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1.
Environmental sampling yielded two yeast species belonging to Microstromatales (Exobasidiomycetes, Ustilaginomycotina). The first species was collected from a leaf phylloplane infected by the rust fungus Coleosporium plumeriae, and represents a new species in the genus Jaminaea, for which the name Jaminaea rosea sp. nov. is proposed. The second species was isolated from air on 50% glucose media and is most similar to Microstroma phylloplanum. However, our phylogenetic analyses reveal that species currently placed in Microstroma are not monophyletic, and M. phylloplanum, M. juglandis and M. albiziae are not related to the type species of this genus, M. album. Thus, Pseudomicrostroma gen. nov. is proposed to accommodate the following species: P. glucosiphilum sp. nov., P. phylloplanum comb. nov. and P. juglandis comb. nov. We also propose Parajaminaea gen. nov. to accommodate P. albizii comb. nov. and P. phylloscopi sp. nov. based on phylogenetic analyses that show these are not congeneric with Jaminaea or Microstroma. In addition, we validate the genus Jaminaea, its respective species and two species of Sympodiomycopsis and provide a new combination, Microstroma bacarum comb. nov., for the anamorphic yeast Rhodotorula bacarum. Our results illustrate non-monophyly of Quambalariaceae and Microstromataceae as currently circumscribed. Taxonomy of Microstroma and the Microstromataceae is reviewed and discussed. Finally, analyses of all available small subunit rDNA sequences for Jaminaea species show that J. angkorensis is the only known species that possess a group I intron in this locus, once considered a potential feature indicating the basal placement of this genus in Microstromatales.  相似文献   

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Increasing temperature and drought intensity is inducing the phenomenon of the so-called “hotter drought”, which is expected to increase in frequency over the coming decades across many areas of the globe, and is expected to have major implications for forest systems. Consequences of hotter drought could be especially relevant for closely related species overlapping their distributions, since differences in response can translate into range shifts. We assessed the effect of future climatic conditions on the performance of five ecologically distinct pine species common in Europe: Pinus halepensis, P. pinaster, P. nigra, P. sylvestris and P. uncinata. We hypothesised that Mediterranean species inhabiting dry, low-elevation sites will be less affected by the expected warming and drought increase than species inhabiting cold-wet sites. We performed a controlled conditions experiment simulating current and projected temperature and precipitation, and analysed seedling responses in terms of survival, growth, biomass allocation, maximum photochemical efficiency (F v/F m) and plant water potential (Ψ). Either an increase in temperature or a reduction in water input alone reduced seedling performance, but the highest impact occurred when these two factors acted in combination. Warming and water limitation reduced Ψ, whereas warming alone reduced biomass allocation to roots and F v/F m. However, species responded differentially to warmer and drier conditions, with lowland Mediterranean pines (P. halepensis and P. pinaster) showing higher survival and performance than mountain species. Interspecific differences in response to warmer, drier conditions could contribute to changes in the relative dominance of these pine species in Mediterranean regions where they co-occur and a hotter, drier climate is anticipated.  相似文献   

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During a study comparing the ectomycorrhizal root communities in a native forest with those at the Arnold Arboretum in Massachusetts (USA), the European species Tuber borchii was detected on the roots of a native red oak in the arboretum over two successive years. Since T. borchii is an economically important edible truffle native to Europe, we conducted a search of other roots in the arboretum to determine the extent of colonization. We also wanted to determine whether other non-native Tuber species had been inadvertently introduced into this 140-year-old Arboretum because many trees were imported into the site with intact soil and roots prior to the 1921 USDA ban on these horticultural practices in the USA. While T. borchii was not found on other trees, seven other native and exotic Tuber species were detected. Among the North American Tuber species detected from ectomycorrhizae, we also collected ascomata of a previously unknown species described here as Tuber arnoldianum. This new species was found colonizing both native and non-native tree roots. Other ectomycorrhizal taxa that were detected included basidiomycetes in the genera Amanita, Russula, Tomentella, and ascomycetes belonging to Pachyphlodes, Helvella, Genea, and Trichophaea. We clarify the phylogenetic relationships of each of the Tuber species detected in this study, and we discuss their distribution on both native and non-native host trees.  相似文献   

