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Plants host diverse assemblages of fungi on their foliar tissues, both in internal compartments and on exterior surfaces. When plant distributions shift, they can move with their fungal associates (i.e., co‐introduction) or acquire new associates present in the novel environment (host‐jumping). The fungal communities that plants acquire influence a plant's ability to establish and spread in this new environment. Here, we aimed to assess whether invasive C. ciliaris hosts similar groups of fungi in its native and introduced ranges and to evaluate community overlap of fungi associated with foliar tissue of C. ciliaris and native and non‐native plants within the introduced range. In the introduced range, the majority of OTUs associated with C. ciliaris were not found in its native range, although 3.2% of OTUs were common to both ranges. Of these shared OTU, 77.6% were found on co‐occurring natives and non‐natives in the introduced range, whereas 22.4% were unique to C. ciliaris indicating a possible co‐introduction. Fungal communities within the introduced range contained a higher proportion of generalist symbionts and increased heterogeneity of foliar communities than in its native range. Within the introduced range, host phylogenetic distance explained more variation than native status. Our findings provide evidence that non‐natives acquire fungi opportunistically from their environment, although host and environmental filtering is present suggesting that successful invasive plants may be able to limit the effect of poor symbionts and select for better ones. Future experimental work will be needed to confirm the occurrence of host selection and identify its mechanisms. [ABSTRACT FROM AUTHOR]

Aeschynanthus pentatrichomatus sp. nov. (Gesneriaceae), a new species from the tropical lower montane rain forests of the Banao Protected Landscape in Luzon Island in the Philippines is described and illustrated. Morphologically, it is most similar to A. batesii in having glabrous vegetative parts, polysepalous calyx, and distinctly mottled internal corolla throat and lobes. However, it differs from this species in its smaller lamina, longer peduncle, smaller calyx lobes, whitish pink external corolla tube, and presence of five tufts of trichomes near the basal portion of the internal surface of the corolla tube. Aeschynanthus pentatrichomatus differs from A. philippinensis by its externally whitish pink, internally white corolla tube with mottled maroon markings throughout the limb and lobes, smaller calyx lobes, and internal surface of corolla tube with five tufts of trichomes basally. Aeschynanthus pentatrichomatus sp. nov. is the 33rd species of lipstick vines to be described in the Philippines. The new species is provisionally assessed as Critically Endangered (CR) following the IUCN criteria. [ABSTRACT FROM AUTHOR]

Dokdo is an island located in the easternmost part of Korea, which has high levels of biodiversity of birds and fish, especially marine invertebrates. However, the biodiversity of microalgae, especially diatoms (Bacillariophyta), is relatively unknown, despite their ecological importance as primary producers of the marine food web and bioindicators of environmental conditions associated with climate change. To understand the biodiversity of seaweed-associated diatoms from Dokdo, we collected macroalgae present at a depth 5–15 m by SCUBA diving on 17 October 2017. There were a large number of diatoms (over 130 species), even though it was a one-time survey. As it includes too many taxa to cover at once, voucher flora for other taxonomic groups will be provided through the continuous serial papers. This is the first series of seaweed-associated diatoms, with 26 species belonging to the subphyla Melosirophytina and Coscinodisophytina, and the class Mediophyceae. Among these, seven species including one new taxon were reported for the first time in Korea, which, along with the geopolitical characteristics of the survey area, proved that there is no domestic interest in seaweed-related diatoms. In particular, the appearance of species that have been reported in subtropical waters, such as the order Ardissoneales, requires continuous monitoring of marine seaweed-associated diatoms to confirm whether their colonization in Dokdo waters was due to climate change or species-specific water temperature tolerance. [ABSTRACT FROM AUTHOR]

Background In epiphytic bromeliads, the roots were previously considered to be poorly functional organs in the processes of absorption and metabolization of water and nutrients, while the leaves were considered to always act as protagonists in both functions. More recent discoveries have been changing this old view of the root system. Scope In this review, we address previous ideas regarding the function performed by the roots of epiphytic bromeliads (mere holdfast structures with low physiological activity) and the importance of a reduced or lack of a root system for the emergence of epiphytism. We present indirect and direct evidence that contradicts this older hypothesis. Furthermore, the importance of the root absorptive function mainly for juvenile tankless epiphytic bromeliads and the characteristics of the root absorption process of adult epiphytic tank bromeliads are discussed thoroughly from a physiological perspective. Finally, some factors (species, substrate, environmental conditions) that influence the absorptive capability of the roots of epiphytic tank bromeliads are also be considered, highlighting the importance that the absorptive role of the roots has for the plasticity of bromeliads that live on trees, which is an environment characterized by intermittent availability of water and nutrients. Conclusions The roots of tank-forming epiphytic bromeliads play important roles in the absorption and metabolization of nutrients and water. The importance of roots is greatest for juvenile tankless bromeliads since the root is the main absorptive organ. In larger plants with a tank, although the leaves become the protagonists in the resource acquisition process, the roots complement the absorptive function of the leaf trichomes, resulting in improved growth of these bromeliad. The physiological and biochemical properties of the processes of absorption and distribution of resources in the tissues appear to differ between absorption by trichomes and roots. [ABSTRACT FROM AUTHOR]

Leaf traits are known as indicative of species functional properties in angiosperms. Fern fronds are little studied in this concern, especially ex situ. We studied leaf mesophyll structure, pigments and gas exchange in four fern species grown in a glasshouse—Sphaeropteris cooperi (terrestrial tree fern), Phlebodium aureum (semi‐epiphytic herbaceous), Asplenium australasicum (epiphytic shrubby) and Platycerium bifurcatum (epiphytic herbaceous). Saturated assimilation rate (Asat) decreased and intrinsic water use efficiency (iWUE) increased from a terrestrial tree fern to epiphytic ferns. Asat positively correlated with chloroplast number (Nchl/A) and their surface area per leaf area (Achl/A). iWUE negatively related to Nchl/A and chlorophyll/carotenoid ratio. Most differences between species were found in the mesophyll thickness (MT) and mesophyll cell volume (Vcell) with the smallest values in S. cooperi and the largest ones in P. bifurcatum. We found that photosynthetic limitations in ferns were related to the chloroplast photosynthetic activity rather than to Nchl/A or pigment content which did not differ from most angiosperms. Epiphytic ferns showed larger values of Vcell per cell and per chloroplast compared to angiosperms and tree ferns. We concluded that an increase in MT and Vcell in the studied ferns was not associated with photosynthetic performance, but was related to volumetric cytoplasm–chloroplast ratio meaningful to light absorption and the water‐storage function of fern fronds. [ABSTRACT FROM AUTHOR]

Abstract Trans-Himalayan winters are projected to become milder, with shifting precipitation patterns and freeze-thaw cycles; changing stressors for their lichen communities. Lichens from Antarctica and high latitudes are cryoresistant when dry, but susceptible to cell damage if frozen when wet, or subjected to repeated freeze-thaw events. Little is known regarding cryoresistance in high-elevation, mid-latitude lichens. We collected thalli of nine species of epiphytic lichenized fungi, from three regions of the trans-Himalayas; at ≈ 4000 m, 3400 m and 2400 m elevation. We subjected thalli to differing freezing (continuous − 18 °C and − 36 °C or freeze-thaw cycles in natural daylight) and moisture conditions. Even dry thalli suffered some damage. Frozen wet thalli had greater chlorophyll degradation and reduced chlorophyll content. There were no clear elevational trends in freeze-thaw susceptibility: it caused more damage than continuous freezing. The most freeze-thaw resilient lichens were Dolichousnea longissima (from 4000 m) and Usnea florida (from 2400 m). However, species from coldest sites were most resilient to extreme freezing. Under predicted climate change conditions these sites would experience fewer annual freeze-thaw cycles, annual sub-zero days and frost days. Reduced freezing constraints might allow range expansion of mid-elevation lichens, but increase competitive pressures and temperature stressors impacting high-elevation lichens.

