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从形态学而论,烟杆藓属(Buxbaumia Hedw.)在苔藓植物中是一个独特的类型。该文简要介绍了烟杆藓属的历史和该属在中国的研究状况,以及该属的模式种烟杆藓首次在中国的发现。对烟杆藓在新疆的着生生境及群落状况做了详细介绍, 还就扫描电子显微镜观察烟杆藓的孢蒴、蒴齿和孢子形态、中国烟杆藓属分种检索表及属的系统关系进行观察和探讨。  相似文献   

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Andrés Boltovskoy 《Grana》2013,52(2-3):98-107
Glochidiniumgen. nov., a ncw genus of Peridiniaceae based on Peridinium penardiforme Lindemann, is herewith erected. Its plate formula is: Po+X+4′+6′′+3C+4S+5′′′+2′′′′ Main diagnostic characters of this new genus are the presence of only 3 cingular plates (it lacks the transitionalone), the third cingular contacting the anterior sulcal plate, and an unusual sulcus holding a small triangular posterior sulcal plate. The thecal morphology and structure of two freshwater planktic species of the genus are described on the basis of LM and SEM observations. G. penardiforme comb. nov. is an infrequent species, albeit widely distributed world-wide. It has been recorded under the names of Peridinium, Glenodinium and Peridiniopsis. Peculiar features in the tabulation of the furrows and of the surface sculpture show that the species does not fit any of the known genera, for which reason the new genus Glochidinium is established. G. platygaster sp. nov., the second species included in the genus, differs from the former by its elongated body, the regular pentagonal shape of its large first apical plate, an equally large sulcal anterior plate, and well developed sculpture, chiefly on the antapical plates. Glochidinium penardiforme and G. platygaster were found in some reservoirs from central and northern Argentina. G. penardiforme was also found in several Argentine rivers and ponds.  相似文献   

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The genus Panax (Araliaceae) is world-famous because many its members have important medicinal properties. Panax ginseng C. A. Meyer is more popular than other species of the genus because remedies prepared from this plant stimulate immunity, help to prevent diseases, and have antistress effects. In addition, the ginseng root extract is traditionally used as a means against aging. At present, this species is found in the wild only in Primorsky krai, Russia, but its populations are extremely exhausted and need to be restored. In this study, effectiveness of molecular DNA markers in detecting genetic variation and differentiation of the ginseng populations was tested. Genetic variation of ginseng, identified using RAPD (P = 4%; H pop = 0.0130) and ISSR (P = 9.3%; H pop = 0.0139) markers was low. The AFLP* approach, according to which amplicons are separated in polyacrylamide gel and visualized by means of silver staining, showed somewhat higher variability (P = 21.8%; H pop = 0.0509), while its effectiveness in population differentiation was as low as that of RAPD and ISSR. The AFLP** technique, which included analysis of the fragments using genetic analyzer, revealed high genetic diversity of ginseng (P = 94.4%; H pop = 0.3246). All populations examined using the AFLP** markers were statistically significantly differentiated based on the AMOVA results. Our result suggest effectiveness of AFLP** markers for characterization of the genetic structure and genetic relationships of the ginseng populations. These markers are recommended for use in large-scale population genetic studies of this species to develop measures of its conservation.  相似文献   

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A Gram-negative, aerobic, rod shaped, non-spore-forming bacterial strain, designated Dae08T, was isolated from sediment of the stream near Daechung dam in South Korea, and was characterized in order to determine its taxonomic position, using a polyphasic approach. Comparative 16S rRNA gene sequence analysis showed that strain Dae08T belongs to the family Xanthomonadaceae of the Gammaproteobacteria, and is related to Lysobacter brunescens ATCC 29482T (97.3%). The phylogenetic distances from any other species with validly published names within the genus Lysobacter were greater than 3.7%. The G+C contents of the genomic DNA of strain Dae08T was 69.3 mol%. The detection of a quinone system with Q-8 as the predominant compound and a fatty acid profile with iso-C15:0, iso-C17:1, ω9c, iso-C17:0, iso-C16:0, and iso-C11:0 3-OH as the major acids supported the affiliation of strain Dae08T to the genus Lysobacter. DNA-DNA relatedness between strain Dae08T and its phylogenetically closest neighbour was 28%. On the basis of its phenotypic properties and phylogenetic distinctiveness, strain Dae08T (= KCTC 12600T) should be classified in the genus Lysobacter as the novel species, for which the name Lysobacter daecheongensis sp. nov. is proposed.  相似文献   

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Desulfovibrio strain JJ isolated from estuarine sediment differed from all other described Desulfovibrio species by the ability to degrade fructose. The oxidation was incomplete, leading to acetate production. Fructose, malate and fumarate were fermented mainly to succinate and acetate in the absence of an external electron acceptor. The pH and temperature optima for growth were 7.0 and 35° C respectively. Strain JJ was motile by means of a single polar flagellum. The DNA base composition was 64.13% G+C. Cytochrome c 3 and desulfoviridin were present. These characteristics established the isolate as a new species of the genus Desulfovibrio, and the name Desulfovibrio fructosovorans is proposed.  相似文献   