6.
In connection with the problems of identification of certain species of the genus Ponticola, and especially their juveniles, morphological and genetic studies of gobies collected in the northwestern part of the Black Sea basin were carried out using literature data and museum collections. Karyological data indicate a distinct species status of western (P. odessicus) and eastern (P. eurycephalus) mushroom gobies; the range of the latter includes not only the Sea of Azov but also waters of the Black Sea coast of the Crimean Peninsula; these conclusions are supported by preliminary molecular genetic studies. Based on the obtained results of intraspecific morphological variability of species, we propose morphological characteristics for identification of adult P. syrman and P. odessicus, as well as a specific set of characteristics to identify juvenile (body length less than 50 mm) P. syrman, P. kessleri, and P. odessicus. We reveal differences in the karyotype structure of P. syrman from populations of the Sasyk Lake and the Don River, which do not differ in terms of external morphological characteristics and variability of cytochrome b haplotypes. The need for further research of phylogeography and morphological and karyological variability of P. syrman sensu lato is assumed.  相似文献   

7.
We review species of the genus Lepotrema Ozaki, 1932 from marine fishes in the Indo-West Pacific. Prior to the present study six species were recognised. Here we propose eight new species on the basis of combined morphological and molecular analysis: Lepotrema acanthochromidis n. sp. ex Acanthochromis polyacanthus from the Great Barrier Reef (GBR); Lepotrema hemitaurichthydis n. sp. ex Hemitaurichthys polylepis and H. thompsoni from Palau and French Polynesia; Lepotrema melichthydis n. sp. ex Melichthys vidua from Palau and the GBR; Lepotrema amansis n. sp. ex Amanses scopas from the GBR; Lepotrema cirripectis n. sp. ex Cirripectes filamentosus, C. chelomatus and C. stigmaticus from the GBR; Lepotrema justinei n. sp. ex Sufflamen fraenatum from New Caledonia; Lepotrema moretonense n. sp. ex Prionurus microlepidotus, P. maculatus and Selenotoca multifasciata from Moreton Bay; and Lepotrema amblyglyphidodonis n. sp. ex Amblyglyphidodon curacao and Amphipron akyndynos from the GBR. We also report new host records and provide novel molecular data for two known species: Lepotrema adlardi Bray, Cribb & Barker, 1993 and Lepotrema monile Bray & Cribb, 1998. Two new combinations are formed, Lepotrema cylindricum (Wang, 1989) n. comb. (for Preptetos cylindricus) and Lepotrema navodonis (Shen, 1986) n. comb. (for Lepocreadium navodoni). With the exception of a handful of ambiguous records, the evidence is compelling that the host-specificity of species in this genus is overwhelmingly oioxenous or stenoxenous. This renders the host distribution in three orders and ten families especially difficult to explain as many seemingly suitable hosts are not infected. Multi-loci molecular data (ITS2 rDNA, 28S rDNA and cox1 mtDNA) demonstrate that Lepotrema is a good generic concept, but limited variability in sequence data and differences in phylogenies produced for different gene regions make relationships within the genus difficult to define.  相似文献   

8.
Recently, a highly invasive alien species, the zebra mussel Dreissena polymorpha, has colonized Italian aquatic ecosystems that had been previously colonized by another highly invasive alien species—the North American crayfish Procambarus clarkii. This was the first time and world region where these two species met. To evaluate the relative importance of their interactions, we studied prey selection according to its length, as well as prey choice by P. clarkii preying on D. polymorpha in the presence and absence of alternative prey—the freshwater snail Physella acuta. We followed an optimability-based approach, by first estimating the most profitable length of each mollusc and then by conducting a prey choice experiment, on which both species were provided simultaneously to a crayfish with different size combinations. Prey selection was dependent on prey length, handling time and crayfish length for both molluscs. According to our profitability estimates, snails should be more profitable than mussels in the length range 7–10 mm, while for lengths over 11.0 mm, mussels should be more profitable. The results of the prey choice experiment indicated that D. polymorpha length, P. acuta length, and the difference in profitability between the offered individuals were all relevant for the choice of one species over the other by P. clarkii. However, the overall tendency was the choice of the smallest prey, regardless of species, and the estimates of prey profitability were not useful to predict prey choice. Our study shows that D. polymorpha represents a novel prey resource for P. clarkii, even in the presence of an alternative prey, and that zebra mussels may be a preferred prey, especially small-sized individuals (5–10 mm).  相似文献   