The fern independent gametophytes that can maintain populations by vegetative reproduction without conspecific sporophytes have been considered an unusual phenomenon found in some epiphytic or epilithic species of Hymenophyllaceae, Pteridaceae, Lomariopsidaceae, and Polypodiaceae. By chance, the discovery of mysterious strap-like gametophytes on Izu-Oshima Island, Japan, has led to the hypothesis that Hymenasplenium murakami-hatanakae, a fern species belonging to Aspleniaceae, can also form independent gametophytes. Our investigation revealed gametophyte populations of H. murakami-hatanakae on three islands in the Izu Islands. Based on chloroplast DNA analysis of the gametophyte and sporophyte populations, the gametophytes were found to be maintained by vegetative reproduction without a new supply of spores from sporophytes. A comparison of the surrounding vegetation at the collection sites showed that environmental factors such as light and humidity may influence the maintenance of gametophyte populations. These results clearly show that H. murakami-hatanakae is one of the ferns capable of forming independent gametophytes. This is the first report of independent gametophytes from the suborder Aspleniineae (eupolypod II). The discovery of the independent gametophyte within a phylogenetic lineage previously thought not to form independent gametophytes will provide important insights into the morphological and functional evolution of gametophytes in ferns. [ABSTRACT FROM AUTHOR]

The South America Dry Diagonal (SADD) is the most extensive and continuous portion of dry vegetation on the continent, characterised by lower rainfall and a marked dry season. Epiphytes are very poorly known and understudied in this area, even though they represent a high proportion of plant diversity in South America. Here, we compiled a dataset of epiphyte records from the SADD. The compiled epiphyte records date from 1859 to 2021, covering all four SADD domains, four countries, and 24 ecoregions. We utilised two databases for life form classification: Epilist and Brazil Flora Group. Our dataset contains 41,039 records distributed among 1119 epiphyte and hemiepiphyte species belonging to three main groups: angiosperms, ferns, and lycophytes. The SADD domains host a high number of unique species in each domain, with the Cerrado and Caatinga regions serving as primary hosts for the majority of species in the SADD dataset. Despite notable differences in species composition among domains, the least significant differences were observed between the Caatinga and Cerrado, as well as between the Chaco and the Pantanal. Orchidaceae, Bromeliaceae, and Polypodiaceae families exhibited the highest species diversity within the region. However, the species containing the highest number of specimens collected varied considerably among the domains. Herein, we also outlined some inconsistencies in the life-form classification across taxonomic bases, acknowledging the challenges of categorising epiphyte species while considering their intraspecific life-form variation. [ABSTRACT FROM AUTHOR]

Gracilaria chilensis (a.k.a. pelillo) is the most produced seaweed in Chile and Latin America, yet its cultivation has historically faced lots of pest-associated constrains that threat its profitability and sustainability. Pests show temporal cycles of recruitment, growth and death/senescence, variation normally linked with sharp changes in environmental factors occurring in estuarine areas whereby Gracilaria is cultivated. Here we report the appearance of a bladed Bangiales species epiphytic on long-line farmed Gracilaria and identified as Porphyra. This species recruits to cover up to 50–72% of G. chilensis early in a suspended set-up in spring, until a filamentous fungal-like organism colonizes Porphyra blades, infecting a wide proportion of its tissue. After this outbreak, Porphyra recruits collapse, disappearing in few weeks from farmed Gracilaria. Observations of diseased individuals, and subsequent isolation and marker-assisted taxonomy of the pathogen, provide evidence for the identification of this organism as Pythium porphyrae, the aetiological agent for the red rot disease in commercial nori/gim in Asia. This is the first reported case for P. porphyrae in Chile and the Southeastern Pacific as well as for a disease-driven natural biocontrol of a Gracilaria pest alga, suggesting an unknown -yet considerable- cryptic biodiversity acting as natural regulators of natural pests during a Gracilaria cultivation cycle. [ABSTRACT FROM AUTHOR]

Colaconema daviesii, a filamentous red alga, has been previously reported as an endophyte infesting Chondracanthus chamissoi. This study focuses on identifying the symptoms of C. daviesii infesting on haploid and diploid thalli of C. chamissoi. Co-cultivation of C. daviesii with diploid and haploid thalli of C. chamissoi was conducted under two treatments. Treatment 1 was under a 12:12 h (L:D) photoperiod for 40 days. Treatment 2 was under a 12:12 h (L:D) photoperiod for 20 days, followed by a 16:08 h (L:D) photoperiod for an additional 20 days. Parameters such as the density and coverage of C. daviesii filaments on C. chamissoi thalli were measured, as well as the growth rate and survival of C. chamissoi. Infestation occurred in both treatments and phases, with an increase in the presence of C. daviesii as the photoperiod extended. This relationship negatively affected the host in all measured parameters, with the diploid phase being more adversely affected. Infestation begins with spores under a 12:12 h (L:D) photoperiod condition, and filament development is observed on C. chamissoi thalli as the photoperiod increases. Early infestation symptoms were not evident, complicating the recognition of C. daviesii on haploid and diploid thalli of C chamissoi. The potential risk of transferring C. chamissoi contained filaments of C. daviesii through cultivation is postulated. [ABSTRACT FROM AUTHOR]

Abstract Background Citrus canker caused by the bacterium Xanthomonas citri (Hasse 1915) is known as a dangerous disease that has serious economic impacts on citrus production in many tropical and subtropical countries. In Iran, Citrus canker disease has caused significant damage to various citrus fruits, particularly limes. Nowadays, employing antagonistic bacteria as an effective and environmentally friendly method for plant disease management has gained special importance. Results Citrus leaf samples were collected from different regions of Iran, and after isolating epiphytic bacteria, ex planta and in planta investigations concerning antagonistic activities of the isolates against Xanthomonas citri pathotypes A and A* were performed. A total of 94 epiphytic bacterial isolates were isolated from citrus aerial parts. Based on biochemical, physiological, morphological, and genotypic tests, it was determined that these bacteria belong to the Bacillus and Staphylococcus genera. The highest inhibition activity against the pathogenic bacterium was related to isolates D4 and D5. Using the molecular method and the resulting dendrogram, it was found that these isolates were most similar to Bacillus amyloliquefaciens. The present findings demonstrated that pathogenicity test on key lime leaves infected with X. citri pathotypes A and A*, along with the application of the biocontrol strain B. amyloliquefaciens, resulted in a significant reduction in the number of canker lesions. Conclusion The results strongly suggested that the identified antagonistic bacterial isolates hold promising potential as biocontrol agents for managing citrus bacterial canker disease.

