Temperate Asia Research Articles

Lespedeza homoloba enhances the immunosuppressive milieu of adipose tissue and suppresses fasting blood glucose.

Immune cells migrate to hypertrophied adipocytes and release proinflammatory cytokines, leading to adipocyte dysfunction and diabetes. Numerous species of Lespedeza, which are members of the plant family Fabaceae and distributed primarily in temperate Asia and North America, exhibit binding to peroxisome proliferator-activated receptor (PPAR) γ, a target nuclear receptor for treating diabetes. Therefore, the present study aimed to determine which species of Lespedeza plants exert an anti-inflammatory effect in adipose tissue and suppression of blood glucose increase through PPARγ ligand and radical scavenging activity. PPARγ binding and DPPH radical scavenging assays of L. homoloba (LH), L. thunbergii (LT), L. maximowiczii (LM) and L. thunbergii (LT) were performed. LH and LT showed significant ligand activity towards PPARγ and notable radical scavenging activity. LH exhibited a stronger DPPH radical scavenging activity than LT and thus was measured adiponectin secretion from 3T3-L1-derived adipocytes and IL-10 secretion from murine splenocytes. LH increased the adiponectin and the IL-10 secretions. In flow cytometric analysis, BALB/c male mice administered LH exhibited an increase in regulatory T cells (Tregs) and cytotoxic T lymphocyte-associated protein (CTLA)-4+ Tregs as well as a decrease in T helper (Th)17, Th17/Treg ratio and CD8+ and CD4+ T cells in subcutaneous adipose tissue. Conversely, in the spleen, LH decreased Tregs and increased Th17 cells, Th17/Treg ratio and CD4+ and CD8+ T cells. These findings indicated that LH activated immunoreaction in the spleen and Treg cells that migrate to subcutaneous adipose tissue may suppress inflammation. In fasting blood glucose and adiponectin assays, LH-exposed mice exhibited suppression of fasting glucose levels. Therefore, LH may prevent type 2 diabetes by suppressing adipose tissue inflammation.

Mapping ignorance to uncover shortfalls in the knowledge on global Orthoptera distribution

Understanding the spatiotemporal distribution of species is fundamental for ecology, evolution and conservation. However, this and other aspects of biodiversity knowledge suffer from shortcomings and biases. Quantifying and mapping biodiversity knowledge shortfalls is therefore crucial to ascertain the current quality and completeness of biodiversity data, prioritize sites for (re)sampling, or plan conservation interventions. Here, we compile a comprehensive dataset of Orthoptera occurrences, and use it to create a global ‘ignorance map’ based on taxonomic, survey and temporal completeness, and on survey and temporal evenness of the inventories. We hypothesize that knowledge of Orthopteran biodiversity is relatively poorer in tropical regions compared to temperate regions, and in the south compared to the northern hemisphere. Due to biocultural factors, we expect regions in the tropics and the Global South to have lower levels of completeness and evenness in time and space for all the studied aspects of biodiversity information. Our findings show gaps in the knowledge of orthopteran distributions, which are characterized by low survey and temporal evenness in tropical regions, but also in many temperate regions (e.g., most of the countries in temperate Asia). The combination of multiple dimensions of biodiversity knowledge (taxonomic, spatial and temporal) reveals that biogeographic interpretations based on only one component can lead to an illusion of completeness. We believe that the novel framework used in our study can guide future research towards building more accessible maps of biogeographical ignorance for entire groups.

Kazakhstan Has an Unexpected Diversity of Medicinal Plants of the Genus Acorus (Acoraceae) and Could Be a Cradle of the Triploid Species A. calamus.

The Acorus calamus group, or sweet flag, includes important medicinal plants and is classified into three species: A. americanus (diploid), A. verus (tetraploid), and A. calamus (sterile triploid of hybrid origin). Members of the group are famous as components of traditional Indian medicine, and early researchers suggested the origin of the sweet flag in tropical Asia. Subsequent research led to an idea of the origin of the triploid A. calamus in the Amur River basin in temperate Asia, because this was the only region where both diploids and tetraploids were known to co-occur and be capable of sexual reproduction. Contrary to this hypothesis, triploids are currently very rare in the Amur basin. Here, we provide the first evidence that all three species occur in Kazakhstan. The new records extend earlier data on the range of A. verus for c. 1800 km. Along the valley of the Irtysh River in Kazakhstan and the adjacent Omsk Oblast of Russia, A. verus is recorded in the south, A. americanus in the north, and A. calamus is common in between. We propose the Irtysh River valley as another candidate for a cradle of the triploid species A. calamus. It is possible that the range of at least one parent species (A. americanus) has contracted through competition with its triploid derivative species, for which the Irtysh River floods provide a tool for downstream range expansion. We refine our earlier data and show that the two parent species have non-overlapping ranges of variation in a quantitative metric of leaf aerenchyma structure.

