sequences,and the most abundant long terminal repeats were further identified and account for 23.38%of our novel genome.It has clear improvements in contiguity,accuracy,and gene annotation over the two previous versions and contains 40,464 annotated protein-coding genes,of which 94.41%are functionally annotated.Moreover,further analyses of genetic collinearity revealed that the kiwifruit genome has undergone two whole-genome duplications:one affecting all Ericales families near the K-T extinction event and a recent genus-specific duplication.The reference genome presented here will be highly useful for further molecular elucidation of diverse traits and for the breeding of this horticultural crop,as well as evolutionary studies with related taxa.

A New Species of the Genus Trimeresurus from Southwest China(Squamata:Viperidae)

Species from the Trimeresurus popeiorum complex(Subgenus: Popeia) is a very complex group. T. popeiorum is the only Popeia species known from China. During the past two years, five adult Popeia specimens(4 males, 1 female) were collected from Yingjiang County, Southern Yunnan, China. Molecular, morphological and ecological data show distinct differences from known species, herein we describe these specimens as a new species Trimeresurus yingjiangensis sp. nov Chen, Ding, Shi and Zhang, 2018. Morphologically, the new species distinct from other Popeia species by a combination of following characters:(1) dorsal body olive drab,without cross bands on the scales;(2) a conspicuous bicolor ventrolateral stripe present on each side of males, first row of dorsal scales firebrick with a white ellipse dot on posterior upper part in male, these strips absent in females;(3) eyes firebrick in both gender;(4) suboculars separated from 3rd upper labial by one scale on each side;(5) ventrals 164–168(n = 5);(6) MSR 21.

Plastome and phylogenetic relationship of the woody buckwheat Fagopyrum tibeticum in the Qinghai-Tibet Plateau

The phylogenetic position of the monotypic woody Parapteropyrum(Polygonaceae)remains controversial.Parapteropyrum has been thought to be closely related to the woody genera of the tribe Atraphaxideae,although some evidence indicates that it nests within the herbal buckwheat genus Fagopyrum of tribe Polygoneae.In this study,we used plastome data to determine the phylogenetic position of Parapteropyrum(Fagopyrum)tibeticum.Different reference species were used to assemble plastomes of three species currently placed in the tribe Ataphaxideae:Parapteropyrum(Fagopyrum)tibeticum,Atraphaxis bracteata and Calligonum ebinuricum.Once assembled,plastomes were characterized and compared to plastomes of 12 species across the family Polygonaceae.Phylogenetic analyses of Polygonaceae were performed using whole plastome,all plastome genes,and single-copy genes.Plastomes assembled using different reference plastomes did not differ;however,annotations showed small variation.Plastomes of Parapteropyrum(Fagopyrum)tibeticum,A.bracteata and C.ebinuricum have the typical quadripartite structure with lengths between 159,265 bp and 164,270 bp,and a total number of plastome genes of about 130.Plastome microsatellites(SSR)ranged in number from 48 to 77.Maximum Likelihood and Bayesian analyses of three plastome data sets consistently nested Parapteropyrum within the genus Fagopyrum.Furthermore,our analyses indicated that sampled woody genera of the family Polygonaceae are polyphyletic.Our study provides strong evidence that the woody Parapteropyrum tibeticum,which is distantly related to woody genera sampled here,should be taxonomically placed under Fagopyrum as Fagopyrum tibeticum.

An ancient whole-genome duplication event and its contribution to flavor compounds in the tea plant (Camellia sinensis)

Tea,coffee,and cocoa are the three most popular nonalcoholic beverages in the world and have extremely high economic and cultural value.The genomes of four tea plant varieties have recently been sequenced,but there is some debate regarding the characterization of a whole-genome duplication(WGD)event in tea plants.Whether the WGD in the tea plant is shared with other plants in order Ericales and how it contributed to tea plant evolution remained unanswered.Here we re-analyzed the tea plant genome and provided evidence that tea experienced only WGD event after the core-eudicot whole-genome triplication(WGT)event.This WGD was shared by the Polemonioids-Primuloids-Core Ericales(PPC)sections,encompassing at least 17 families in the order Ericales.In addition,our study identified eight pairs of duplicated genes in the catechins biosynthesis pathway,four pairs of duplicated genes in the theanine biosynthesis pathway,and one pair of genes in the caffeine biosynthesis pathway,which were expanded and retained following this WGD.Nearly all these gene pairs were expressed in tea plants,implying the contribution of the WGD.This study shows that in addition to the role of the recent tandem gene duplication in the accumulation of tea flavor-related genes,the WGD may have been another main factor driving the evolution of tea flavor.