Prosthechea karwinskii is an orchid endemic to Mexico, threatened by the destruction of its habitat and the extraction of specimens to meet its demand for ornamental and religious use. Most of its populations, including the most locally abundant ones, are found in Oaxaca state. Variations in some floral traits have been observed in these populations. We implemented a morphometric analysis to assess their floral variation and identify the most significant characters in the morphological patterns of this orchid. Floral samples were collected from 17 populations of P. karwinskii in Oaxaca, as well as from specimens used as ornaments during Easter in an Oaxacan community (Zaachila), whose origin is unknown. Sampling of natural populations covered the environmental, geographic, and morphological variation of the species. We performed an analysis of variance (ANOVA), principal component analysis (PCA), canonical variate analysis (CVA), and cluster analysis, including 185 individuals and 45 variables (12 of them were discarded in the multivariate analyses due to high correlation). Characters of the column, lateral sepal, and labellum were most informative for the observed morphological patterns. Albarradas showed the greatest morphological differentiation, mainly due to the column. In general, individuals from the same locality tended to overlap more, especially the populations of Jaltianguis and Yahuiche, which were different from the geographically close population of Etla. Teposcolula presented the highest values in perianth characters, unlike Sola_Rancho Viejo. The specimens recovered from religious ornaments were morphologically more similar to those from Yanhuitlan and Etla. This morphometric analysis identified characters as potential taxonomic markers for P. karwinskii and related species, showing its potential to associate specimens of unknown origin with their probable geographical region. Our work encourages working on collaborative conservation strategies to ensure the long-term permanence of both the species and its traditional uses. [ABSTRACT FROM AUTHOR]

Epiphytic mosses are integral parts of forest community structure in the Darjeeling Hills of the Eastern Himalayan region with remarkable contributions to the ecosystem functionality. The study was framed to assess the richness and spatial distribution of epiphytic mosses growing on the basal trunk of Cryptomeria japonica (Thunb. ex. L.) D.Don, and also to evaluate the explanatory host traits for shaping the moss assemblage. Field measurements and sampling were performed near Lamahatta village within Darjeeling district on 270 microplots placed on tree trunks. A total of twelve mosses represented by the members of Dicranales and Hypnales were recorded. Low species diversity was observed with dominance and maximum cover of Syrrhopodon confertus. Canonical correspondence analysis predicted a distinct combination of chemical requirements for local colonization of each moss. The results also demonstrated influence of bark acidic inputs on abundance and co-existence of bryophytes. The outcome can be potentially helpful in depicting the community structure of non-vascular epiphytes, which may further be considered while developing forest management strategies. [ABSTRACT FROM AUTHOR]

Background and Aims There is growing interest in the functional ecology of poikilohydric non-vascular photoautotrophs (NVPs), including 'cryptogamic' bryophytes and lichens. These organisms are structurally important in many ecosystems, contributing substantially to ecosystem function and services, while also being sensitive to climate change. Previous research has quantified the climate change response of poikilohydric NVPs using predictive bioclimatic models with standard climate variables including precipitation totals and temperature averages. This study aimed for an improved functional understanding of their climate change response based on their growth rate sensitivity to moisture and light. Methods We conducted a 24-month experiment to monitor lichen hydration and growth. We accounted for two well-known features in the ecology of poikilohydric NVPs, and exemplified here for a structurally dominant lichen epiphyte, Lobaria pulmonaria : (1) sensitivity to multiple sources of atmospheric moisture including rain, condensed dew-formation and water vapour; and (2) growth determined by the amount of time hydrated in the light, driving photosynthesis, referred to as the I wet hypothesis. Key Results First, we found that even within an oceanic high-rainfall environment, lichen hydration was better explained by vapour pressure deficit than precipitation totals. Second, growth at a monthly resolution was positively related to the amount of time spent hydrated in the light, and negatively related to the amount of time spent hydrated in the dark. Conclusions Using multimodel averaging to project growth models for an ensemble of future climate change scenarios, we demonstrated reduced net growth for L. pulmonaria by the late 21st century, explained by extended climate dryness and lichen desiccation for periods when there is otherwise sufficient light to drive photosynthesis. The results further emphasize a key issue of photoperiodism when constructing functionally relevant models to understand the risk of climate change, especially for poikilohydric NVPs. [ABSTRACT FROM AUTHOR]

Background: Citrus canker caused by the bacterium Xanthomonas citri (Hasse 1915) is known as a dangerous disease that has serious economic impacts on citrus production in many tropical and subtropical countries. In Iran, Citrus canker disease has caused significant damage to various citrus fruits, particularly limes. Nowadays, employing antagonistic bacteria as an effective and environmentally friendly method for plant disease management has gained special importance. Results: Citrus leaf samples were collected from different regions of Iran, and after isolating epiphytic bacteria, ex planta and in planta investigations concerning antagonistic activities of the isolates against Xanthomonas citri pathotypes A and A* were performed. A total of 94 epiphytic bacterial isolates were isolated from citrus aerial parts. Based on biochemical, physiological, morphological, and genotypic tests, it was determined that these bacteria belong to the Bacillus and Staphylococcus genera. The highest inhibition activity against the pathogenic bacterium was related to isolates D4 and D5. Using the molecular method and the resulting dendrogram, it was found that these isolates were most similar to Bacillus amyloliquefaciens. The present findings demonstrated that pathogenicity test on key lime leaves infected with X. citri pathotypes A and A*, along with the application of the biocontrol strain B. amyloliquefaciens, resulted in a significant reduction in the number of canker lesions. Conclusion: The results strongly suggested that the identified antagonistic bacterial isolates hold promising potential as biocontrol agents for managing citrus bacterial canker disease. [ABSTRACT FROM AUTHOR]

Pyropia nereocystis is an annual northeastern Pacific‐bladed bangialean species whose macroscopic stage epiphytized the annual canopy forming bull kelp Nereocystis luetkeana. I examined three in situ facets of these epiphyte‐host dynamics in the central California region: (1) spatial and temporal variation in the presence of P. nereocystis epiphytes as a function of host density, (2) the relationship between individual host morphology and epiphytic P. nereocystis biomass, and (3) the ecophysiological growth ramifications for subtidal transplants of both life stages of P. nereocystis. Swath canopy surveys and whole host collections were conducted at five sites between November 2017 and February 2019. Additionally, transplants of P. nereocystis gametophytes and sporophytes were conducted across multiple subtidal depths. I observed temporal changes in the proportions of hosts epiphytized by P. nereocystis, with differences in seasonal persistence of P. nereocystis among sites and between years. Biomass of P. nereocystis was positively correlated with individual host stipe length, stipe surface area, and the primary principal component (PC) of stipe morphometrics denoted by principal component analysis (PCA). Gametogenesis in P. nereocystis epiphytes was spatially heterogeneous and limited for the 2018–2019 cohort due to comprehensive removal of hosts by the February 2019 sampling period. Transplants of P. nereocystis gametophytes yielded similar growth responses among depths, and sporophyte (conchocelis) transplant areal growth was positively correlated with transplant depth. These findings detail spatiotemporal complexity and multi‐scale (individual, site, and whole region) phenological nuances for central Californian P. nereocystis epiphytes. [ABSTRACT FROM AUTHOR]