Seed dormancy types and germination response of 15 plant species in temperate montane peatlands.

Despite their crucial role in determining the fate of seeds, the type and breaking mode of seed dormancy in peatland plants in temperate Asia with a continental monsoon climate are rarely known. Fifteen common peatland plant species were used to test their seed germination response to various dormancy-breaking treatments, including dry storage (D), gibberellin acid soaking (GA), cold stratification (CS), warm followed cold stratification (WCS), GA soaking + cold stratification (GA + CS) and GA soaking + warm followed cold stratification (GA + WCS). Germination experiment, viability and imbibition test, and morphological observation of embryos were conducted. Of the 15 species, nine showed physiological dormancy (PD), with non-deep PD being the dominant type. Four species, Angelica pubescens, Cicuta virosa, Iris laevigata, and Iris setosa exhibited morphophysiological dormancy. Two species, Lycopus uniflorus and Spiraea salicifolia, demonstrated nondormancy. Overall, the effect hierarchy of dormancy-breaking is: CS > GA > WCS > GA + CS > D > GA + WCS. Principal component analysis demonstrated that seed traits, including embryo length: seed length ratio, seed size, and monocot/eudicot divergence, are more likely to influence seed dormancy than environmental factors. Our study suggests that nearly 90% of the tested peatland plant species in the Changbai Mountains demonstrated seed dormancy, and seed traits (e.g. embryo-to-seed ratio and seed size) and abiotic environmental factors (e.g. pH and temperature seasonality) are related to germination behavior, suggesting seed dormancy being a common adaptation strategy for the peatland plants in the temperate montane environment.

A global surface CO2 flux dataset (2015–2022) inferred from OCO-2 retrievals using the GONGGA inversion system

Abstract. Accurate assessment of the size and distribution of carbon dioxide (CO2) sources and sinks is important for efforts to understand the carbon cycle and support policy decisions regarding climate mitigation actions. Satellite retrievals of the column-averaged dry-air mole fractions of CO2 (XCO2) have been widely used to infer spatial and temporal variations in carbon fluxes through atmospheric inversion techniques. In this study, we present a global spatially resolved terrestrial and ocean carbon flux dataset for 2015–2022. The dataset was generated by the Global ObservatioN-based system for monitoring Greenhouse GAses (GONGGA) atmospheric inversion system through the assimilation of Orbiting Carbon Observatory-2 (OCO-2) XCO2 retrievals. We describe the carbon budget, interannual variability, and seasonal cycle for the global scale and a set of TransCom regions. The 8-year mean net biosphere exchange and ocean carbon fluxes were −2.22 ± 0.75 and −2.32 ± 0.18 Pg C yr−1, absorbing approximately 23 % and 24 % of contemporary fossil fuel CO2 emissions, respectively. The annual mean global atmospheric CO2 growth rate was 5.17 ± 0.68 Pg C yr−1, which is consistent with the National Oceanic and Atmospheric Administration (NOAA) measurement (5.24 ± 0.59 Pg C yr−1). Europe has the largest terrestrial sink among the 11 TransCom land regions, followed by Boreal Asia and Temperate Asia. The dataset was evaluated by comparing posterior CO2 simulations with Total Carbon Column Observing Network (TCCON) retrievals as well as Observation Package (ObsPack) surface flask observations and aircraft observations. Compared with CO2 simulations using the unoptimized fluxes, the bias and root mean square error (RMSE) in posterior CO2 simulations were largely reduced across the full range of locations, confirming that the GONGGA system improves the estimates of spatial and temporal variations in carbon fluxes by assimilating OCO-2 XCO2 data. This dataset will improve the broader understanding of global carbon cycle dynamics and their response to climate change. The dataset can be accessed at https://doi.org/10.5281/zenodo.8368846 (Jin et al., 2023a).

CamTrapAsia: A dataset of tropical forest vertebrate communities from 239 camera trapping studies.

