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1.
Pang KL  Chiang MW  Vrijmoed LL 《Mycologia》2008,100(2):291-295
Information on the diversity and ecology of arctic marine fungi is lacking. During a short visit to Longyearbyen (78 degrees 13'N 15 degrees 33'E), Svalbard, Norway, a new marine fungus growing on driftwood collected at the shore was encountered. This taxon belongs to the Halosphaeriales (Ascomycota), a fungal order of mostly marine species. Havispora longyearbyenensis gen. et sp. nov. is morphologically similar to Nautosphaeria and Nereiospora, all with tufts of appendages at polar and equatorial positions of the ascospore but differing in color and septation of the ascospore and morphology and ontogeny of the ascospore appendage.  相似文献   

2.
Dichotomously branched stem fragments with crowded, spirally arranged, trifurcate leaf base remains from the type area of the Maastrichtian (Late Cretaceous; SE Netherlands, NE Belgium) are described as a new genus and species: Mosacaulis spinifer Van der Ham et Van Konijnenburg-van Cittert. They are interpreted as fossils of (pseudo)herbaceous axes with densely spaced, semi-amplexicaul leaves arranged in low spirals, with reproductive structures (sporangia?, prophylls associated with flowering axes?) attached to the adaxial sides of the leaf bases. M. spinifer is considered to be of unknown affinity (incertae sedis), showing resemblances with such disparate lineages as lycopsids and angiosperms. Its seagrass-like habit, gregarious occurrence, the association with genuine seagrass and a diverse marine fauna (including epibionts on the stems), and the absence of any terrigenous material, remains of land plants and terrestrial palynomorphs suggest that M. spinifer grew in a fully marine environment.  相似文献   

3.
Summary Two new nitrite oxidizing bacteria for which the names Nitrococcus mobilis and Nitrospina gracilis are proposed were isolated from the marine environment. Nitrococcus mobilis was cultured from South Pacific waters and it is a large motile coccus with unique tubular cytomembranes. Nitrospina gracilis was isolated from South Atlantic waters and it is a long slender rod which lacks an extensive cytomembrane system. Both are obligate marine organisms and both are obligate chemoautotrophs. The fine structure of these organisms is detailed.Contribution No. 2631 from the Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543.  相似文献   

4.
In habitats where nitrogen is the limiting factor, carnivorous fungi gain an advantage by preying on nematodes and other microorganisms. These fungi are abundant in modern terrestrial ecosystems, but they are not predestined for preservation as fossils. Conclusions on their evolutionary history are therefore mainly based on molecular studies that are generally limited to those taxa that have survived until today. Here we present a fossil dimorphic fungus that was found in Late Albian amber from southwestern France. This fungus possessed unicellular hyphal rings as trapping devices and formed blastospores from which a yeast stage developed. The fossil probably represents an anamorph of an ascomycete and is described as Palaeoanellus dimorphus gen. et sp. nov. Because predatory fungi with regular yeast stages are not known from modern ecosystems, the fungus is assumed to not be related to any Recent carnivorous fungus and to belong to an extinct lineage of carnivorous fungi. The inclusions represent the only record of fossil fungi that developed trapping devices, so far. The fungus lived c. 100 million years ago in a limnetic-terrestrial microhabitat, and it was a part of a highly diverse biocenosis at the forest floor of a Cretaceous coastal amber forest.  相似文献   