Terrestrial organic matter subsidizes aquatic food webs and plays an important role in carbon cycling in lake ecosystems, where it is decomposed mainly by microbes. However, the contribution of terrestrial and aquatic microbiomes on terrestrial carbon cycling and their effects on the biochemical fate of carbon has remained understudied. Therefore, we explored the microbial carbon utilization of three chemically differing leaf species in lake water in microcosms and quantified the biochemical endpoints of leaf carbon in CO2, CH4, and microbial biomass. Additionally, we identified microbial taxa responsible for leaf carbon recycling and studied the role of epiphytic and endophytic leaf microbiomes in microbial community succession in lake water. Microbially utilized leaf carbon was mainly respired (82.7 ± 1.4%), whereas a small proportion (17.1 ± 1.4%) was assimilated into biomass. Carbon from nitrogen‐rich alder leaves was taken up at the fastest rate, whereas birch leaf addition produced the highest concentrations of CH4, suggesting that leaf chemistry affects the decomposition rate and biochemical fate of carbon. In particular, terrestrial bacteria shaped the succession of aquatic bacterial communities. The addition of leaves resulted in the equal contribution of epiphytic and endophytic bacteria in the lake water, whereas epiphytic fungi dominated the fungal community structure. Our results suggest that terrestrial bacteria originating from terrestrial leaves influence the microbiome succession in lake ecosystems and play a key role in linking terrestrial carbon to an aquatic food web and determining the quality of carbon emissions that are released into the atmosphere. [ABSTRACT FROM AUTHOR]

Tillandsia landbeckii Phil. is a rootless epiphyte that grows on dunes of the Atacama Desert. There is little information on its naturalhistory, particularly concerning its reproductive ability. To better understand whether sexual reproduction can contribute torecruitment in T. landbeckii, we examined its basic reproductive traits and developed a germination protocol. We marked andcensused plants, as well as collected seeds from four localities along an inland-coast gradient of the southernmost Tillandsia dunein Chile. Seeds were tested for viability and used for germination trials using four culture mediums. Plants vary in size, capsulesize and number of seeds per capsule along the gradient, with larger plants occurring inland. Both the probability of flowering andof producing capsules increased with plant size. However, seed viability was low and did not differ across localities. Germination trialswere successful, but also yielded relatively low germination probabilities. In summary, our results revealed plant size-relatedvariation in T. landbeckii’s reproductive capacity. In spite of this variation, however, low seed viability supports previous findingsthat sexual reproduction scarcely contributes to recruitment in this population; hence propagation of this species may eventually benecessary to promote genetic diversity.

Dokdo is an island located in the easternmost part of Korea, which has high levels of biodiversity of birds and fish, especially marine invertebrates. However, the biodiversity of microalgae, especially diatoms (Bacillariophyta), is relatively unknown, despite their ecological importance as primary producers of the marine food web and bioindicators of environmental conditions associated with climate change. To understand the biodiversity of seaweed-associated diatoms from Dokdo, we collected macroalgae present at a depth 5–15 m by SCUBA diving on 17 October 2017. There were a large number of diatoms (over 130 species), even though it was a one-time survey. As it includes too many taxa to cover at once, voucher flora for other taxonomic groups will be provided through the continuous serial papers. This is the first series of seaweed-associated diatoms, with 26 species belonging to the subphyla Melosirophytina and Coscinodisophytina, and the class Mediophyceae. Among these, seven species including one new taxon were reported for the first time in Korea, which, along with the geopolitical characteristics of the survey area, proved that there is no domestic interest in seaweed-related diatoms. In particular, the appearance of species that have been reported in subtropical waters, such as the order Ardissoneales, requires continuous monitoring of marine seaweed-associated diatoms to confirm whether their colonization in Dokdo waters was due to climate change or species-specific water temperature tolerance.

Hemiepiphytes have captured the attention of biologists since they seemingly hold clues to the evolution of epiphytes themselves. Hemiepiphytes are known to occur sporadically in the leptosporangiate ferns, but our understanding of their evolution remains limited by the relatively small number of detailed observations. This study adds to our knowledge by documenting seven species previously assumed to be holoepiphytes. This finding was based on fieldwork conducted in the Baining Mountains of Papua New Guinea that resulted in 319 collections representing 206 species. Approximately 3% of these species were hemiepiphytes: Asplenium acrobryum, A. amboinense, A. scandens, A. scolpendropsis, Crepidomanes aphlebioides, Leptochilus macrophyllus, and Sphaerostephanos scandens. All started growth as low-trunk epiphytes, and later, as larger climbing plants, exhibited strongly dimorphic roots consisting of short clasping ones that affixed the rhizome to the trunks and long feeding roots that entered the soil. Most of the seven hemiepiphyte species that we found exhibited distichous phyllotaxy and dorsiventrally flattened rhizomes, suggesting morphological convergence associated with this habit in four families. These new records suggest that large hemiepiphytic clades occur in Asplenium and Leptochilus. Our observations expand the geographic and taxonomic breadth of hemiepiphytic ferns, provide a baseline estimate of their diversity within a tropical flora, and offer morphological and phylogenetic clues to uncover additional records. [ABSTRACT FROM AUTHOR]

Epiphytic species are ecologically important and a significant component of biodiversity. To ensure their efficient conservation, we need to understand their ecology and host plant associations. It is also important to investigate how the predicted temperature change will affect their future distribution. Here, we use data collected in Nepal to investigate how epiphytic orchids are associated with host species, their distribution patterns, and how they may be threatened by the predicted increase in temperature towards the end of the 21st century. We used the phi coefficient (Φ) of association to calculate the associations of epiphytic orchid species with plants and rarefaction to describe the diversity of orchids associated with a particular host species. We used interpolation to estimate the distribution of epiphytic orchids and their host species along altitudinal gradients. The phi (Φ) coefficient of association revealed that 30 species of host plants showed more association with different orchid species than expected. The number of epiphytic orchids increased with the number of host individuals. We predict that an increase in temperature by ~3 °C, which is a more moderate value of temperature increase by the end of the 21st century, will affect at least 52 narrow-ranged species of orchids and 58 narrow-ranged species of host plants. Therefore, we should make efforts to prevent many plant species from becoming extinct, as an increase in temperature is likely to affect their existence. [ABSTRACT FROM AUTHOR]