Information on tropical Asian vertebrates has traditionally been sparse, particularly when it comes to cryptic species inhabiting the dense forests of the region. Vertebrate populations are declining globally due to land-use change and hunting, the latter frequently referred as "defaunation." This is especially true in tropical Asia where there is extensive land-use change and high human densities. Robust monitoring requires that large volumes of vertebrate population data be made available for use by the scientific and applied communities. Camera traps have emerged as an effective, non-invasive, widespread, and common approach to surveying vertebrates in their natural habitats. However, camera-derived datasets remain scattered across a wide array of sources, including published scientific literature, gray literature, and unpublished works, making it challenging for researchers to harness the full potential of cameras for ecology, conservation, and management. In response, we collated and standardized observations from 239 camera trap studies conducted in tropical Asia. There were 278,260 independent records of 371 distinct species, comprising 232 mammals, 132 birds, and seven reptiles. The total trapping effort accumulated in this data paper consisted of 876,606 trap nights, distributed among Indonesia, Singapore, Malaysia, Bhutan, Thailand, Myanmar, Cambodia, Laos, Vietnam, Nepal, and far eastern India. The relatively standardized deployment methods in the region provide a consistent, reliable, and rich count data set relative to other large-scale pressence-only data sets, such as the Global Biodiversity Information Facility (GBIF) or citizen science repositories (e.g., iNaturalist), and is thus most similar to eBird. To facilitate the use of these data, we also provide mammalian species trait information and 13 environmental covariates calculated at three spatial scales around the camera survey centroids (within 10-, 20-, and 30-km buffers). We will update the dataset to include broader coverage of temperate Asia and add newer surveys and covariates as they become available. This dataset unlocks immense opportunities for single-species ecological or conservation studies as well as applied ecology, community ecology, and macroecology investigations. The data are fully available to the public for utilization and research. Please cite this data paper when utilizing the data.

Diploids and tetraploids of Acorus (Acoraceae) in temperate Asia are pseudocryptic species with clear differences in micromorphology, DNA sequences and distribution patterns, but shared pollination biology

AbstractCommonly considered bispecific, Acorus is one of the most phylogenetically isolated angiosperm genera that forms the order Acorales sister to the rest of the monocots. The Acorus calamus group is widely distributed in the Holarctic regions of Eurasia and America and has strong medicinal and other practical uses since prehistoric times. Earlier studies interpreted native diploids and invasive triploids occurring in North America as two species that differed in morphology and distribution ranges. In contrast, diploids, triploids, and tetraploids occurring in Eurasia are commonly interpreted as one species because they reportedly cannot be distinguished in collections. We resolve the controversy over taxonomic concepts between Eurasia and America and provide the first detailed multidisciplinary account of Acorus in temperate Asia. We used plastid and nuclear markers, leaf anatomy, seed micromorphology, pollen stainability, flow cytometry, and direct chromosome counts. Diploids and tetraploids show stable molecular and micromorphological differences. Triploids are their sterile hybrids, with the plastid genome inherited from the diploid parent. Diploids of America and Asia tend to differ in leaf characters. Coadaptative coexistence with pollinating beetles Platamartus jakowlewi and Sibirhelus corpulentus (Kateretidae) is conserved between diploids and tetraploids and over a distance of 4700 km between Japan and Western Siberia. Diploids are self‐compatible and can set seeds in the absence of kateretid beetles. Tetraploids are self‐incompatible and/or cannot set seeds in the absence of Platamartus and Sibirhelus. Diploids (A. americanus) and tetraploids (A. verus) are two biological species; the former has two subspecies. Acorus calamus should be restricted to triploids; it apparently first evolved in temperate Asia. Diploids mostly occur in much cooler climates than triploids and tetraploids. Accessions of A. verus and A. calamus from tropical Asia are apparently derived from ancient introductions. Our data provide a new framework for the pharmacological use of Acorus.