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A polyphasic taxonomic approach was used to characterize a Gram-negative, non-motile bacterium, designated MJ15T, that was isolated from soil of a GS-Caltex Oil reservoir in Korea. As shown by comparative 16S rRNA gene sequence analysis, strain MJ15T belongs to genus Brevundimonas. The 16S rRNA gene sequence similarities ranged from 95.6–99.2% between strain MJ15T and validated representatives of the genus Brevundimonas. With respect to Brevundimonas species, strain MJ15T exhibited DNA-DNA relatedness values below 40.7%. The G+C content of the genomic DNA was 61.7 mol%. Strain MJ15T contained ubiquinone Q-10. The major fatty acids were C16:0 (27.7%), C19:0 cyclo ω8c (23.2%), summed feature 8 (containing C18:1 ω7c/C18:1 6c) (28.5%), and major hydroxyl fatty acid was C12:0 3OH (3.7%). Based upon its phenotypic and genotypic properties, as well as its phylogenetic distinctiveness, strain MJ15T (KCTC 22461T; JCM 16237T) should be classified in the genus Brevundimonas as the type strain of a novel species. The name Brevundimonas olei sp. nov. is proposed for this new species.  相似文献   

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A new lepocreadiid genus, Amphicreadium, is erected for the species A. denspeniculus n. sp. from Acanthaluteres vittiger and for an unnamed species from Meuschenia freycineti, both from off northern Tasmania. The new genus is distinguished from all other members of its family by its amphistomatous body plan.  相似文献   

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Summary The operculate genus Chytridium Braun is emended and restricted to approximately 25 known species and several incompletely known members which lack an apophysis and develop much like species of Rhizophydium, insofar as the zoosporangium and absorbing or rhizoidal system are concerned, and form endobiotic or intramatrical resting spores. This interpretation corresponds fairly closely to Braun's diagnosis of the type species.A new genus, Diplochytridium, is established to segregate the former Chytridium species with an endobiotic or intramatrical apophysis or prosporangium and resting spores, which may develop sexually or asexually. Some of these species have a well-defined endo-exogenous alternation of growth and development in which the apophysis appears to function as a prosporangium. As interpreted here, Diplochytridium includes approximately 20 of the known species.Another new genus, Canteria, is created for a parasite of Mougeotia which Canter first described as a species of Phlyctidium but later found to develop endobiotic resting spores or zygospores by the fusion of conjugation tubes.  相似文献   

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The genus Obelus, so far known from shells only, is re-described on the basis of the anatomy of its genital system. Its range is here restricted to north-western Africa and the Canary Islands. Four species are traditionally listed for the Canary Islands: Obelus despreauxii, O. moderatus, O. mirandae and O. cyclodon. The presence of the last species on the Canary Islands is doubtful, whereas the fossil/subfossil presence of O. pumilio is documented. The species Helix morata also belongs to the genus, as well as a new species, O. discogranulatus sp. nov. The genital systems of all confirmed extant Canarian species are shown. Obelus has a peculiar vaginal stimulator appendix (“appendicula”) which is homologous to the penial appendix of the Orthurethra and to the stimulatory organ of other Stylommatophora, with the exception that the A3 portion is missing. The genus is diagnosed by characters of the vaginal stimulator appendix, such as a curved, finger-like A2 portion of the appendicula ending proximally in a blind, well-developed muscular sac, and by the slender tubular A4 portion arising laterally from the muscular sac duct. We conclude that Obelus belongs to the Cochlicella group because it shares an appendicula with the other genera of the group. However, it differs in anatomical details of this structure. The Cochlicella group should be recognized as a separate family Cochlicellidae Schileyko, 1972, with close relationships to the Helicellidae and the Hygromiidae. A new diagnosis for Cochlicellidae is proposed and its phylogenetic relationships are discussed.This is: Notes on the Malacofauna of the Canary Islands, No. 46.  相似文献   

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The genus Dendromyza (Amphorogynaceae) comprises approximately 21 species with a distribution from the Malay Archipelago to southern Australia. Two new hemiparasitic species in this genus: D. hiepkoana from Irian Jaya and D. staufferi from Papua New Guinea are here described, illustrated and compared. Dendromyza hiepkoiana is similar to members of the genus Phacellaria (Benth.) where the leaves are very small and bract‐like, but differs in its separate stigmas and chambered fruits that possess a crown of fibers on the endocarp. Dendromyza staufferi is allied to D. reinwardtiana (Bl. ex Korth.) Danser but differs from this species by broader, ovate rather than narrower, spathulate leaves and sessile inflorescences. Dendromyza staufferi also has an ovoid rather than elliptical endocarp and the crown of fibres at the apex of the endocarp are pilose. Due to their hemiparasitic nature and aerial habitat, species of Dendromyza are generally considered to be vulnerable in terms of conservation status. Based on the information available to us, however, the species described here are categorised as locally common or near threatened.  相似文献   