Understanding the colonization process of species living in a dynamic fragmented habitat is essential to assess their persistence. In the metapopulation theory, the colonization of a species can be quantified using the turnover of occupancy in habitat patches. However, this approach is often limited by the feasible size of surveyed areas. Because many species are capable of long‐distance dispersal, such areas often constitute open systems undergoing colonization of propagules coming from outside, the 'background deposition'. We focus on disentangling background deposition from local colonization among surveyed patches when analyzing turnover. We consider two spatial scales: 1) focal areas where all patches are monitored over time; 2) a larger extent, encompassing the focal areas, over which the distribution of the target species is quantified with a coarse spatial grain. Our key idea is to use the regional connectivity of focal areas within the larger scale as a covariate when analyzing colonization events within focal areas. A positive effect of regional connectivity on the colonization probability of patches may indicate background deposition. We applied this approach to the epiphytic bryophyte Dicranum viride in a managed temperate deciduous forest, considering phorophyte trees as patches, forest stands as focal areas and the whole forest as the larger scale. We combined a fine‐grained turnover survey of occupied trees within three forest stands (~ 3 ha) with a coarse‐grained snapshot of D. viride distribution over the forest (~ 15 000 ha). Regional connectivity came out as the most significant factor, with a strong positive effect on colonization probability within stands. However, it was attributed to sources in the immediate vicinity of focal stands, suggesting a short‐ranged colonization process occurring across stands' borders rather than long‐distance background deposition. Our results thus call for maintaining a stepping‐stone of habitat across the forest through time to improve D. viride persistence. [ABSTRACT FROM AUTHOR]

Microbial symbionts of plants constitute promising sources of biocontrol organisms to fight plant pathogens. Bacillus sp. G2112 and Pseudomonas sp. G124 isolated from cucumber (Cucumis sativus) leaves inhibited the plant pathogens Erwinia and Fusarium. When Bacillus sp. G2112 and Pseudomonas sp. G124 were co-cultivated, a red halo appeared around Bacillus sp. G2112 colonies. Metabolite profiling using liquid chromatography coupled to UV and mass spectrometry revealed that the antibiotic phenazine-1-carboxylic acid (PCA) released by Pseudomonas sp. G124 was transformed by Bacillus sp. G2112 to red pigments. In the presence of PCA (>40 µg/mL), Bacillus sp. G2112 could not grow. However, already-grown Bacillus sp. G2112 (OD600 > 1.0) survived PCA treatment, converting it to red pigments. These pigments were purified by reverse-phase chromatography, and identified by high-resolution mass spectrometry, NMR, and chemical degradation as unprecedented 5N-glucosylated phenazine derivatives: 7-imino-5N-(1′β-D-glucopyranosyl)-5,7-dihydrophenazine-1-carboxylic acid and 3-imino-5N-(1′β-D-glucopyranosyl)-3,5-dihydrophenazine-1-carboxylic acid. 3-imino-5N-(1′β-D-glucopyranosyl)-3,5-dihydrophenazine-1-carboxylic acid did not inhibit Bacillus sp. G2112, proving that the observed modification constitutes a resistance mechanism. The coexistence of microorganisms—especially under natural/field conditions—calls for such adaptations, such as PCA inactivation, but these can weaken the potential of the producing organism against pathogens and should be considered during the development of biocontrol strategies. [ABSTRACT FROM AUTHOR]

Vriesea is one of the most diverse genera in the Brazilian Atlantic Forest, comprising approximately 170 species in this domain. Included in this genus, the V. ensiformis group encompasses ten species that are distributed from northeastern to southern Brazil. During field expeditions in Parque Nacional da Serra dos Órgãos, Rio de Janeiro, Brazil, we found a new species which was previously long recognized as Vriesea aff. gradata in herbaria. Thus, here we aim to describe V. organensis and investigate its phylogenetic relationship to other species in the V. ensiformis group through a total evidence approach. We conducted an extensive literature review, herbarium consulting and field trips to gather data for describing the new species. Additionally, we constructed a concatenated matrix of molecular and morphological data to generate a phylogenetic hypothesis for the V. ensiformis group. Vriesea organensis is morphologically related to V. psittacina, V. gradata and V. fluviatilis and is described as possibly critically endangered. Our phylogenetic tree revealed that V. organensis is closely related to V. fluviatilis, in contrast to the herbarium hypothesis of similarity with V. gradata. The new species is characterized by the floral bracts incurvate and strongly carinate at the apex, rachis exposed when flowering, petal yellow with green apex and stigma exceeding the anthers. Furthermore, our findings indicate that the V. ensiformis group is not monophyletic based on our dataset. [ABSTRACT FROM AUTHOR]

Abstract Terrestrial organic matter subsidizes aquatic food webs and plays an important role in carbon cycling in lake ecosystems, where it is decomposed mainly by microbes. However, the contribution of terrestrial and aquatic microbiomes on terrestrial carbon cycling and their effects on the biochemical fate of carbon has remained understudied. Therefore, we explored the microbial carbon utilization of three chemically differing leaf species in lake water in microcosms and quantified the biochemical endpoints of leaf carbon in CO2, CH4, and microbial biomass. Additionally, we identified microbial taxa responsible for leaf carbon recycling and studied the role of epiphytic and endophytic leaf microbiomes in microbial community succession in lake water. Microbially utilized leaf carbon was mainly respired (82.7 ± 1.4%), whereas a small proportion (17.1 ± 1.4%) was assimilated into biomass. Carbon from nitrogen‐rich alder leaves was taken up at the fastest rate, whereas birch leaf addition produced the highest concentrations of CH4, suggesting that leaf chemistry affects the decomposition rate and biochemical fate of carbon. In particular, terrestrial bacteria shaped the succession of aquatic bacterial communities. The addition of leaves resulted in the equal contribution of epiphytic and endophytic bacteria in the lake water, whereas epiphytic fungi dominated the fungal community structure. Our results suggest that terrestrial bacteria originating from terrestrial leaves influence the microbiome succession in lake ecosystems and play a key role in linking terrestrial carbon to an aquatic food web and determining the quality of carbon emissions that are released into the atmosphere.

Citizen science has successfully contributed lichen records to air pollution assessments and for detecting biodiversity hotspots, while its potential to survey broad lichen distributions and trends in natural ecosystems is less clear. The main issue is whether non-professional observers would be willing to visit remote areas to record inconspicuous organisms. We launched a nationwide citizen science campaign "Ready! Set! Lichen!" in Estonia (Northern Europe) that focused on collecting digital photo-based data on lichen distributions comparatively on live trees in forests versus in cut-over sites. Altogether 1101 trees were surveyed by 362 participants. Of all observations, 86% were acceptable and revealed 86 species plus 33 morphospecies as identified by experts. For a test set of selected 12 common epiphytic species, the campaign expanded their known national distributions on average 13%, independently of their conspicuousness (thallus type). Our results indicated that a mass participation approach of citizen science: (i) can provide significant data to monitoring broad-scale population trends of common forest lichens, but the contributions remained small regarding (ii) the knowledge on rare and sparsely distributed habitat specialists and (iii) ecological factors behind the distributions (due to difficulties in keeping valid sampling design). We conclude that citizen-science projects on inconspicuous highly diverse taxon groups can contribute to conservation research if these projects are specifically designed for feasible goals, and we outline six main areas of application for lichen studies. [ABSTRACT FROM AUTHOR]