5.
Two novel genera of restricted facultative methylotrophs are described; both Methylosulfonomonas and Marinosulfonomonas are unique in being able to grow on methanesulfonic acid as their sole source of carbon and energy. Five identical strains of Methylosulfonomonas were isolated from diverse soil samples in England and were shown to differ in their morphology, physiology, DNA base composition, molecular genetics, and 16S rDNA sequences from the two marine strains of Marinosulfonomonas, which were isolated from British coastal waters. The marine strains were almost indistinguishable from each other and are considered to be strains of one species. Type species of each genus have been identified and named Methylosulfonomonas methylovora (strain M2) and Marinosulfonomonas methylotropha (strain PSCH4). Phylogenetic analysis using 16S rDNA sequencing places both genera in the α-Proteobacteria. Methylosulfonomonas is a discrete lineage within the α-2 subgroup and is not related closely to any other known bacterial genus. The Marinosulfonomonas strains form a monophyletic cluster in the α-3 subgroup of the Proteobacteria with Roseobacter spp. and some other partially characterized marine bacteria, but they are distinct from these at the genus level. This work shows that the isolation of bacteria with a unique biochemical character, the ability to grow on methanesulfonic acid as energy and carbon substrate, has resulted in the identification of two novel genera of methylotrophs that are unrelated to any other extant methylotroph genera. Received: 19 July 1996 / Accepted: 7 October 1996  相似文献   

6.
A new species of Magnolia sect. Gwillimia DC., Magnoliaceae from Vietnam is described and illustrated. Magnolia tiepii is recognized from southern Vietnam, where it occurs in Khanh Vinh slope, Khanh Vinh District, Khanh Hoa Province. It is distinguished from the closely related M. henryi by having narrowly cuneate leaf blade, short petiole, stipular scar at the base of the leaf blade, short peduncle and ellipsoid fruit.  相似文献   

7.
The isolation of two entomopathogenic fungi from Forcipomyia marksae larvae collected in leaf axils of Colocasia macrorrhiza in northeastern Queensland rain forests is reported. An oomycete, in which the zoospores complete their development wholly within the sporangium and are discharged through a short papillar extension, is described as a new genus and species, Crypticola clavulifera. A strain of the well-known oomycete, Lagenidium giganteum, was isolated from F. marksae--the first record of this fungus infecting a member of the Ceratopogonidae. The pathogenesis and zoosporogenesis of the two fungi in mosquito and ceratopogonid larvae are described.  相似文献   

8.
Gaultheria gonggashanensis P. W. Fritsch & Lu Lu, a new species from western Sichuan Province, China, is described and illustrated. This species belongs to Gaultheria ser. Trichophyllae Airy Shaw and is most similar to G. sinensis J. Anthony, but differs by its longer stem setae, glabrous petioles and leaf blade midveins adaxially, thick‐chartaceous to subcoriaceous leaf blades, larger calyx lobes, and smaller anther thecae. The species is known with certainty only from the Hailuo Valley on the east slope of Mount Gongga in the Daxue Range.  相似文献   

9.
Eucyclops dumonti sp.nov. from Central Mongolia   总被引:8,自引:0,他引:8  
Alekseev  Victor R. 《Hydrobiologia》2000,441(1):63-71
Anthropogenic biological introductions have captured the attention of marine scientists and resource managers in recent years. Human-mediated marine bioinvasions are presently acknowledged as often ecologically and financially devastating events. Despite recent increases in scientific interest and financial resources devoted to nonindigenous nuisance species globally, fundamental questions pertaining to taxonomic identity, geographic source, introduction vector and invasive population dynamics frequently remain unanswered. Ecological surveys based on photometric and observational methods are unable to identify cryptogenic taxa, source populations, multiple introductions, or genetic diversity. The twofold goal of this paper is to discuss the application of molecular genetic techniques to fundamental ecological questions pertaining to bioinvasions and to demonstrate the utility of DNA technology in providing data useful in the development of predictive models for marine bioinvasion science.  相似文献   