Overexpression of PvWOX3a in switchgrass promotes stem development and increases plant height

Switchgrass(Panicum virgatum L.)is an important perennial,noninvasive,tall ornamental grass that adds color and texture to gardens and landscapes.Moreover,switchgrass has been considered a forage and bioenergy crop because of its vigorous growth,low-input requirements,and broad geography.Here,we identified PvWOX3a from switchgrass,which encodes a WUSCHEL-related homeobox transcription factor.Transgenic overexpression of PvWOX3a in switchgrass increased stem length,internode diameter,and leaf blade length and width,all of which contributed to a 95%average increase in dry weight biomass compared with control plants.Yeast one-hybrid and transient dual-luciferase assays showed that PvWOX3a can repress the expression of gibberellin 2-oxidase and cytokinin oxidase/dehydrogenase through apparently direct interaction with their promoter sequences.These results suggested that overexpression of PvWOX3a could increase gibberellin and cytokinin levels in transgenic switchgrass plants,which promotes cell division,elongation,and vascular bundle development.We also overexpressed PvWOX3a in a transgenic miR156-overexpressing switchgrass line that characteristically exhibited more tillers,thinner internodes,and narrower leaf blades.Double transgenic switchgrass plants displayed significant increases in internode length and diameter,leaf blade width,and plant height but retained a tiller number comparable to that of plants expressing miR156 alone.Ultimately,the double transgenic switchgrass plants produced 174%more dry-weight biomass and 162%more solubilized sugars on average than control plants.These findings indicated that PvWOX3a is a viable potential genetic target for engineering improved shoot architecture and biomass yield of horticulture,fodder,and biofuel crops.

Identification and characterization of short tandem repeats in the Tibetan macaque genome based on resequencing data

The Tibetan macaque, which is endemic to China, is currently listed as a Near Endangered primate species by the International Union for Conservation of Nature （IUCN）（2017）. Short tandem repeats （STRs） refer to repetitive elements of genome sequence that range in length from 1-6 bp. They are found in many organisms and are widely applied in population genetic studies. To clarify the distribution characteristics of genome-wide STRs and understand their variation among Tibetan macaques, we conducted a genome-wide survey of STRs with next-generation sequencing of five macaque samples. A total of 1 077 790 perfect STRs were mined from our assembly, with an N50 of 4 966 bp. Mono-nucleotide repeats were the most abundant, followed by tetra- and di-nucleotide repeats. Analysis of GC content and repeats showed consistent results with other macaques. Furthermore, using STR analysis software （IobSTR）, we found that the proportion of base pair deletions in the STRs was greater than that of insertions in the five Tibetan macaque individuals （P〈0.05, t-test）. We also found a greater number of homozygous STRs than heterozygous STRs （P〈0.05, t-test）, with the Emei and Jianyang Tibetan macaques showing more heterozygous loci than Huangshan Tibetan macaques. The proportion of insertions and mean variation of alleles in the Emei and Jianyang individuals were slightly higher than those in the Huangshan individuals, thus revealing differences in STR allele size between the two populations The polymorphic STR loci identified based on the reference genome showed good amplification efficiency and could be used to study population genetics in Tibetan macaques. The neighbor-joining tree classified the five macaques into two different branches according to their geographical origin, indicating high genetic differentiation between the Huangshan and Sichuan populations. We elucidated the distribution characteristics of STRs in the Tibetan macaque genome and provided an effective method for screening polymorphic STRs. Our results also lay a foundation for future genetic variation studies of macaques.

Reproduction and genetic diversity of Juniperus squamata along an elevational gradient in the Hengduan Mountains

Elevation plays a crucial factor in the distribution of plants,as environmental conditions become increasingly harsh at higher elevations.Previous studies have mainly focused on the effects of large-scale elevational gradients on plants,with little attention on the impact of smaller-scale gradients.In this study we used 14 microsatellite loci to survey the genetic structure of 332 Juniperus squamata plants along elevation gradient from two sites in the Hengduan Mountains.We found that the genetic structure(single,clonal,mosaic)of J.squamata shrubs is affected by differences in elevational gradients of only 150 m.Shrubs in the mid-elevation plots rarely have a clonal or mosaic structure compared to shrubs in lower-or higher-elevation plots.Human activity can significantly affect genetic structure,as well as reproductive strategy and genetic diversity.Sub-populations at mid-elevations had the highest yield of seed cones,lower levels of asexual reproduction and higher levels of genetic diversity.This may be due to the trade-off between elevational stress and anthropogenic disturbance at mid-elevation since there is greater elevational stress at higher-elevations and greater intensity of anthropogenic disturbance at lower-elevations.Our findings provide new insights into the finer scale genetic structure of alpine shrubs,which may improve the conservation and management of shrublands,a major vegetation type on the Hengduan Mountains and the Qinghai-Tibet Plateau.