Spatial phylogenetics of Fagales: Investigating drivers of temperate forest distributions

AbstractAimQuantifying the phylogenetic diversity of temperate trees is essential for understanding the processes that have shaped the modern distribution of temperate broadleaf forest and other major forest biomes. Here, we focus on Fagales, an iconic member of forests worldwide, to uncover global diversity and endemism patterns and investigate the distribution of root nodule symbiosis (RNS), an important morphological specialisation in this clade, as a key factor behind these patterns.LocationGlobal.TaxonFagales.MethodsWe combined phylogenetic data covering 60.2% of living species, fine‐scale distribution models covering 90% of species, and nodulation data covering all species to investigate the distribution of species richness and phylogenetic diversity at fine spatial scales compared to the distribution of RNS. We identify abiotic environmental factors associated with RNS and with Fagales diversity in general.ResultsWe find the highest species richness in temperate east Asia, eastern North America, and equatorial montane regions of Asia and Central America. By contrast, relative phylogenetic diversity (RPD) is highest at higher latitudes, where RNS also predominates. We found a strong spatial structuring of regionalisations of Fagales floras, reflecting distinct Northern and Southern Hemisphere floras (except a unique Afro‐Boreal region), each with distinct RNS‐environment relationships.Main ConclusionsAlthough species richness and phylogenetic regionalisation for Fagales accord well with traditional biogeographic concepts for temperate forests, this is not the case for RPD. RNS is almost universal in the highest RPD regions, which may reflect ecological filtering promoting RNS in these regions. Our results highlight the utility of global‐scale, clade‐specific spatial phylogenetics and its utility for understanding drivers of diversity in species‐rich clades.

Wet canopy photosynthesis in a temperate Japanese cypress forest.

This study aimed to reveal the mechanism and significance of wet canopy photosynthesis during and after rainfall in temperate coniferous ecosystems by evaluating the influence of abaxial leaf interception on wet canopy photosynthesis. We used the eddy covariance method in conjunction with an enclosed-path gas analyser to conduct continuous ecosystem CO2 flux observations in a Japanese cypress forest within the temperate Asian monsoon area over 3years. The observation shows that wet-canopy CO2 uptake predominantly occurred during the post-rainfall canopy-wet period rather than the during-rainfall period. Then, the measured canopy-wet net ecosystem exchange was compared with the soil-vegetation-atmosphere transfer multilayer model simulations under different parameter settings of the abaxial (lower) leaf surface wet area ratio. The multilayer model predicted net ecosystem exchange most accurately when it assumed the wet area ratio of the abaxial surface was 50% both during and after rainfall. For the wet canopy both during and after rainfall, the model overestimated CO2 uptake when it assumed no abaxial interception in the simulation, but underestimated CO2 uptake when it assumed that the entire abaxial leaf surface was wet. These results suggest that the abaxial surface of the Japanese cypress leaf is only partly wet to maintain stomatal openness and a low level of photosynthesis. These results allow for an evaluation of the effect of rainfall on forest carbon circulation under a changing climate, facilitating an improvement of ecosystem carbon exchange models.

The only species of Calvisia (Phasmatodea, Necrosciinae) from China, with a new synonymy and additional descriptions.

Calvisia is a colorful winged stick insect genus consisting of 6 subgenera and 44 species widely distributed in temperate and tropical Asia. C. medogensis syn. nov. was discovered in Mdog, Xizang (Tibet), China and is so far the only species recorded from China. We here propose that C. medogensis syn. nov. is a synonym of C. fuscoalata after checking type specimens of both species. New materials studied are deposited in Yunnan Agricultural University, China (YNAU).

A Comprehensive Review on the Traditional Uses, Phytochemical Compositions and Pharmacological Properties of an Ethnomedicinal Herb, Paederia foetida

Background:: Paederia foetida L. (Family – Rubiaceae) is a common herb found available in the temperate and tropical Asia. The ethnomedicinal applications of this plant are widely elaborated In Chinese Traditional Medicine, Ayurveda, and other ancient scriptures throughout the world. Different ethnic groups use this plant in the treatment of alimentary and digestive disorders, bone related diseases like rheumatoid arthritis, bone fractures as well as in the ailments of diabetes, coughs, asthma, itches, wounds, body ache, toothache, cancer etc. Objectives:: This comprehensive review aims to provide an insightful understanding of traditional uses, chemical composition, and pharmacological properties of P. foetida (from 1976 up to 2023), which may provide a foundation for further study and for the proper utilization of P. foetida resources. Methods:: Literature survey was conducted using known databases and the relevant keywords. Results:: P. foetida has been widely used in Chinese traditional medicine (CTM) for the treatment of dyspepsia, jaundice, pains, diarrhea and others. Several ethnic groups throughout the world used this plant to cure common health complaints namely, abdominal pain, gastritis, dysentery, diarrhoea, constipation, joint pain, etc. A total of 24 bioactive phytocompounds, such as asperuloside, paederosidic acid, sitosterols, stigmasterol, campesterol, ellagic acid, iridoids, ursolic acid, epifriedelinol, and others are reported to possess antiulcer, antidiarrheal, antihyperglycemic, antioxidant, antitussive, anthelmintic, and hepatoprotective activities. Conclusion:: The present review not only summarizes the alternative approaches using this herb by ethnic people for treating various disorders, but also focuses on the latest scientific investigations to elucidate different bioactivities of this plant, thereby facilitating the understanding of its correlation with contemporary pharmacology. However, till date, very few studies elucidated the biological properties of these phytochemicals that were isolated exclusively from this particular plant. Moreover, the correlation between phytocompounds from P. foetida and its pharmacological activities aiming towards clinical drug development is still lacking. Finally, further research should be oriented towards determining the optimal dosage and toxicological limits, and thereby providing guidance for clinical applications.