10.
Two new species of aerobic, gram-negative, peritrichously flagellated or nonmotile marine bacteria usually forming star-shaped aggregates were isolated from northeastern Atlantic Ocean bottom sediments. These organisms resembled eight star-shaped-aggregate-forming bacterial species from the Baltic Sea originally ascribed to the genus Agrobacterium but not included on the Approved Lists of Bacterial Names because of their questionable relationships to true agrobacteria. These two sets of star-shaped-aggregate-forming bacteria were compared by means of phenotypic data, DNA base compositions, DNA-DNA relatedness, and one-dimensional electrophoretic analysis of low-molecular-weight RNAs (5S rRNA and tRNA). According to the results of genotyping, the northeastern Atlantic Ocean isolates and three of the Baltic Sea species formed a group of closely related bacteria that could not be excluded from the genus Agrobacterium with certainty. Until more genotypic data are available, these five marine species are regarded as a distinct subdivision of the genus Agrobacterium consisting of Agrobacterium atlanticum sp. nov. (type strain, 1480T = DSM 5823T), A. meteori sp. nov. (type strain, 1513T = DSM 5824T), A. ferrugineum sp. nov. nom. rev. emend. (type strain, ATCC 25652T), A. gelatinovorum sp. nov. nom. rev. emend. (type strain, ATCC 25655T), and A. stellulatum sp. nov. nom. rev. emend. (type strain, ATCC 15215T). "A. aggregatum" proved to be a later subjective synonym of A. stellulatum, which had priority. The remaining four Baltic Sea species, "A. agile," "A. kieliense," "A. luteum," and "A. sanguineum," could not be placed in the new subdivision of Agrobacterium.  相似文献   

11.
Five strains of rod-shaped, Gram-negative, non-sporing, strictly anaerobic bacteria were isolated from limnic and marine mud samples with gallic acid or phloroglucinol as sole substrate. All strains grew in defined mineral media without any growth factors; marine isolates required salt concentrations higher than 1% for growth, two freshwater strains only thrived in freshwater medium. Gallic acid, pyrogallol, 2,4,6-trihydroxybenzoic acid, and phloroglucinol were the only substrates utilized and were fermented stoichiometrically to 3 mol acetate (and 1 mol CO2) per mol with a growth yield of 10g cell dry weight per mol of substrate. Neither sulfate, sulfur, nor nitrate were reduced. The DNA base ratio was 51.8% guanine plus cytosine. A marine isolate, Ma Gal 2, is described as type strain of a new genus and species, Pelobacter acidigallici gen. nov. sp. nov., in the family Bacteroidaceae. In coculture with Acetobacterium woodii, the new isolates converted also syringic acid completely to acetate. Cocultures with Methanosarcina barkeri converted the respective substrates completely to methane and carbon dioxide.  相似文献   

12.
13.
A survey was conducted to identify fungi associated with leaf diseases of ornamental herbs, including Christ plant, dracaena, rose geranium, rose periwinkle and treasure flower, in Ahvaz, southwestern Iran. Twenty‐five symptomatic herbs were collected and studied, which led to the isolation of seven Phoma‐like strains belonging to four taxa. These fungi were characterised based on DNA sequence data for the partial large subunit 28S nrDNA (LSU‐D1/D2), the internal transcribed spacer 1 and 2 and 5.8S nrDNA (ITS) and part of the β‐tubulin (tub2) gene regions. A multi‐locus‐based phylogeny, in combination with morphology, allowed for the identification of Allophoma hayatii, A. labilis, A. tropica and a novel species of the genus Ectophoma. Ectophoma iranica sp. nov. is morphologically and genetically distinctive from previously described species. In pathogenicity tests, the two strains of E. iranica (CBS 144681 and IRAN 3354C) caused leaf spot symptoms on leaves of Catharanthus roseus. New host plant species and records for A. hayatii, A. labilis and A. tropica are reported, plus further emended characterization of A. hayatii.  相似文献   

14.
From marine and freshwater mud samples and from human saliva new strictly anaerobic, Gram-negative, nonsporeforming bacteria were isolated growing with succinate as sole source of carbon and energy. All strains grew in defined mineral media containing at least 1% sodium chloride. Succinate was stoichiometrically transformed to propionate und carbon dioxide; the growth yield varied between 2.1 and 2.4 g cell dry weight per mol of succinate fermented. In addition to succinate, only fumarate, l-aspartate, l-malate, oxaloacetate and pyruvate, were utilized and were stoichiometrically fermented to propionate and acetate. Yeast extract was not fermented but enhanced growth rates and yields. Neither sulfate, sulfur, nor nitrate were reduced. The DNA base ratio was 33.9±0.3 mol % guanine plus cytosine. A marine isolate, strain Gra Succ 2, is described as type strain of a new species, Propionigenium modestum gen. nov. sp. nov., in the family Bacteroidaceae.  相似文献   