Summary: Epiphytes and their associated biota are increasingly recognized as contributing to biodiversity and to filling critical ecosystem functions in world forests. However, the attributes that have made them successful in canopy environments also make them vulnerable to natural and human‐induced disturbances. Drawing upon ecological frameworks to understand disturbance, I categorized and synthesized the drivers and the consequences of disturbances on epiphytic materials. Across all impacts, disturbance agents were significantly more likely to lead to negative, rather than positive, effects in both tropical and temperate locales. Significantly more studies reported negative effects on abundance, diversity, community composition and connectivity, but some studies showed that disturbances enhanced these attributes. Although particular disturbance agents did not differently influence individual consequences, they explained a significant portion of variation in aggregated totals. Surprisingly, relative to human disturbances, natural disturbances were more likely to lead to negative effects. Many studies provided recommendations for effective societal responses to mitigate negative impacts, such as retaining large, old trees in forestry operations, patch‐clearing for epiphyte harvest, maximizing forest fragment size, using epiphytes as bioindicators of disturbance, and applying principles of community forestry to land management. Future actions should also include communication of these results to policymakers and land managers. [ABSTRACT FROM AUTHOR]

Vanda falcata is an epiphytic orchid native to East Asia with high horticultural and ornamental value. However, its wild populations are at risk of extinction due to overcollection and habitat loss. Orchids are highly dependent on mycorrhizal fungi for their nutrient acquisition from seed germination to adulthood; therefore, understanding their mycorrhizal associations throughout the life cycle is essential for their conservation. We investigated the mycorrhizal fungi of adult V. falcata plants through the molecular identification of root samples from 40 individual plants from 13 sites, covering a distance of 1200 km across Japan. To identify the fungi that promote V. falcata seed germination, we performed seed germination tests in vitro with fungal isolates from V. falcata and other epiphytic orchids. In adult plants, we detected a total of 11 operational taxonomic units (OTUs) within two fungal families, Ceratobasidiaceae and Tulasnellaceae, and a single Tulasnellaceae OTU (TU11) was found in samples from 12 sites. However, Vanda falcata seed germination and early development were induced in vitro by Ceratobasidiaceae fungi rather than Tulasnellaceae fungi, including TU11. These results suggest that different mycorrhizal fungi may be predominantly associated with V. falcata in the adult and seed germination stages. This mycorrhizal switching suggests that effective mycorrhizal fungi for conservation may differ between the adult and juvenile stages, even within a single orchid species. Our findings clarify the mycorrhizal associations of endangered epiphytic orchid species and could improve conservation efforts for these rare plants. [ABSTRACT FROM AUTHOR]

The biodiversity hotspot of central Chile is home to a high proportion of endemic species, but some of these species are inconspicuous and not easily observed. During a botanical exploration in the Los Queules National Reserve (Chile), a population of Asplenium trilobum Cav. was identified. The plants were found growing on the bark of a Myrceugenia parvifolia (DC.) Kausel tree in a small swamp next to specimens of Drimys winteri J.R.Forst. & G.Forst. (35°59'11.84"S; 72°41'11.53"W). Several previously unrecorded species were found, including Carex cf. excelsa Poepp. ex Kunth, Chusquea cf. quila Kunth, Ercilla cf. spicata (Bertero) Moq., and Boquila trifoliolata (DC.) Decne., highlighting the importance of exploring and documenting this biodiversity hotspot. The discovery in this wilderness area extends the distribution 86 km north on the continent, which was previously limited to the east of the municipality of Penco in the Biobío region (36°44'9.26"S; 72°57'42.5"W). This paper presents an observed specimen, its locality, and associated species.

The genus Amphidinium Clap. & J. Lachm. comprises a high diversity of planktonic and benthic (epiphytic and sand-dwelling) dinoflagellates from marine and freshwater ecosystems. High morphological plasticity and vaguely defined genus characteristics (e.g., a small epicone size) have complicated the clear delineation of species boundaries. Although six Amphidinium morphospecies have been reported from Mexican coastal waters, species identifications are uncertain and not generally supported by molecular phylogenetic data. In this study, seven isolates of Amphidinium from diverse benthic coastal locations on the NE Pacific, Gulf of California, and southern Gulf of Mexico were subjected to critical morphological analysis using photonic and scanning electron microscopy. The phylogenetic reconstruction was based on nuclear-encoded, partial large-subunit (LSU) rDNA and internal transcribed spacer I and II (ITS1 and ITS2) sequences. The revised phylogenetic analysis was consistent with the traditional subdivision of the genus Amphidinium into two sister groups: Herdmanii and Operculatum clades. This study provided the first confirmed records of A. theodorei and A. massartii from coastal waters of Mexico. The molecular phylogenetic evidence indicated that the morphologically described A. cf. carterae from Baja California was in fact more closely allied with A. eilatiensis sequences. A few Amphidinium species are known to form toxigenic (i.e., fish-killing) harmful algal blooms worldwide, and therefore knowledge on species diversity and biogeography is critical in developing effective strategies for evaluating the potential emerging threat in Mexican coastal waters.

Prosthechea karwinskii is an orchid endemic to Mexico, threatened by the destruction of its habitat and the extraction of specimens to meet its demand for ornamental and religious use. Most of its populations, including the most locally abundant ones, are found in Oaxaca state. Variations in some floral traits have been observed in these populations. We implemented a morphometric analysis to assess their floral variation and identify the most significant characters in the morphological patterns of this orchid. Floral samples were collected from 17 populations of P. karwinskii in Oaxaca, as well as from specimens used as ornaments during Easter in an Oaxacan community (Zaachila), whose origin is unknown. Sampling of natural populations covered the environmental, geographic, and morphological variation of the species. We performed an analysis of variance (ANOVA), principal component analysis (PCA), canonical variate analysis (CVA), and cluster analysis, including 185 individuals and 45 variables (12 of them were discarded in the multivariate analyses due to high correlation). Characters of the column, lateral sepal, and labellum were most informative for the observed morphological patterns. Albarradas showed the greatest morphological differentiation, mainly due to the column. In general, individuals from the same locality tended to overlap more, especially the populations of Jaltianguis and Yahuiche, which were different from the geographically close population of Etla. Teposcolula presented the highest values in perianth characters, unlike Sola_Rancho Viejo. The specimens recovered from religious ornaments were morphologically more similar to those from Yanhuitlan and Etla. This morphometric analysis identified characters as potential taxonomic markers for P. karwinskii and related species, showing its potential to associate specimens of unknown origin with their probable geographical region. Our work encourages working on collaborative conservation strategies to ensure the long-term permanence of both the species and its traditional uses.

ABSTRACT This study presents a new orchid species of the genus Catasetum belonging to the group of species with symmetrical and parallel antennae. It was found in terra-firme and floodplain forests in the Brazilian states of Amazonas and Pará. We provide a formal description of the new species, images, and notes on distribution, habitat, phenology, flower visitors and preliminary conservation status. We compare it with C. cristatum and C. barbatum, both sympatric and morphologically most similar to the new species. It was preliminarily classified in the Endangered (EN) category according to IUCN criteria based on the extent of occurrence, area of occupation, number of occurrence locations and the risks that the known populations are exposed to (deforestation and predatory collection).

