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1.
The occurrence of cossonine weevils of the genus Araucarius Kuschel 1966 is limited to South American Araucaria trees. Adults and larvae of two new species, Araucarius kuscheli spec. nov. and A. crassipunctatus spec. nov. have been found under the bark of Araucaria angustifolia trees in São Francisco de Paula, Rio Grande do Sul, Brazil. A key for the adults of the genus Araucarius including the two new species and the already known two Brazilian and four Chilean species is presented.  相似文献   

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Summary A vigorously nitrogen-fixing bacterium was isolated from a West Bengal soil. Cells from young cultures on nitrogen-deficient agar medium appear as rods measuring approx. 3–6x1.0–1.2 ., with rounded ends and homogeneous cytoplasm. Older cells contain big refractile bodies representing vacuoles and fat deposits and show a wide variation in shape. Short motile cells with a single polar flagellum arise in liquid medium with combined (ammonia) nitrogen. The Gram reation is negative and endospores are not formed.The organism is aerobic but catalase-negative. It grows rather feebly in sugar-free protein media, but in nitrogen-deficient media it produces ah heavy and extremely tenacious growth, of a characteristic uneven appearance on agar and changing from white to dark red-brown. Glucose, fructose, ethanol, glycerol, mannitol and sorbitol are the best sources of carbon. Acid but no gas is formed from several carbohydrates. Nitrogen fixation is slow but may amount to 20–25 mg. per gram glucose or mannitol supplied. Molybdenum stimulates nitrogen fixation strongly and cannot be replaced by vanadium.Various forms of combined nitrogen, especially glutamic acid, are assimilated more readily than free nitrogen. Growth can be initiated within aPh-interval from approx. 5 to 9; growing cultures may be acidified to Ph 4.5 or less.The organism is morphologically, culturally and serologically different from Azotobacter and Beijerinckia and is regarded as representing a new genus.  相似文献   

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A new acanthoecid choanoflagellate species, Acanthocorbis mongolica sp. nov. was found in preserved phytoplankton samples from the freshwater lake Bayan Nuur (Uvs Nuur Basin, NW Mongolia) in concentrations of up to 1.8×10(5)cellsL(-1). It is the first well-documented species of the mainly marine order Acanthoecida to be found in a freshwater lake. The lorica structures were studied with scanning electron microscopy. Key morphological features of the vase-shaped lorica are spine bases that are composed of multiple (2-4) parallel costal strips, and the existence of two transverse costae. The ecological implications of this find are discussed.  相似文献   

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Summary The structure and life cycle of a new genus and species of labyrinthulid, Labyrinthuloides yorkensis, is described from observations of pure cultures. Uninucleate cells are capable of gliding by means of ectoplasmic nets which push or pull the cells across the substrate. The net elements do not enrobe the cells and motility is reversible. Sporulation occurs by successive bipartition or progressive cleavage of the protoplast. Biflagellated zoospores with an anterior tinseled flagellum and posterior whiplash flagellum are formed as are non-replicating amoebae and plasmodia. The fine structure includes centrioles with a single large granule in the lumen and numerous cytoplasmic inclusion bodies with associated membrane complexes. The membrane-inclusion arrays are each found within a delimiting vesicle membrane.Contribution No. 503, Virginia Institute of Marine Science, Gloucester Point, Virginia 23062.Supported in part by the Oceanography Section, National Science Foundation NSF Grant GA-31014.  相似文献   

6.
Aster saxicola W. P. Li & Z. Li, a new species of Asteraceae from southeastern Guizhou province, China, is described and illustrated based on morphological, molecular and cytological data. Morphological comparisons showed that A. saxicola is similar to A. oliganthus, but can be distinguished from the latter by its purple abaxial surface of the lower and middle cauline leaves, cordate‐ovate basal leaves with strigose hairs, outer three‐seriate phyllaries with purple or purplish apex, 9–14 ray florets and 10–18 disk florets. Phylogenetic analyses based on nrDNA ITS, ETS and plastid trnL–F DNA sequence data support that A. saxicola is a distinct species and belongs to Aster subgen. Aster sect. Ageratoides. Cytological observation shows that the new species is diploid with a karyotype formula 2n = 2x = 18 = 16m + 2sm. The new species should be considered endangered (EN) based on the IUCN red list criteria because of its restricted geographic range.  相似文献   