9.
Intercontinental introductions are widespread in the genus Spartina, with important ecological and evolutionary consequences. The native or introduced status of Spartina species is then critical with regard to biodiversity assessment, especially for vulnerable Mediterranean coastline ecosystems. Spartina versicolor was first recorded in southern France in 1849, then successively in various places on the European and North-African Mediterranean and Atlantic coasts. This species is considered to be either a European native or an invasive species introduced from North America which has a high morphological similarity to the Atlantic American species Spartina patens. We performed extensive sampling of S. versicolor in Europe and North Africa (from natural populations and herbarium collections) and compared these samples to other European and American Spartina species (including S. patens). Chromosome counts were reported for the first time and revealed that S. versicolor is tetraploid (2n = 4x = 40). Phylogenetic analyses based on chloroplast and nuclear ribosomal DNA sequences did not reveal any molecular variation within S. versicolor. In this species, a single haplotype, that is identical to one haplotype of S. patens, was found in the four chloroplast and the nuclear ribosomal ITS regions investigated. In addition, simple sequence repeat markers were used and revealed a low level of genetic diversity within S. versicolor, suggesting that the introduction of S. versicolor occurred from a narrow genetic pool of S. patens from North America.  相似文献   

10.
Ficus (Moraceae) is a keystone group in tropical and subtropical forests with remarkable diversity of species and taxonomical challenges as a consequence of fig–pollinator coevolution. Ficus subsect. Frutescentiae includes about 30 species that are predominantly shrubs or small trees with Terminalia branching. Many of these species are difficult to delimit morphologically, and the group includes a tangle of uncertain taxa and incorrectly applied names. We conducted a phylogenetic analysis with internal and external transcribed spacer data (ITS and ETS) and data from 18 polymorphic microsatellite loci to evaluate the species status of the most perplexing members of this subsection. The results confirm the monophyly of subsect. Frutescentiae, with F. pedunculosa as sister to the rest. The F. erecta complex comprises approximately 17 taxa: F. erecta, F. abelii, F. boninsimae, F. nishimurae, F. iidaiana, F. gasparriniana var. laceratifolia, F. gasparriniana var. viridescens, F. pyriformis, F. stenophylla, F. fusuiensis, F. fengkaiensis, F. sinociliata, F. tannoensis, F. vaccinioides, F. formosana, F. pandurata, and F. periptera. The last five of these were supported as good species, while the others were not well supported by the present evidence. Evidence also supported the status of the non-F. erecta complex species including. F. pedunculosa, F. ischnopoda, F. heteromorpha, and F. variolosa. Ficus filicauda and F. neriifolia are possibly conspecific. The species status of F. potingensis should be restored and it should be treated as a member of section Eriosycea. Identification of the remaining taxa (F. gasparriniana var. esquirolii, F. ruyuanensis, F. daimingshanensis, F. chapaensis, F. changii, F. trivia, and F. tuphapensis) and their relationships to the F. erecta complex were not clarified. As a whole, only ten species in this subsection are confirmed, one is excluded, one is synonymous, and the others are either unresolved or short of samples. There appears to be a consistent genetic background among these unresolved groups, which suggests that repeated hybridization (as a result of pollinator host shifts) has filled up the interspecific gaps during the fig–pollinator coevolution process.  相似文献   

11.
Micromorphological features of the leaf epidermis and the inner structure of leaf tissues of eight arborescent taxa of the genus Dracaena were analysed using light and scanning electron microscopy. The plants are xeromorphic or mesomorphic. Their leaves are isobilateral and amphistomatic, and the stomata are anomocytic and tetracytic. The mesophyll in all the species is divided into an outer chlorenchyma and a central region with colourless water-storage cells, chlorophyll cells and vascular bundles. Water-storage cells have wall bands and reticulate thickenings on the walls. The article describes and illustrates several new quantitative and qualitative leaf characters of the dragon tree group. Our findings can be used to identify the dragon tree group leaves, while the shape of epidermal cells and stomata types may be useful in the identification and classification of fragments of fossil leaves. We conclude that D. ombet and D. schizantha are not two distinct species, but should be treated as subspecies of D. ombet. Leaf characters, especially stomata depth on adaxial epidermis, height of adaxial epidermal cells and the presence and thickness of hypodermal fibre bundles markedly differ between geographical groups: Macaronesian species (D. draco and D. tamaranae), the species found in East Africa and Arabian Peninsula (D. ombet subsp. ombet, D. ombet subsp. schizantha, D. serrulata and D. cinnabari) and Southeast Asian species (D. kaweesakii and D. jayniana).  相似文献   