Psyllids in Natural Habitats as Alternative Resources for Key Natural Enemies of the Pear Psyllids (Hemiptera: Psylloidea).

The pear psyllids (Cacopsylla spp.; Psylloidea) comprise ~24 species of sap-feeding insects distributed in Europe, temperate Asia, and (as introductions) in the Americas. These pear-specialized insects are among the most damaging and difficult to control pests in orchards. Biological control increasingly is being used to replace or partially replace insecticidal management of pear psyllids. Many key natural enemies of pear psyllids regularly occur in non-orchard habitats on native plants. The presence of beneficial species both in orchard and non-orchard habitats (here referred to as "spillover") has prompted suggestions that native plants and their associated psyllids should be conserved as alternative resources for natural enemies of pear psyllids. The expectation is that the natural enemies will move from those habitats into psyllid-infested orchards. This review shows that psyllids in native habitats are important resources for several key predators and parasitoids of pear psyllids. These resources are critical enough that some beneficials exhibit an almost nomadic existence as they move between plant species, tracking the seasonal appearance and disappearance of psyllid species. In contrast, other natural enemies show minimal or no spillover between orchard and non-orchard habitats, which likely is evidence that they exhibit limited movement at best between orchard and non-orchard habitats. To show conclusively that spillover also indicates that a beneficial species disperses between native habitats and orchards requires difficult research on insect movement. This review concludes with a brief discussion of these difficulties and possible solutions.

COMPARATIVE ANALYSIS OF THE ANATOMICAL AND MORPHOLOGICAL FEATURES OF RHEUM TATARICUM L. PLANTS FROM DIFFERENT ECOPOPULATIONS

There are about 60 species of the genus Rheum L. (Polygonaceae) distributed mainly in temperate and subtropical Asia, with the largest number (38 species, including 19 endemics) recorded in China. All species of the genus are used as medicinal plants. According to modern pharmacology, the most important property of the rhubarb root is regulation of the stomach and intestine function, due to its laxa-tive effect; rhubarb also has antipyretic properties and antioxidant activity. The high content of dietary fibers provides protection against cardiovascular diseases, and vitamin K is valuable for the prevention of osteoporosis. However, the active ingredients and their mechanism of action have not been sufficiently studied.Rheum tataricum L., known for its high resistance to drought, salinity, and lack of nutrients is the least studied species of wild rhubarb. The whole plant, and especially the leaves, contains several toxic compounds, in particular anthraquinone glycosides and calcium oxalate crystals. Here we present the results of a comparative analysis of the anatomical and morphological structure of Rh. tataricum plants from ecopopulations growing in the Balkhash and Karatal districts of the Almaty region. We identified the differences due to the weather and climatic conditions of the ecopopulations. It is important to note that many idioblasts containing calcium oxalate were found in the rhizomes of Rh. tataricum, which prevent animals from eating plants and getting poisoned. The number of idioblasts in the central circle of the Rh. tataricum rhizome was smaller in the Balkhash district than in the Karatal district, while the idioblasts were larger in size in the former district. The medicinal and nutritional value of Rh. tataricum growing in a semi-desert environment indicates a high potential of the species in plant breeding, medicine, and as a food source.