7.
Two novel hypotrichous ciliates, Hemiurosomoida warreni nov. spec. and Hemiurosoma clampi nov. spec., isolated from soil in the Lhalu Wetland and Motuo Virgin Forest in Tibet, respectively, were investigated using live observation and protargol staining. Hemiurosomoida warreni nov. spec. strongly resembles the type species H. longa but can be distinguished by its body size in vivo (110–145 × 30–40 μm vs. 50–100 × 18–40 μm), number of adoral membranelles (25–38 vs. 15–22), and numbers of right (29–39 vs. 14–23) and left (26–35 vs. 13–23) marginal cirri, transverse cirri (3 vs. 4 or 5) and macronuclear nodules (4–8 vs. 2). Hemiurosoma clampi nov. spec. is characterized by its vermiform body shape, colourless cortical granules distributed in irregular rows, two macronuclear nodules, three frontal cirri, one buccal cirrus, four frontoventral cirri ranged in a line, two transverse cirri, lacking postoral ventral and pretransverse ventral cirri, and marginal rows that are not posteriorly confluent. Phylogenetic analyses based on SSU rDNA gene sequences suggest that Hemiurosomoida is not monophyletic. A close relationship is revealed between Hemiurosomoida warreni nov. spec., Parakahilella macrostoma, Hemiurosoma clampi nov. spec., and the type species Hemiurosoma terricola. As expected, all these species are classified within the “non-oxytrichid Dorsomarginalia”.  相似文献   

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The morphology of a new testate amoeba Pentagonia zhangduensis nov. spec. was investigated using light and scanning electron microscopy. The new species was discovered in the sediments of Lake Zhangdu, Hubei Province, China. The low coefficients of variation and normal size frequency distribution suggest that P. zhangduensis is a size-monomorphic species. P. zhangduensis differs from the one other species in this genus (P. maroccana), by its larger size and its quadrangular cross section with two parallel longitudinal ridges on each of the two flattened sides of the test.  相似文献   

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Zingiber shuanglongensis sp.nov.is a species endemic to Taiwan,China,that has been found in Nantou and Kaohsiung.In this study,the new Zingiber species is illustrated and the results of morphological a...  相似文献   

13.
The morphology and infraciliature of two pleurostomatid ciliates, Amphileptus aeschtae nov. spec. and Amphileptus eigneri nov. spec., collected from shrimp-culturing ponds of the Bohai Sea, China, were investigated using live observations and the protargol impregnation method. The new species A. aeschtae is identified by the presence of 200-300 macronuclear nodules and several contractile vacuoles along the ventral side of the cell. A. eigneri differs from its congeners, inter alia, by the marine habitat, the presence of many contractile vacuoles along the ventral margin and the number of somatic kineties on both sides. Loxophyllum ozakii Shigematsu, 1953 is transferred to Kentrophyllum.  相似文献   

14.
Using standard methods, we describe two new Semispathidium species from semiterrestrial habitats of tropical Africa and central Europe. Semispathidium fraterculum nov. spec. and S. pulchrum nov. spec. differ from each other and from two Namibian (Southwest African) congeners by body size, the shape and location of the extrusomes; the shape of the macronucleus, the number of ciliary rows, the number of cilia within the rows, and the number of dikinetids comprising the dorsal brush rows. The globular resting cyst of S. fraterculum is unique in having countless granules on the inside of the external layer, forming sharp-angled rows. The distribution of these and two further, not yet described south African species indicates that the genus Semispathidium evolved in subtropical Africa. Semispathidium fraterculum and S. pulchrum are highly similar, both morphologically and ecologically, differing in mainly one important feature: the shape and location of the extrusomes used for prey capture. This suggests that they evolved from a common ancestor whose areal was divided by a vicariant event, causing an independent evolution of the split populations. We argue that this and other species pairs indicate that the vicariance speciation model is applicable to protists.  相似文献   

15.
The foraminiferal family Allogromiidae occurs mainly in marine environments, although some genera are described from brackish and freshwater habitats. We report here the occurrence of a terrestrial allogromiid foraminiferan. Phylogenetic relationships were investigated by sequencing part of the SSU rDNA. DNA sequence analysis confirms a close relationship of the new species to the genus Allogromia. Morphological studies corroborate the affiliation to the family Allogromiidae but the lack of an entosolenian tube and an internal septum as well as the different ecology do not allow a classification into a known genus of this family. Taking the molecular, morphological and ecological differences into account, a new genus Edaphoallogromia with the type species E. australica is erected.  相似文献   