12.
We studied the historical prevalence of the invasive and pathogenic chytrid fungus Batrachochytrium dendrobatidis (Bd) among amphibians from the Bolivian Andes. Our aim was also to determine its geographic pattern of dispersion, and a potential host taxonomic signature. We collected frog tissue samples from nine museum collections covering a period from 1863 to 2005 and from the field during 2009–2016. Bd was diagnosed via quantitative PCR in 599 individuals of 17 genera and 54 species. We found an overall Bd prevalence of 41% among 44 species tested. The first incidence of Bd was from a Telmatobius culeus in 1863; this is the earliest report of detection for this pathogen in the world. Results reveal a non-random historical and geographical pattern of Bd occurrence and amphibian declines that suggests the presence of two different invasive strains, an ancient endemic and a more recent introduction. Prevalence of Bd increased significantly by the mid-1990s, particularly in the cloud-forests, and this is coincident with the timing of drastic amphibian declines. In contrast, amphibians occurring in drier altiplano habitats have persisted in spite of Bd presence. We hypothesize that the early 1990s, and the cloud-forests in central Bolivia were the center of an epidemic surge of Bd that took its toll on many species, especially in the genus Telmatobius. Further sampling of cloud-forest species, and ongoing genetic studies of Bd isolates from Bolivia should help resolve the history of this invasive pathogen and test hypotheses on the differential response of endangered hosts.  相似文献   

13.
Bactrocera carambolae and B. dorsalis (Diptera: Tephritidae) are extremely destructive pests of fruits and vegetables in the Asia-Pacific region. Earlier reports have described that B. carambolae and B. dorsalis, respectively, use mainly star fruit and mango, suggesting a certain level of host partitioning which can be ascribed neither to differences in larval food qualities nor host-specific parasitoid mortality. This study specifically examined reproductive interference (antagonistic sexual interaction) between B. carambolae and B. dorsalis as a potential factor strongly affecting their host partitioning. We observed mating behaviors, especially interspecific courtships and mating, by cohabiting the conspecific and heterospecific pairs together. Consequently, we quantified their effects on the reproductive success of females. Males of both species frequently courted their own females, but they also courted females of other species. Courtship refusal by females was not selective in males of either species. This incomplete discrimination of both sexes led to frequent occurrences of interspecific sexual interactions in both species, but only B. carambolae females showed reduced reproductive success. These results suggest that B. dorsalis, superior in reproductive interference, can occupy high-quality mango, whereas B. carambolae, inferior in reproductive interference, must use low-quality star fruit.  相似文献   

14.
Type and reference strains of members of the onygenalean family Arthrodermataceae have been sequenced for rDNA ITS and partial LSU, the ribosomal 60S protein, and fragments of β-tubulin and translation elongation factor 3. The resulting phylogenetic trees showed a large degree of correspondence, and topologies matched those of earlier published phylogenies demonstrating that the phylogenetic representation of dermatophytes and dermatophyte-like fungi has reached an acceptable level of stability. All trees showed Trichophyton to be polyphyletic. In the present paper, Trichophyton is restricted to mainly the derived clade, resulting in classification of nearly all anthropophilic dermatophytes in Trichophyton and Epidermophyton, along with some zoophilic species that regularly infect humans. Microsporum is restricted to some species around M. canis, while the geophilic species and zoophilic species that are more remote from the human sphere are divided over Arthroderma, Lophophyton and Nannizzia. A new genus Guarromyces is proposed for Keratinomyces ceretanicus. Thirteen new combinations are proposed; in an overview of all described species it is noted that the largest number of novelties was introduced during the decades 1920–1940, when morphological characters were used in addition to clinical features. Species are neo- or epi-typified where necessary, which was the case in Arthroderma curreyi, Epidermophyton floccosum, Lophophyton gallinae, Trichophyton equinum, T. mentagrophytes, T. quinckeanum, T. schoenleinii, T. soudanense, and T. verrucosum. In the newly proposed taxonomy, Trichophyton contains 16 species, Epidermophyton one species, Nannizzia 9 species, Microsporum 3 species, Lophophyton 1 species, Arthroderma 21 species and Ctenomyces 1 species, but more detailed studies remain needed to establish species borderlines. Each species now has a single valid name. Two new genera are introduced: Guarromyces and Paraphyton. The number of genera has increased, but species that are relevant to routine diagnostics now belong to smaller groups, which enhances their identification.  相似文献   

15.
We described the life cycles of 17 riffle-dwelling mayfly species in a central Japanese stream. Both species of Baetidae (Alainites yoshinensis Gose and Baetis thermicus Uéno) and two of nine species of Heptageniidae (Ecdyonurus scalaris Kluge and Epeorus latifolium Uéno/l-nigrus Matsumura) in this stream were multivoltine (more than one generation per year). Seven other heptageniid species (two unidentified species of Cinygmula, Epeorus aesculus Imanishi, E. curvatulus Matsumura, E. ikanonis Takahashi, E. napaeus Imanishi, and Rhithrogena japonica Uéno) and all six species of Ephemerellidae [Cincticostella elongatula (McLachlan), C. nigra (Uéno), Drunella basalis (Imanishi), D. ishiyamana Matsumura, D. sachalinensis (Matsumura), and D. trispina (Uéno)] were essentially univoltine.  相似文献   

