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Five new species of the subgenus Xanthempis Bezzi are described from the Caucasus: Empis (Xanthempis) annae sp. n. (Russia: Krasnodar Territory), E. (X.) grichanovi sp. n. (Russia: Krasnodar Territory; Georgia), E. (X.) pseudoconcolor sp. n. (Russia: Krasnodar and Stavropol territories; Georgia: Abkhazia), E. (X.) teberdaensis sp. n. (Russia: Karachay-Cherkessia), and E. (X.) zamotajlovi sp. n. (Russia: Krasnodar Territory and Adygea). The females of E. (X.) alanica Shamshev and E. (X.) kovalevi Shamshev are described for the first time. New data on the distribution of some previously described species are reported. The geographical distribution of Xanthempis is discussed. A key to Xanthempis species from the Caucasus is compiled.  相似文献   

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To improve baseline data for the developing truffle industry in British Columbia, we compiled existing Tuber species sequences from published and unpublished studies and generated new ITS sequences for truffles belonging to Tuber collected in the province. In doing so, we obtained evidence that 13 species of Tuber occur in the province, including six introduced and seven native species, two of which are putative undescribed species. Of the native species, the Tuber anniae species complex is widely distributed in the province while Tuber beyerlei appears to be much more restricted in distribution. Four of the introduced species have commercial value (Tuber melanosporum, Tuber aestivum, Tuber brumale, and Tuber borchii) as do two of the native species (Tuber gibbosum and Tuber oregonense). Focused sampling on likely tree hosts, both hardwood and Pinaceae species, as well as in currently unexplored parts of the province seems likely to expand our knowledge of the diversity and distribution of Tuber species in British Columbia.  相似文献   

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Taxonomy and geographical distribution of diatom taxa from the genus Eunotia are discussed. Fourteen Eunotia species are found in aquatic ecosystems of Central and South-Eastern Vietnam: E. indosinica, E. karveerensis, E. sulcata, E. cf. vumbae, E. novaecaledonica, E. naegelii, E. paramuscicola, E. rabenhorstii, E. tropica, E. sioliopsis, E. australominor, E. mucophila. Two species which are new for science are described Eunotia skvortzovii Glushchenko & Kulikovskiy sp. nov. and Eunotia fogedii Glushchenko & Kulikovskiy sp. nov. Eunotia sulcata Hustedt ex Glushchenko & Kulikovskiy is validated. The species are illustrated by original LM and SEM microphotographs. The main qualitative and quantitative taxonomic data are given. The distribution is found species is discussed.  相似文献   

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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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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   

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Mistletoe infection between conspecific and interspecific hosts can be restricted by seed dispersal, host-mistletoe compatibility and abiotic factors, yet no studies have linked mistletoe infection patterns and pollination together for understanding mistletoe distribution at a local scale. Psittacanthus calyculatus (Loranthaceae) is a hemiparasitic plant with a broad host range across its geographic distribution. The potential for local host adaptation has been shown using cross-inoculation experiments, in which plants of mistletoe seeds collected from a given host are more likely to survive when they are inoculated on conspecific host trees compared with those inoculated on other host provenances. Here we evaluate host adaptation by describing the local patterns of infection (prevalence and intensity) of P. calyculatus mistletoes on three native host tree species (Alnus acuminata, Quercus crassipes, Salix bonplandiana) and one introduced species (Populus alba) and carried out cross-pollination experiments to examine how pollination affects infection patterns of different host species. Mistletoe infection prevalence (proportion of infection) and infection intensity (mean number of mistletoes per tree) were in general disproportional with respect to the availability of native host tree species but higher to that of non-native host tree species. Cross-pollination experiments showed higher mating success on the native host tree species, suggesting higher local adaptation to specially Q. crassipes. The observed spatial distribution of host tree species and mistletoe infection along with the non-random mating could contribute to local genetic structuring of mistletoe populations.  相似文献   