16.
The morphology and infraciliature of two pleurostomatid ciliates, Amphileptus gui nov. spec. and A. yuianus nov. spec., collected from mariculture ponds near Qingdao (Tsingtao), China, were investigated using living observations and the protargol impregnation method. These new species are distinguished from their congeners by a combination of characters including their marine habitat and the presence of an apical group of densely packed extrusomes. Amphileptus gui nov. spec. differs from A. yuianus nov. spec. mainly in the number of contractile vacuoles (3–7 vs. 1), the shape of extrusomes (thin bar-like vs. clavate), and the number of left and right somatic kineties (7–11 and 37–50 vs. 4 and 18–22).  相似文献   

17.
The morphology and infraciliature of three pleurostomatid ciliates, Litonotus bergeri nov. spec., L. blattereri nov. spec. and L. petzi nov. spec., collected from mariculture ponds near Qingdao (Tsingtao), China, were investigated using live observations and the protargol impregnation method. These new species are distinguished from their congeners by a combination of characters including the typical distribution of extrusomes, i.e., along entire ventral margin, the number of macronuclear nodules, features and number of somatic kineties, living morphology, number and position of contractile vacuoles and their marine biotopes. Considering the distribution of extrusomes and general morphology, five new combinations are suggested, Litonotus vermiforme (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum vermiforme Sauerbrey, 1928], Litonotus levigatum (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum levigatum Sauerbrey, 1928], Litonotus undulatum (Sauerbrey, 1928) nov. comb. [basionym: Loxophyllum undulatum Sauerbrey, 1928], Loxophyllum pictus (Gruber, 1884) nov. comb. [basionym: Litonotus pictus Gruber, 1884] and Loxophyllum trichocystiferus (Foissner, 1984) nov. comb. [basionym: Litonotus trichocystiferus Foissner, 1984].  相似文献   

18.
Summary From marine mud flats a new type of photosynthetic purple bacterium was isolated. This type is described as a new species of the Rhodospirillaceae and is named Rhodopseudomonas sulfidophila. The cells are rod-shaped, 0.6 to 0.9 wide and 0.9 to 2.0 long, and motile by means of polar flagella. Cell division occurs by binary fission. The photosynthetic membrane system is of the vesicular type. The pigments consist of bacteriochlorophyll a and of carotenoids, most probably of the spheroidene group. A wide range of organic compounds can be utilized anaerobically in the light. Growth on organic compounds aerobically in the dark is also possible. Niacin, thiamin, biotin and p-aminobenzoic acid are required as growth factors. The new species needs 2.5% (w/v) sodium chloride for optimal growth. All strains show excellent photolithotrophic growth on hydrogen, hydrogen sulfide, and thiosulfate. They show a remarkably high sulfide tolerance. Sulfide and thiosulfate are oxidized to sulfate without an intermediate accumulation of elemental sulfur. The new species seems to be one of the most versatile types of photosynthetic bacteria isolated thus far.  相似文献   

19.
Summary A new species ofSaccharomyces is described, which was isolated from soils. The nameSaccharomyces smittii is proposed in memory of the late Prof.Jan Smit (Director of the Laboratory for Microbiology, Wageningen, Holland).  相似文献   

20.
A new genus of strictly anaerobic, gram-negative, banana-shaped bacteria is described. Cells formed spores and were motile by means of up to 15 laterally inserted flagella. Nitrate or sulfate were not used as electron acceptor. Organic substrates that were fermented included N-methyl compounds, such as betaine, N,N-dimethylglycine and sarcosine, primary alcohols, hydroxy fatty acids, and 2,3-butanediol. In addition, molecular hydrogen and carbon dioxide were fermented to acetate. The latter was the characteristic fermentation product in general. During growth on betaine, trimethylamine was formed in addition. The degradation of N,N-dimethylglycine yielded acetate, monomethylamine, and trimethylamine. The presence of cytochrome b and of ubiquinone in the cells was shown. The deoxyribonuleic acid base composition of the strains was between 41.3 and 47.4 mol% guanine plus cytosine. The name Sporomusa is proposed for this new genus. On the basis of the DNA-DNA homology values obtained, the shape of the spores and some other properties, the isolated strains were assigned to two species. Names proposed: Sporomusa sphaeroides and Sporomusa ovata. The type species is S. sphaeroides and the type strains are strain E, DSM 2875 (S. sphaeroides) and strain H1, DSM 2662 (S. ovata).Dedicated to Prof. H. G. Schlegel on the occasion of his 60th birthday  相似文献   

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