16.
We typify and clarify the nomenclature and identity of three species originally described in the fern genus Pellaea. We find Pellaea bongardiana to be illegitimate and recognize it as a synonym of Ormopteris riedelii (= P. riedelii). We also consider Pellaea brasiliensis to be a synonym of O. riedelii. The phylogenetic position of Pellaea flavescens, recently combined in Ormopteris (as O. flavescens), is discussed, and a key to all species of Ormopteris in Brazil is provided.  相似文献   

17.
Species of Cryptocoryneum were taxonomically reassessed on the basis of morphological observations and the results of molecular phylogenetic analysis. Eighteen isolates of Cryptocoryneum species, namely two strains from Africa, three from Europe, and 13 from Japan, were phylogenetically analysed using sequences of nuclear rDNA internal transcribed spacers (ITS) and the partial sequence of the translation elongation factor 1α gene (TEF1). The phylogenetic analysis indicated that Cryptocoryneum species formed a monophyletic clade and were closely related to Lophiotrema (Lophiotremataceae) and Aquasubmersa (incertae sedis) in the Pleosporales (Dothideomycetes). We examined holotype specimens of C. fasciculatum, C. hysterioides, and Torula uniformis and concluded that these species are conspecific, with C. hysterioides having priority. Although C. hysterioides has long been regarded as a synonym of C. condensatum, we consider C. hysterioides to be a distinct species within the genus. We found several cryptic species that were morphologically similar to C. condensatum sensu lato, but that could be separated on the basis of conidial size and the number of conidial arms and conidial septa, characters that seem to be informative for species delimitation within Cryptocoryneum. A total of seven new species, namely C. akitaense, C. brevicondensatum, C. congregatum, C. japonicum, C. longicondensatum, C. paracondensatum, and C. pseudorilstonei, are described and illustrated. A key to species accepted in Cryptocoryneum is provided.  相似文献   

18.
Bulrushes of the genus Bolboschoenus are robust, ecologically important sedges occurring in wetlands, including intertidal marshes and mudflats. Despite their importance and multiple serious threats to their habitats, estuarine Bolboschoenus species remain poorly known. We conducted herbarium and field research in order to document historic and current geographic distributions, characterize the habitats, and assess the conservation status of Bolboschoenus species in the Hudson River Estuary, New York, U.S.A. Three species of Bolboschoenus grow in intertidal zones in the Hudson Estuary. Bolboschoenus fluviatilis occurs in the northern, upstream, and freshwater portion of the estuary with multi-year mean surface salinities of 0.078–2.0 ppt. Bolboschoenus robustus occupies the southernmost, downstream, and brackish to saline portion of the estuary with salinities of 4.9–16 ppt. Bolboschoenus novae-angliae occurs in the slightly to strongly brackish region between the other two species with salinities of 1.8–8.0 ppt. The geographic ranges of B. fluviatilis and B. robustus do not overlap, but B. novae-angliae has short zones of sympatry with each of the other two species. Syntopy of B. novae-angliae with each of the other two species is rare. In the Hudson Estuary, B. fluviatilis is secure, but B. novae-angliae and B. robustus are critically imperiled. Threats to future survival of Bolboschoenus species in the Hudson Estuary include competition from invasive plant species (especially Phragmites australis), eutrophication resulting from excess nutrient pollution, and habitat destruction. Our data and analyses provide critical new information for management of existing environmental problems and planned habitat restoration efforts in the Hudson River Estuary.  相似文献   

19.
Harmonia axyridis Pallas (1773) (Coleoptera: Coccinellidae) is the well-studied system of invasive insect species. Native and invasive parts of the area of H. axyridis are isolated geographically. We studied the species composition and the distribution of bacterial symbionts Spiroplasma and Rickettsia in seven localities of the native area and six localities of the invasive area of H. axyridis. Rickettsia was detected in H. axyridis populations for the first time. We found that the proportion of beetles infected with Rickettsia in native and invasive populations of H. axyridis is about 0.03. Spiroplasma was found only in native populations of H. axyridis. The proportion of infected individuals with Spiroplasma in native populations of H. axyridis is about 0.08. All studied native populations of H. axyridis are infected with Spiroplasma, while all invasive populations are not. We discuss the possible influence of Spiroplasma and Rickettsia in the formation of invasive populations of H. axyridis.  相似文献   

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