Epiphytic lichens and bryophytes provide important habitat for microarthropods, yet little work has documented epiphytic microarthropod assemblages. Further, the response of epiphytes and their associated microarthropod communities to varying levels of forest disturbance and cutting intensity are not well known. We conducted a case study to provide an initial community description of epiphyte-dwelling microarthropods in Adirondack northern hardwoods, and to assess potential for impacts of aggregated and dispersed patterns of reserve tree retention to these communities. In total, 79 families of microarthropods were identified in the 0.14 m2 of samples. Late summer average daily maximum temperatures were 3.2 °C higher in the shelterwood, and three years following treatments the per-unit area dry weight of the bole-associated bryophyte Neckera pennata was 34 % lower in the shelterwood. Microarthropod richness and density were distinctly greater in epiphyte substrates at the base of trees, and were reduced in the shelterwood. Several indicator taxa were identified within the basal bryophytes in the reserve treatment, and in both bryophytes the microarthropod assemblages were more homogenous in the shelterwood. A few mobile and heavily sclerotized taxa persisted in shelterwood substrates, especially in the lichens which lacked 3-dimensional structure. This case study revealed a diverse community of microarthropods in northern hardwood forests that were structured by epiphyte type, height on tree and, potentially, by canopy removal, and suggests conservation value of aggregated tree retention when applying even-age regeneration methods with respect to epiphytic bryophytes, lichens, and their associated invertebrates.

Brown algae (Phaeophyceae) are habitat‐forming species in coastal ecosystems and include kelp forests and seaweed beds that support a wide diversity of marine life. Host‐associated microbial communities are an integral part of phaeophyte biology, and whereas the bacterial microbial partners have received considerable attention, the microbial eukaryotes associated with brown algae have hardly been studied. Here, we used broadly targeted "pan‐eukaryotic" primers (metabarcoding) to investigate brown algal‐associated eukaryotes (the eukaryome). Using this approach, we aimed to investigate the eukaryome of seven large brown algae that are important and common species in coastal ecosystems. We also aimed to assess whether these macroalgae harbor novel eukaryotic diversity and to ascribe putative functional roles to the host‐associated eukaryome based on taxonomic affiliation and phylogenetic placement. We detected a significant diversity of microeukaryotic and algal lineages associated with the brown algal species investigated. The operational taxonomic units (OTUs) were taxonomically assigned to 10 of the eukaryotic major supergroups, including taxonomic groups known to be associated with seaweeds as epibionts, endobionts, parasites, and commensals. Additionally, we revealed previously unrecorded sequence types, including novel phaeophyte OTUs, particularly in the Fucus spp. samples, that may represent fucoid genomic variants, sequencing artifacts, or undescribed epi‐/endophytes. Our results provide baseline data and technical insights that will be useful for more comprehensive seaweed eukaryome studies investigating the evidently lineage‐rich and functionally diverse symbionts of brown algae. [ABSTRACT FROM AUTHOR]

Summary: Dischidia thongphaphumensis is a newly discovered species from Thong Pha Phum National Park, Kanchanaburi province, western Thailand. It is here described, illustrated and compared with its morphologically most similar species, D. rimicola. These two species are similar in sessile inflorescences, creamy white flowers without corolline coronas, lanceolate-triangular corolla lobes with antrorse trichomes and longitudinal ribs on the inner surface, and sagittate staminal corona lobes. However, the new species can be distinguished from D. rimicola by its ovate-lanceolate or lanceolate leaves with papillose adaxial epidermal cells, and by its staminal corona lobes that are characterised by narrowly falcate lateral arms. [ABSTRACT FROM AUTHOR]

Hymenophyllaceae (filmy ferns), with ca. 430 species, are the most species-rich family of early diverging leptosporangiate ferns but have a poor fossil record dating back to the Late Triassic period. Traditionally, Hymenophyllaceae comprise two species-rich genera or clades: Hymenophyllum (hymenophylloids) and Trichomanes sensu lato (s.l.) (trichomanoids). Unequivocal fossils of Hymenophyllum have been reported from the Early Cretaceous of central Mongolia and the early Eocene of Okanogan Highlands, Washington, USA. However, despite being a highly diversified lineage with an estimated 184 extant species, Trichomanes s.l. lack a definitive fossil record, which severely affects the reliability of the molecular dating of this group. Here, we report the first unequivocal fossil record of Trichomanes s.l. as T. angustum comb. nov. on the basis of fertile material with tubular involucres and long exserted receptacles from the mid-Cretaceous Kachin amber, Myanmar. This species was previously tentatively assigned to Hymenophyllites due to a lack of fertile evidence. Inferred to be an epiphytic fern, T. angustum further enriches the species diversity of the epiphytic palaeocommunities in the mid-Cretaceous Kachin amber, which are mainly composed of Porellalean leafy liverworts and Dicranalean and Hypnodendralean mosses. Fossil records indicate that Hymenophyllaceae probably originated in the tropical Pangea at the latest in the Triassic when all continents were coalesced into a single landmass and had already accumulated some notable diversity in low-middle latitude areas of Laurasia by the mid-Cretaceous period. [ABSTRACT FROM AUTHOR]

The fern family Polypodiaceae, with over 1600 species, is not only one of the most species‐rich families of ferns, but also a major contributor to the vascular epiphytic diversity throughout the tropics. Although the vast majority of species belonging to this family prefer to grow as epiphytes, several species colonize successfully rheophytic, lithophytic, and even terrestrial habitats. Here, we explore the hypothesis that non‐epiphytic habitat preferences, including terrestrial growth, evolved secondarily with epiphytes being the plesiomorphic habitat preference. The results of phylogenetic analyses, based on dense taxon sampling and four chloroplast DNA regions, were integrated with divergence time estimates and ancestral character state reconstructions to test these predictions. Both fossils and secondary calibration data were incorporated to obtain divergence time estimations. The results support the prediction of multiple transitions from epiphytic/lithophytic to terrestrial/rheophytic habitats occurring mainly in the Microsoreae lineage. The change in niche preferences coincides with niche colonization opportunities created by climatic fluctuations and geographical changes during the Oligocene and Miocene periods. [ABSTRACT FROM AUTHOR]