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Endelus (Kubaniellus) indicus sp. n. from India, E. (K.) lao sp. n. and E. (K.) khnzoriani sp. n. from Laos, E. (s. str.) sausai sp. n. from China, and E. (s. str.) dembickyi sp. n. from India are described, the two latter species are included in the Endelus bicarinatus Théry, 1932 species-group recently established by the author. E. collinus Obenberger, 1922 is included in this group; lectotype of this species is designated. Keys to species of the subgenus Kubaniellus and of the E. collinus group are provided. E. (K.) kareni Kalashian is for the first time recorded for Shaanxi Prov., E. pacholatkoi Kalashian, E. smaragdinus Desc. et Vill., and E collinus Obenb., for Laos (the latter species, also for Myanmar).  相似文献   

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Rhizomatosae is a taxonomic section of the South American genus Arachis, whose diagnostic character is the presence of rhizomes in all its species. This section is of particular evolutionary interest because it has three polyploid (A. pseudovillosa, A. nitida and A. glabrata, 2n?=?4x?=?40) and only one diploid (A. burkartii, 2n?=?2x?=?20) species. The phylogenetic relationships of these species as well as the polyploidy nature and the origin of the tetraploids are still controversial. The present study provides an exhaustive analysis of the karyotypes of all rhizomatous species and six closely related diploid species of the sections Erectoides and Procumbentes by cytogenetic mapping of DAPI/CMA heterochromatin bands and 5S and 18–26S rDNA loci. Chromosome banding showed variation in the DAPI heterochromatin distribution pattern, which, together with the number and distribution of rDNA loci, allowed the characterization of all species studied here. The bulk of chromosomal markers suggest that the three rhizomatous tetraploid species constitute a natural group and may have at least one common diploid ancestor. The cytogenetic data of the diploid species analyzed evidenced that the only rhizomatous diploid species—A. burkartii—has a karyotype pattern different from those of the rhizomatous tetraploids, showing that it is not likely the genome donor of the tetraploids and the non-monophyletic nature of the section Rhizomatosae. Thus, the tetraploid species should be excluded from the R genome, which should remain exclusively for A. burkartii. Instead, the karyotype features of these tetraploids are compatible with those of different species of the sections Erectoides and Procumbentes (E genome species), suggesting the hypothesis of multiple origins of these tetraploids. In addition, the polyploid nature and the group of diploid species closer to the tetraploids are discussed.  相似文献   

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The North European species of the Hygrophorus agathosmus group in subsection Tephroleuci were studied. Three new species are identified based on morphology, ecology and sequence data. Two species are associated with Pinus spp. One of these is described here as H. suaveolens, while the other one is only known from one locality in the Nordic countries and seems to have a more South European distribution range. A closely related sister species to H. agathosmus is identified based on ITS sequence data, H. cf. agathosmus. It is confirmed to have an intercontinental distribution range and to be associated with Picea spp. probably on more acidic to neutral soil, whereas H. agathosmus s.s. has a more limited North-East European distribution range and occurs in older and rich Picea abies forests. A neotype for H. agathosmus is here selected from South Sweden. Hygrophorus agathosmus f. albus and H. agathosmus f. aureofloccosus are confirmed as forms. No genetic differences in the ITS region between specimens with grey cap colour and the two forms were observed. A key to the species in Northern Europe is provided.  相似文献   