Therapeutic Effects of Nettle Leaf: An Indigenous Vegetable

Stinging Nettle (Urtica dioica L.; family Urticaceae) is extensively used species by traditional societies of Temperate and Tropical Asia, Europe, Northern America and Northern Africa. As food, the species shows nutritional as well as immunity modulating benefits. It has shown positive benefits for treating various diseases, such as BPH, diabetes, anemia, asthma, hypertension, kidney problem, cancer, etc.; although these claims are based on different doses, followed by type and duration of intervention. There is a need to take-up more coordinated researches and validation studies in future so that applicability of nettle could be established properly against various diseases as well as proper quality control and toxicological investigations is required to assure the stability and safety of the clinical uses.

The complete chloroplast genome of Porella gracillima Mitt. (Porellaceae) and phylogenetic relationships to other bryophytes

Porella gracillima Mitt. (Jungermanniidae, Porellaceae), a bryophyte is widespread in temperate Asia and North America. In Korea, P. gracillima is mainly observed in shaded and dried rocks or tree trunks on mountains. Here, we determined the complete chloroplast (cp) genome sequence of P. gracillima to provide useful genetic information in the phylogenetic relationship, phylogeographic history, and conservation of the species. The complete cp genome of P. gracillima was assembled using NGS Illumina HiSeqX platform. The cp genome was 121,867 bp in length (GC contents, 33.7%) and showed a typical quadripartite structure, consisting of a large single copy (LSC) of 83,406 bp, a small single copy (SSC) of 19,692 bp, and two inverted repeats (IRs) of 9,385 bp. Phylogenetic analysis shows that Porellaceae was a sister group of Radulaceae, which agrees with the findings of the previous phylogenetic studies. Our cp genome data of P. gracillima may contribute to a better understanding of the evolution of the Porella in Porellaceae and will help to infer its molecular identification, thereby providing a guideline for conservation.

Thermal Stress and Adult Fitness in a Drosophila suzukii Neotropical Propagule.

Drosophila suzukii (Matsumura 1931) is a cosmopolitan horticultural pest originally from temperate East Asia; yet, its recent introduction in southeast and central Brazil raises the possibility it might expand into warmer climatic zones. In theoretical terms, the adaptive potential of invasive species can be impaired by the lack of genetic variation, but, on the other hand, phenotypic plasticity might play an important role in the adaptation to the new environment. In this context, we investigated the effects of temperature variation (18°C, 22°C, and 28°C) on fitness traits and size of male reproductive organs (accessory glands and testis) in a natural D. suzukii population recently introduced in the neotropical region. Development time decreased significantly with increasing temperature, but egg-to-adult survival was not affected, attaining rates around 50% for the three temperatures. Development at 28°C affected differentially adult male and female biological performance: males displayed higher mortality and severe and permanent reduction in offspring production, whereas females showed the same mortality as controls and a temporary decrease in offspring production, followed of a clear recovery. Finally, reproductive organs size in immature and mature males was affected by developmental temperature variation in the following ways. Testis length decreased with body size (i.e., at higher temperatures) and increased with maturation time after adult hatching, whereas for accessory glands there was no significant difference between different temperatures, resulting in proportionally larger glands for smaller body sizes. These results show differences in developmental dynamics of reproductive tract structures due to temperature variation.

Back to Linnaeus: Proper Botanical Naming of the Tetraploid Indian Acorus (Acoraceae), an Important Medicinal Plant

The basal monocot genus Acorus comprises essential oil-producing plants widely used in traditional medicine in various countries, including India. Acorus calamus sensu lato is a polyploid complex where the essential oil composition, to some extent, depends on the ploidy level. The literature recognizes diploids (in temperate Asia and North America), triploids (Asian in origin, naturalized elsewhere) and tetraploids (temperate to tropical Asia) at the rank of varieties of A. calamus. We show that the current use of the name A. calamus var. angustatus for the tetraploids is not properly justified. The earliest name based on the Asian material is A. calamus var. verus published in 1753 by Linnaeus. We justify the use of the Linnaean variety for tetraploids by selecting an epitype based on the material cultivated in Peninsular India, for which direct chromosome counts are provided. The name A. verus is available if the tetraploid cytotype is recognized at the species rank. We support earlier data on the importance of leaf anatomy for cytotype diagnostics in Acorus, but also show the limitations of the use of this approach. The growth pattern of the tropical Indian tetraploid material is discussed, and the evergreen nature of the accession studied here is documented. The exact chromosome number of the tetraploid Acorus requires further clarification. All metaphase plates examined here showed at least 44 chromosomes, but plates apparently showing more than 44 chromosomes were found as well. They may be explained by technical difficulties in counting chromosomes in Acorus. Alternatively, our data may indicate the occurrence of aneuploid mixoploidy.