A New Species of Trimeresurus Lacépède, 1804(Squamata: Viperidae) from Southwestern China, Vietnam, Thailand and Myanmar

The pit vipers of the genus Trimeresurus Lacépède, 1804 is one of the largest groups of Asian snakes, distributed from India to China and Indonesia. Recent surveys in Jiangcheng and Simao, Yunnan Province, China resulted in a new species previously allocated to T. albolabris. Combining morphological and molecular data, we describe it as Trimeresurus guoi sp. nov. The new species morphologically differs from T. albolabris in the yellow green ventral color;an indistinct ventrolateral line;the a bsence of a postocular stripe;the firebrickred iris;a dark red stripe on dorsal tail;hemipenes with relatively weak sparse papillae, reaching 23 rd subcaudal when unextruded. Molecularly, the new species forms a clearly divergent lineage(BPP 1.00/UFB 100). Uncorrected pairwise distances of mitochondrial gene Cyt b between the new species and other known species of the subgenus Trimeresurus range from 0.052(T. albolabris) to 0.071(T. insularis).

Sex-biased genes and metabolites explain morphologically sexual dimorphism and reproductive costs in Salix paraplesia catkins

Dioecious species evolved from species with monomorphic sex systems in order to achieve overall fitness gains by separating male and female functions.As reproductive organs,unisexual flowers have different reproductive roles and exhibit conspicuous sexual dimorphism.To date,little is known about the temporal variations in and molecular mechanisms underlying the morphology and reproductive costs of dioecious flowers.We investigated male and female flowers of Salix paraplesia in three flowering stages before pollination(the early,blooming and late stages)via transcriptional sequencing as well as metabolite content and phenotypic analysis.We found that a large number of sex-biased genes,rather than sex-limited genes,were responsible for sexual dimorphism in S.paraplesia flowers and that the variation in gene expression in male flowers intensified this situation throughout flower development.The temporal dynamics of sex-biased genes derived from changes in reproductive function during the different flowering stages.Sexually differentiated metabolites related to respiration and flavonoid biosynthesis exhibited the same bias directions as the sex-biased genes.These sex-biased genes were involved mainly in signal transduction,photosynthesis,respiration,cell proliferation,phytochrome biosynthesis,and phenol metabolism;therefore,they resulted in more biomass accumulation and higher energy consumption in male catkins.Our results indicated that sex-biased gene expression in S.paraplesia flowers is associated with different reproductive investments in unisexual flowers;male flowers require a greater reproductive investment to meet their higher biomass accumulation and energy consumption needs.

Relationship between stand characteristics and soil properties of two typical forest plantations in the mountainous area of Western Sichuan, China

There is uncertainty and limited knowledge regarding stand characteristics and soil properties of middle-aged pure forest plantations in the mountainous area of Western Sichuan. Plantation forests are almost exclusively planted as monocultures in the Pengzhou forest farm in the western mountainous area of Sichuan Province. This study aimed to assess the spatial and ecological characteristics of middle-aged Cunninghamia lanceolata(Lamb.) Hook. and Cryptomeria fortunei Hooibr. in the Pengzhou forest farm. The relationships and differences between stand growth characteristics and forest soil composition were assessed on the two forests planted simultaneously within the same area and exposed to the same environmental conditions. Cr. fortunei grew sparse, and slower than Cun. lanceolata. Principal component analysis indicated that the soil properties in the Cr. fortunei plantation were better than those in the Cun. lanceolata plantation. Redundancy analysis revealed that the differences in stand structure were affected significantly by the total nitrogen content and pH value. Thus, we propose that Cr. fortunei is planted for priority consideration in the subtropical high mountain area. Further, tending operations and application of fertilizers need to be conducted in Cun. lanceolata forests. Based on theoretical and experimental data, the present study explains why local farmers are more willing to plant Cr. fortunei, and thus provides a useful theoretical reference for the development of sustainable plantations in the future.