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Examination of three species of batfishes (Teleostei: Epphippidae) from off Lizard and Heron Islands on the Great Barrier Reef led to the discovery of specimens of the trematode genus Paradiscogaster Yamaguti, 1934 (Digenea: Faustulidae). Morphological analysis demonstrated that the new specimens represented four morphotypes which we interpret to be new species: Paradiscogaster martini n. sp., P. vichovae n. sp. and P. brayi n. sp. from Platax orbicularis (Forsskål) and P. pinnatus (Linnaeus) off Lizard Island, and P. nitschkei n. sp. from P. teira (Forsskål) off Heron Island. Published material was re-examined and the specimens identified as P. chaetodontis okinawensis Yamaguti, 1971 from P. pinnatus from Okinawa, Japan, actually represent the new species P. brayi n. sp., demonstrating that some species of Paradiscogaster have wide geographical distributions. ITS2 rDNA data for the four morphotypes differ by 4–39 base pairs confirming the delineation of the four species proposed. A feature of this study is the recognition of Platax spp. as an important host group for Paradiscogaster, with the new species placing them as the second richest host group for these parasites after the Chaetodontidae.  相似文献   

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Trissolcus japonicus Ashmead (Hymenoptera: Scelionidae) is an endoparasitoid of the eggs of the brown marmorated stink bug, Halyomorpha halys Stål (Hemiptera: Pentatomidae), a major agricultural pest native to China, Japan, South Korea and Taiwan. We used CLIMEX to estimate the potential global distribution of T. japonicus with particular reference to New Zealand. In its native range the model predicts the presence, or a potential expansion, of T. japonicus into most of humid-subtropical and humid-continental areas. Globally, the model projects that many temperate, Mediterranean and subtropical areas could suit the establishment of T. japonicus. In New Zealand, the north appears moderately to highly suitable for T. japonicus, while southern regions are mostly marginal. The risk posed by T. japonicus to non-target species in New Zealand is predicted to vary between different non-targets. CLIMEX projections of the potential distribution of T. japonicus provide guidance for release sites of this parasitoid if approved for importation and release in New Zealand.  相似文献   

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Since their recent introductions into Florida waters, three sessile invertebrates [Perna viridis (Asian green mussel), Mytella charruana (charru mussel) and Megabalanus coccopoma (pink titan acorn barnacle)] have expanded their range along the Atlantic coast in estuarine waters. Little research has been done to understand how these nonnative species interact with the ecologically and economically important eastern oyster Crassostrea virginica. To assess the potential effects of P. viridis, M. charruana and M. coccopoma on C. virginica, the following questions were addressed in manipulative experiments. (1) Does the presence of nonnative species decrease oyster larval settlement? (2) Do oyster larvae avoid settling on nonnative species? (3) Do nonnative species decrease survival of juvenile oysters (spat)? (4) Do nonnative species hinder spat growth? We included two controls: absence of nonnative species and presence of the native mussel Geukensia demissa. The nonnative species influenced settlement, growth and survival of C. virginica in different ways. M. coccopoma and P. viridis negatively influenced larval settlement, whereas M. charruana had no influence on the total number of settled larvae. Oyster larvae avoided settling on all three nonnative species and the native G. demissa. Both nonnative mussels negatively affected survival of juvenile oysters but only M. charruana also reduced spat growth. The native mussel, G. demissa, had no negative impacts on total settlement, survival and growth of C. virginica; in fact, it increased larval settlement in some trials. These three nonnative species should be classified as invasive because all had negative effects on native C. virginica.  相似文献   

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Recently, masses of the ant Formica (Serviformica) fuscocinerea (Forel) have been occurring at numerous sites in Southern Germany. Although F. fuscocinerea is native to Southern Germany, these mass occurrences resemble ant invasions in density and dominance. This study aimed to investigate the underlying mechanisms that promote sudden mass occurrence of a previously inconspicuous ant species within its native range. To estimate the competitive dominance of F. fuscocinerea, species occurrence and abundance considering biotic and abiotic parameters were studied in a natural habitat where F. fuscocinerea co-occurred with two other common ant species, Myrmica ruginodis (Nylander) and Lasius niger (Linnaeus). To understand the species’ distribution in the field, laboratory experiments on interspecific competition were conducted. Finally, the colony structure of F. fuscocinerea was investigated with intraspecific aggression tests. Formica fuscocinerea dominated an area that, as indicated by strongly frequented foraging trails on the trees, provided important food sources, e.g. trophobionts, to the ants. Other ant species coexisted only at the periphery of the F. fuscocinerea range. Laboratory experiments revealed F. fuscocinerea as highly dominant species. Additionally, F. fuscocinerea showed a complete lack of intraspecific aggression between ants originating from distances up to 58 km, indicating weak or nonexistent behavioral boundaries among ants of physically separated nests. Since extraordinarily high worker densities, strong interspecific dominance and a lack of colony boundaries within supercolonies are considered to be important traits of several invasive ant species we conclude that the same traits also promote the dominance of F. fuscocinerea.  相似文献   