Comparative effects of temperature and salinity on growth of four harmful Chattonella spp. (Raphidophyceae) from tropical Asian waters

In Asia, four harmful raphidophyte species, Chattonella malayana, C. marina, C. subsalsa, and C. tenuiplastida, coexist in the tropical waters but only C. marina was detected in temperate waters. This occurrence pattern pointed to a potentially distinct ecophysiological niche occupancy and possible species dispersion. The growth physiology of these species isolated from tropical Southeast Asia was investigated using unialgal cultures in ten temperatures (13.0–35.5°C) and five salinities (15–35) to better understand the factors driving their distribution. The highest maximum specific growth rates were observed in C. subsalsa (0.65 ± 0.01 d-1), followed by C. malayana (0.47 ± 0.03 d-1), C. marina (0.45 ± 0.02 d-1), and C. tenuiplastida (0.39 ± 0.01 d-1). Their optimal temperatures were 28.0, 30.5, 25.5, and 30.5°C, respectively, of which C. marina preferred colder water. C. subsalsa exhibited a wider growth temperature range (20.5–35.5°C), followed by C. marina (20.5–30.5°C), C. tenuiplastida (23.0–33.0°C), and C. malayana (25.5–33.0°C). Optimal salinities were similar between C. subsalsa and C. malayana (30), and between C. marina and C. tenuiplastida (25), but C. subsalsa and C. marina exhibited a similar growth salinity range of 15–35, while C. malayana and C. tenuiplastida was 20–35. High values of Fv/Fm were observed in C. subsalsa and C. marina (> 0.5) in all tested conditions, but Fv/Fm of C. malayana and C. tenuiplastida were significantly lower at 20.5°C. All four species achieved a maximum cell density of > 104 cells mL-1 in their optimal conditions. Optimal temperatures in C. subsalsa and C. marina were identical to previous reports. The high adaptability of C. subsalsa in various temperatures and salinities suggests its high competitiveness and bloom potential. The high adaptability of C. marina in colder waters compared to other species likely contributes to its wide distribution in the temperate Asian waters. The narrow temperature window of C. malayana and C. tenuiplastida suggests their endemicity and limited distribution in the tropical waters. This study provides evidence about the occurrences and bloom potential of Chattonella spp. in Asia, but the endemicity versus dispersion issue remains unresolved.

Taxonomy and multigene phylogeny of Pseudohydnum (Auriculariales, Basidiomycota)

Taxonomy of Pseudohydnum gelatinosum and its sister taxa is revised via morphological data and a four-gene dataset (ITS, nc LSU rDNA, TEF1, RPB1). Identity of P. gelatinosum and Tremellodon pusillus is re-established based on newly collected and sequenced material from their type localities. Pseudohydnum alienum from Europe; P. umbrosum from temperate East Asia; P. cystidiatum, P. meridianum, and P. placibile from Vietnam; and P. omnipavum from North America are described as new to science; P. translucens and P. brunneiceps from East Asia are redescribed. Most Pseudohydnum collections from North America belong to P. gelatinosum ssp. pusillum. A significant divergence of TEF1 sequences in P. gelatinosum is discussed.

Characterization of the complete chloroplast genome sequence of Limnophila sessiliflora Blume 1826 (Plantaginaceae)

Limnophila sessiliflora Blume 1826 is a perennial amphibious herb with ornamental and water purification value that is widespread in temperate and tropical Asia. In the present study, we sequenced, assembled, and annotated the complete chloroplast (cp) genome of L. sessiliflora. It is 152,395 bp in length, with a typical quadripartite structure, comprising a pair of inverted repeat regions (IRs; 25,545 bp), a large single-copy region (LSC; 83,163 bp), and a small single-copy (SSC; 18,142 bp) region. The whole cp genome contained 135 genes, including 89 protein-coding genes (PCGs), 38 transfer RNA (tRNA) genes, and eight ribosomal RNA (rRNA) genes. The maximum-likelihood (ML) phylogenetic analysis indicated that L. sessiliflora was closely related to the genera Bacopa and Scoparia in the tribe Gratioleae of Plantaginaceae. This cp genome provides a valuable genetic resource for phylogenetic study.