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A new type of gas-vacuolated, sulfate-reducing bacterium was isolated at 10° C from reduced mud (E0 < 0) obtained from a temperate estuary with thiosulfate and lactate as substrates. The strain was moderately psychrophilic with optimum growth at 18–19° C and a maximum growth temperature of 24° C. Propionate, lactate, and alcohols served as electron donors and carbon sources. The organism grew heterotrophically only with hydrogen as electron donor. Propionate and lactate were incompletely oxidized to acetate; traces of lactate were fermented to propionate, CO2, and possibly acetate in the presence of sulfate. Pyruvate was utilized both with and without an electron acceptor present. The strain did not contain desulfoviridin. The G+C content was 48.4 mol%. The differences in the 16S rRNA sequence of the isolate compared with that of its closest phylogenetic neighbors, bacteria of the genus Desulfobulbus, support the assignment of the isolate to a new genus. The isolate is described as the type strain of the new species and genus, Desulforhopalus vacuolatus. Received: 4 March 1996 / Accepted: 17 June 1996  相似文献   

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Recent studies showed that a group of Hypertelis species was neither related to the type of that genus or to other members of Molluginaceae. As a result, these species were segregated as a new genus in its own family, Kewaceae. The St Helenan endemic Kewa acida (Hook.) Christenh. is illustrated here and its relationships, status, cultivation and conservation are discussed.  相似文献   

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Six species of the genus Thermocyclops have hitherto been known from Chinese freshwaters. A new species is here recorded from a sample collected from an eutrophic pool in central China. It is described and compared using classical morphology and mapping of its pore signature. Thermocyclops dumonti differs from T. kawamurai by absence of ornamentation on prominences of intercoxal plates of P1‐P3, by relative length of apical spines of Enp3P4 and caudal ramus. It differs from T. dybowskii by ornamentation of P4 intercoxal plate, relative length of Enp3P4 and caudal ramus, by shape of Tmi. As in other species of Thermocyclops, the perforations are bilaterally symmetrical and, species‐specific patterns occur on the cephalosome, metasome, and urosome. Conserved patterns are found elsewhere on the rostrum, cephalosome, metasome, and furcal branches. Based on pore pattern, Thermocyclops dumonti is separated from two close relatives, T. schmeili and T. dybowskii.  相似文献   

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A new species of halophilic anoxygenic purple bacteria of the genus Rhodospirillum is described. The new organism, isolated from water/sediment of the Dead Sea, was vibrio-shaped and an obligate halophile. Growth was best at 12% NaCl, with only weak growth occurring at 6% or 21% NaCl. Growth occurred at Mg2+ concentrations up to 1 M but optimal growth was obtained at 0.05–0.1 M Mg2+. Bromide was well tolerated as an alternative anion to chloride. The new organism is an obligate phototroph, growing photoheterotrophically in media containing yeast extract and acetate or a few other organic compounds. Growth of the Dead Sea Rhodospirillum species under optimal culture conditions was slow (minimum td 20 h). Cells contained bacteriochlorophyll a and carotenoids of the spirilloxanthin series and mass cultures were pink in color. Absorption spectra revealed the presence of a B875 (light-harvesting I) but no B800/B850 (light-harvesting II) photopigment complex. The new organism shares a number of properties with the previously described halophilic phototrophic bacterium Rhodospirillum salinarum and was shown to be related to this phototroph by 16S rRNA sequencing. However, because of its salinity requirements, photosynthetic properties, and isolation from the Dead Sea, the new phototroph is proposed as a new species of the genus Rhodospirillum, R. sodomense.  相似文献   

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A Gram-positive, aerobic, non-motile bacterium designated F3-P9T, was isolated from dye waste water in Korea and was characterized using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain F3-P9T belongs to genus Leucobacter. The 16S rRNA gene sequence similarities among strain F3-P9T and validated representatives of the genus Leucobacter ranged from 95.9–97.4%. Strain F3-P9T exhibited DNA-DNA relatedness values below 48% with respect to Leucobacter species. The G+C content of the genomic DNA was 67.5 mol%. F3-P9T contained MK-11 as the major respiratory quinone. The major fatty acids were anteiso-C15:0 (48.5%), anteiso-C17:0 (22.7%), and iso-C16:0 (14.5%). The peptidoglycan was composed of L-2,4-diaminbutyric acid, alanine, glycine, and glutamic acid. The polar lipid profile showed a major amount of diphosphatidylglycerol (DPG), a moderate amount of phosphatidylglycerol (PG), and two unknown glycolipids. On the basis of its phenotypic and genotypic properties and its phylogenetic distinctiveness, strain F3-P9T (KEMC 211-128T =KACC 16572T =JCM 17539T) should be classified in the genus Leucobacter as the type strain of a novel species, for which the name Leucobacter kyeonggiensis sp. nov. is proposed.  相似文献   

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A new species of Manihot was discovered in the course of revising the taxonomy of some species of the genus occurring in the Midwest Region of Brazil. Its morphology resembles species which belong to different sections of the genus. However, a set of characters related to stem, leaves, inflorescences and flowers serves to differentiate it from the closest species, especially from M. falcata, to which it is most similar. The geographical distribution and conservation status of the new species as well as its flowering and fruiting period are also provided. Additionally, anatomical information about the aerial parts of the stem, a novelty regarding the wild species of the genus, is provided.  相似文献   

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