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The occurrence of non-native species at high densities may generate competition for resources and possibly exclude native species in various environments. We evaluated the effects of increased densities of the non-native invasive macrophyte Hydrilla verticillata on the growth of the native species Egeria najas in different sediment types and with only root interactions or root?+?shoot interactions. We tested the hypothesis that the effect of the invasive on the native species is density dependent and that it is greater when competition for light and nutrients occurs (root?+?shoot interactions). The results of these experiments demonstrated that increased density of the invasive species H. verticillata significantly decreased the growth of the native species independent of sediment type (sand or mud sediments). When plants competed for water and sediment resources (root?+?shoot interactions), the native species was more impacted by the invasive than when they competed only for water resources (only shoots interacting). Our results show that E. najas is probably unable to colonize sites highly colonized by hydrilla, and this applies to both sand and mud sediments. This outcome suggests that H. verticillata is a threat for E. najas and likely other native submerged species in South America.  相似文献   

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Revegetation using native species requires the development of seed transfer zones that capture genetic distinctiveness and adaptive potentials while avoiding potential maladaptation and genetic contamination by exotic genotypes. Delineation based on phylogeographic information has recently been used to establish seed transfer zones; however, only a few herbaceous species that are suitable for revegetation have been investigated in the temperate regions of Japan. We investigated the phylogeography of non-coding regions of chloroplast DNA of ten native species in the temperate regions of Japan. Although no species showed clear-cut geographical distributions of the 2–14 haplotypes identified, spatially constrained Bayesian clustering showed two clusters in five species (Calamagrostis epigejos, Eragrostis ferruginea, Imperata cylindrica, Microstegium japonicum, and Microstegium vimineum) but not for others. Posterior modes of clusters for I. cylindrica and M. vimineum showed delineations at Chubu (the middle of Honshu Island), which divide the study region into northeastern and southwestern regions, indicating that these species had recovered from glacial refugia. Posterior mode of cluster for E. ferruginea showed that one consists of a coastal zone along the Pacific Ocean side of western Japan, while the other consists of the remaining area, indicating range expansion from south coast to north. Delineation of C. epigejos and M. japonicum were unclear. The mixed results indicated that establishing seed transfer zones for herbaceous species in Japan will require phylogeographical studies on a wide range of species that may be suitable for revegetation.  相似文献   

20.
The three species of banded newt (genus Ommatotriton) are endemic to the Near East. Recently an introduced banded newt population was discovered in Catalonia, Spain. To determine the species involved and the geographical source, we genotyped 11 individuals for one mitochondrial and two nuclear genetic markers, and compared the observed haplotypes to a range-wide phylogeography of Ommatotriton. All haplotypes identified in Spain are identical to haplotypes known from the native range. The mitochondrial haplotypes derive from O. ophryticus and were originally recorded in northeast Turkey. The nuclear haplotypes reveal that all individuals are genetically admixed between O. ophryticus and O. nesterovi. While the geographical resolution for the nuclear markers is low, the source of the O. nesterovi ancestry must be Turkey, as this species is a Turkish endemic. Species distribution models suggest a large potential distribution for the two Ommatotriton species, extending over northern Iberia and southern France. The ecology of hybrids can differ substantially from that of the parent species, making the impact of the Spanish hybrid banded newt population difficult to predict.  相似文献   

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