15.
Didymodon mesopapillosus J. Kou, X.‐M. Shao & C. Feng is described and illustrated as a new species from Tibet, China. It is characterized mainly by its ovate to ovate‐lanceolate leaves appressed to weakly erect when dry, margins recurved from leaf base to apex, laminal cell superficial walls markedly thicker than the internal walls, laminal papillae present only on both sides of costa, short‐excurrent costa, undifferentiated basal cells and differentiated perichaetial leaves. This species is compared with similar species and its ecology is discussed.  相似文献   

16.
Sulfate-reducing bacteria with oval to rod-shaped cells (strains AcRS1, AcRS2) and vibrio-shaped cells (strains AcRM3, AcRM4, AcRM5) differing by size were isolated from anaerobic marine sediment with acetate as the only electron donor. A vibrio-shaped type (strain AcKo) was also isolated from freshwater sediment. Two strains (AcRS1, AcRM3) used ethanol and pyruvate in addition to acetate, and one strain (AcRS1) grew autotrophically with H2, sulfate and CO2. Higher fatty acids or lactate were never utilized. All isolates were able to grow in ammonia-free medium in the presence of N2. Nitrogenase activity under such conditions was demonstrated by the acetylene reduction test. The facultatively lithoautotrophic strain (AcRS1), a strain (AcRS2) with unusually large cells (2×5 m), and a vibrio-shaped strain (AcRM3) are described as new Desulfobacter species, D. hydrogenophilus, D. latus, and D. curvatus, respectively.  相似文献   

17.
Nakamura  Kazuyo  Hatai  Kishio 《Mycoscience》1994,35(4):383-389
A new species ofAtkinsiella (Lagenidiales, Oomycetes),Atkinsiella parasitica is described and illustrated. It was isolated from the eggs and bodies of a rotifer,Brachionus plicatilis, with fungal infection in 1992. The rotifer was reared in a hatchery as the first food supply for seed production of crustaceans and fishes. The fungus is characterized by producing monoplanetic, lateral biflagellate zoospores, and infrequently branched discharge tubes. Optimum temperature for the fungus was 25°C. The fungus was considered an obligate marine fungus, because its growth was observed only on PYGS medium including seawater.  相似文献   

18.
A new species of willow from Crete, named Salix kaptarae Cambria, C. Brullo & Brullo, is described and illustrated. Morphologically, it shows close relationships with species belonging to the S. apennina group, mainly with respect to the leaf shape, and the hairy ovary, capsule and base of stamina filaments. Considerations on its ecology, leaf micro‐morphology and conservation status are also provided.  相似文献   

19.
Four strains of an ascogenous yeast were isolated from the guts of the woodlice species Armadillidium vulgare (Latreille). This yeast differed from all known yeasts by its inability to grow in culture without the presence of a metabolite produced by some common soil fungi such as Cladosporium cladosporioides, Aspergillus alliaceus, and Penicillium spp. Phylogenetic analysis based on 18S rDNA and 26S rDNA (domain D1/D2) sequences indicated that the yeast represents a new taxon in the genus Debaryomyces. The new species Debaryomyces mycophilus is thus proposed. It was, furthermore, shown that the fungal metabolite necessary for growth of D. mycophilus did not provide the yeast with carbon, nitrogen or vitamins. The active compound was partially purified and it was shown that it is a siderophore used by the yeast as a source of iron. The addition of ferrichrome or high concentrations of FeCl(3) to growth media replaced the obligate dependence on a fungal metabolite. Symbiosis among fungi, based on the availability and utilization of iron, is an aspect of mycology that has not previously been recognized. The addition of chelated iron to isolation media could lead to the discovery of many unknown yeasts and fungi.  相似文献   

20.
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