Sex But Not Altitude, Modulates Phenotypic Covariations Between Growth and Physiological Traits in Adult Asiatic Toads

The pace-of-life syndrome(POLS) hypothesis predicts that most variation in life history, physiology,and behavior among individuals, popula tions, and species falls along a continuum from slow to fast pace of life. While there is evidence for climatic gradientmediated POLS patterns among species, this approach has rarely been explicitly used to study POLS patterns among-and within-populations. In addition, the roles of sex in POLS evolution among-or within-populations are largely unknown. In this study, we investigated the effects of altitudinal gradient and sex on the covariations between growth rate and several physiological traits closely associated with POLS(blood glucose, baselineand stress-induced glucocorticoids(GCs), hemolysis and hemagglutination) in the Asiatic toad Bufo gargarizans.Contrary to our expectation, altitudinal gradient had no influence on the covariations between growth rate and physiological traits, neither at the among-nor withinpopulation level, indicating that these trait integrations have similar fitness payoffs across hierarchical levels.In contrast, we found evidence for sex-specific POLS composition: there was a negative covariance structure between growth rate and baseline GCs-but only in females, and a positive covariance structure between growth rate and baseline GCs-but only in females, and a positive covariance structure between growth rate and hemagglutination-but only in males. This observation indicates that these trait associations differ dramatically in advancing fitness for each sex, and supports the idea that sex-specific POLS composition could evolve in species in which the reproductive roles largely differ between the sexes.

Behavioral and Neurogenomic Responses to Acoustic and Visual Sexual Cues are Correlated in Female Torrent Frogs

Diverse a nimal species use multimodal communica tion signals to coordina te reproductive behavior.Despite active research in this field,the brain mechanisms underlying multimodal communication remain poorly understood.Similar to humans and many mammalian species,anurans often produce auditory signals accompanied by conspicuous visual cues(e.g.,vocal sac inflation).In this study,we used video playbacks to determine the role of vocal-sac inflation in little torrent frogs(Amolops torrentis).Then we exposed females to blank,visual,auditory,and audiovisual stimuli and analyzed whole brain tissue gene expression changes using RNAseq.The results showed that both auditory cues(i.e.,male advertisement calls)and visual cues were attractive to female frogs,although auditory cues were more attractive than visual cues.Females preferred simultaneous bimodal cues to unimodal cues.The hierarchical clustering of differentially expressed genes showed a close relationship between neurogenomic states and momentarily expressed sexual signals.We also found that the Gene Ontology terms and KEGG pathways involved in energy metabolism were mostly increased in blank contrast versus visual,acoustic,or audiovisual stimuli,indicating that brain energy use may play an important role in response to these stimuli.In sum,behavioral and neurogenomic responses to acoustic and visual cues are correlated in female little torrent frogs.

A New Species of the Genus Rhabdophis Fitzinger,1843(Squamata:Colubridae)in Southwestern Sichuan,China

The genus Rhabdophis is a group of widely distributed snakes with more than 20 species.Recent field surveys uncovered a species in southwestern China,which has long been considered as R.pentasupralabialis.Combined molecular and morphological analyses revealed it as a new species Rhabdophis chiwen sp.nov.Based on 12 specimens,this new species is distinguished by the following characters:1)dorsal body saddlebrown,dorsal scales typically with black margins forming spots and stripes,the margin of the outer row forming two faint dorsolateral black cross-bars alongside body;2)ventral scales 151–159,the outer margin of ventral scales and several lateral rows of dorsal scales forming ventrolateral longitudinal brownish-red coloration,with faint black spots in the middle of ventral scales;3)a black oblique stripe present below eyes,often with a black spot between the 2 nd and 3 rd supralabial and a black stripe on the 5 th supralabial;4)eyes dark khaki,pupils black;5)infralabials usually 7,the first four in contact with anterior chin-shields;6)temporal scales 1+1;7)dorsal scales in 15 rows,feebly keeled except the outer 1–2 rows;8)anal scale divided;subcaudals 45–59;9)preocular 1 and postoculars 3(occasionally 2);10)body medium-sized(snout-vent length:adult males 404–431 mm,adult females 409–476 mm);11)tail moderate(tail length/total length in adult males 0.205–0.238,in adult females0.172–0.193).With the discovery of this new species,the total number of species in genus Rhabdophis is 28 with 12 th species known to occur in China.