The Cyclanthaceae comprise a relatively small family of about 230 species and 12 genera in the Pandanales that is widespread in wet Neotropical forests. The great majority of species can be divided into three growth forms (understory herbs, epiphytes, and root-climbing hemiepiphytes) that share functional traits with similar growth forms present in the Araceae, a member of the Alismatales and not closely related. Our objectives were first to characterize the diversity, functional growth forms, and ecological traits of Cyclanthaceae at the La Selva Biological Station. Specific functional leaf and canopy traits of terrestrial herbs and epiphytes are very similar and associated with ecological success in both families. We further examined the functional traits of root-climbing hemiepiphytes, a specialized growth form that links the two families but rare in other families and argue that their specialized functional traits allow them to be considered as a distinct functional growth form. A key trait in distinguishing hemiepiphytes which are rare outside of the Cyclanthaceae and Araceae is the severance of the main stem hydraulic connection to the soil early in plant development. We used field data to examine the possible evolutionary pathways of developmental and ecological transition from terrestrial to hemiepiphyte growth forms. The broader ecological success of hemiepiphytic Araceae compared to Cyclanthaceae is hypothesized to result from the presence of heteroblasty in developing stems and leaves which allows more efficient utilization of complex canopy light environments of wet tropical forests. [ABSTRACT FROM AUTHOR]

The biodiversity hotspot of central Chile is home to a high proportion of endemic species, but some of these species are inconspicuous and not easily observed. During a botanical exploration in the Los Queules National Reserve (Chile), a population of Asplenium trilobum Cav. was identified. The plants were found growing on the bark of a Myrceugenia parvifolia (DC.) Kausel tree in a small swamp next to specimens of Drimys winteri J.R.Forst. & G.Forst. (35°59'11.84"S; 72°41'11.53"W). Several previously unrecorded species were found, including Carex cf. excelsa Poepp. ex Kunth, Chusquea cf. quila Kunth, Ercilla cf. spicata (Bertero) Moq., and Boquila trifoliolata (DC.) Decne., highlighting the importance of exploring and documenting this biodiversity hotspot. The discovery in this wilderness area extends the distribution 86 km north on the continent, which was previously limited to the east of the municipality of Penco in the Biobío region (36°44'9.26"S; 72°57'42.5"W). This paper presents an observed specimen, its locality, and associated species. [ABSTRACT FROM AUTHOR]

The genus Amphidinium Clap. & J. Lachm. comprises a high diversity of planktonic and benthic (epiphytic and sand-dwelling) dinoflagellates from marine and freshwater ecosystems. High morphological plasticity and vaguely defined genus characteristics (e.g., a small epicone size) have complicated the clear delineation of species boundaries. Although six Amphidinium morphospecies have been reported from Mexican coastal waters, species identifications are uncertain and not generally supported by molecular phylogenetic data. In this study, seven isolates of Amphidinium from diverse benthic coastal locations on the NE Pacific, Gulf of California, and southern Gulf of Mexico were subjected to critical morphological analysis using photonic and scanning electron microscopy. The phylogenetic reconstruction was based on nuclear-encoded, partial large-subunit (LSU) rDNA and internal transcribed spacer I and II (ITS1 and ITS2) sequences. The revised phylogenetic analysis was consistent with the traditional subdivision of the genus Amphidinium into two sister groups: Herdmanii and Operculatum clades. This study provided the first confirmed records of A. theodorei and A. massartii from coastal waters of Mexico. The molecular phylogenetic evidence indicated that the morphologically described A. cf. carterae from Baja California was in fact more closely allied with A. eilatiensis sequences. A few Amphidinium species are known to form toxigenic (i.e., fish-killing) harmful algal blooms worldwide, and therefore knowledge on species diversity and biogeography is critical in developing effective strategies for evaluating the potential emerging threat in Mexican coastal waters. [ABSTRACT FROM AUTHOR]

Microcoelia and the monospecific Taeniorrhiza and Chauliodon are notable among Afrotropical angraecoid orchids for being leafless. However, the affinity among these genera was not addressed in previous molecular phylogenetic studies, thus precluding the understanding of how many times has leaflessness evolved in angraecoids. The discovery of an additional species ascribable to Taeniorrhiza in Gabon, and a revision of all material referrable to this genus in herbarium collections, created the possibility to investigate the phylogenetic position of Taeniorrhiza relative to Microcoelia and Chauliodon. Based on phylogenetic inference using ITS‐1 and two plastid regions (matK/trnK, trnL‐trnF), and including 20 of the 34 species of Microcoelia recognised prior to our study, we here demonstrate that Taeniorrhiza and Chauliodon are deeply imbedded in Microcoelia, and are thus treated here as synonyms of the last. Accordingly, we describe the novelty from Gabon as a new species of Microcoelia: Microcoelia nguemae sp. nov. The new species is illustrated with colour photographs, and also with line drawings. Its preliminarily IUCN conservation status is provided. The novelty is notable for the dorsiventrally asymmetric distribution of pneumathodes along its roots and for bearing the longest lip spur in this Afro‐Malagasy epiphytic genus. The new phylogenetic framework suggests a single origin of leaflessness in Afrotropical angrecoids and reveals the informative value of the rostellum to reconstruct relationships within Microcoelia. This serves as the basis of a newly proposed sectional treatment for Microcoelia, recognising 37 species, one new section, a new status for the defunct genus Encheiridion and the redefinition of Microcoelia sect. Microcoelia and sect. Brachyglossa. [ABSTRACT FROM AUTHOR]

Large numbers of bacteria live on the surface of various brown algae and can produce alginate lyases to consume alginate, an important component of the cell wall of brown algae. Sargassum is a genus of the largest canopy-forming brown algae of more than 150 species, which are widely distributed in tropical and subtropical environments. However, our knowledge about the epiphytic bacteria and the alginate lyase-excreting bacteria from Sargassum is still primitive. Here, we investigated the diversity of the culturable epiphytic bacteria and alginate-degrading bacteria from Sargassum samples collected from the coastal seawaters of Shandong Province, China. In total, 37 strains belonging to 21 genera in 3 phyla were isolated, including 15 previously unreported genera, of which Vibrio (6/37) and Pseudoalteromonas (5/37) are the dominant genera. Eight strains, mainly Vibrio and Pseudoalteromonas species, were further identified as alginate lyase-excreting strains that can utilize alginate for growth. The extracellular alginolytic activity of the 8 strains was determined, and strains Vibrio sp. C42 and Pseudoalteromonas sp. M9 showed the highest activity. These results provide a better understanding of brown algae epiphytes and alginate-degrading bacteria, and are fundamental for further studies on the interactions between brown algae and their epiphytes. [ABSTRACT FROM AUTHOR]

Plant microbiomes are known to influence host fitness and ecosystem functioning, but mechanisms regulating their structure are poorly understood.Here, we explored the assembly mechanisms of leaf epiphytic and endophytic bacterial communities using a subtropical forest biodiversity experiment.Both epiphytic and endophytic bacterial diversity increased as host tree diversity increased. However, the increased epiphytic diversity in more diverse forests was driven by greater epiphytic diversity (i.e. greater α‐diversity) on individual trees, whereas the increased endophytic diversity in more diverse forests was driven by greater dissimilarity in endophytic composition (i.e. greater β‐diversity) among trees. Mechanistically, responses of epiphytes to changes in host diversity were consistent with mass effects, whereas responses of endophytes were consistent with species sorting.Synthesis. These results provided novel experimental evidence that biodiversity declines of plant species will lead to biodiversity declines of plant‐associated microbiomes, but the underlying mechanism may differ between habitats on the plant host. [ABSTRACT FROM AUTHOR]