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1.
Aplopsora corni sp. nov. is proposed for a rust fungus whose uredinial and basidial stage occurs onCornus controversa (Cornaceae) in Hokkaido. This new species is separated by its larger urediniospores and probasidia from the morphologically closely relatedA. nyssae onNyssa aquatica andN. sylvatica (Cornaceae) distributed in southern North America.  相似文献   

2.
The structure, development, and host range of five newly detected species of the phagotrophic nanoflagellatePirsonia are described. They feed on planktic diatoms common in the North Sea:P. verrucosa sp. nov. (onRhizosolenia delicatula), P. formosa sp. nov. (onRhizosolenia setigera), P. diadema sp. nov. (onCoscinodiscus granii andC. wailesii), P. eucampiae (onEucampia zodiacus) andP. mucosa sp. nov. (onRhizosolenia shrubsolei). The occurrence of resting cysts inPirsonia guinardiae is reported. The impact ofPirsonia on phytoplankton communities is discussed.  相似文献   

3.
Polysiphonia sensu lato comprises approximately 200 species, which are currently assigned to several different genera. To date, one of these genera, namely, Polysiphonia, has been reported to have 17 species. Here, we describe for the first time P. freshwateri sp. nov. and P. koreana sp. nov. from Uljin and Ulleung Island, Korea, based on morphological and molecular evidence. Polysiphonia freshwateri sp. nov. and P. koreana sp. nov. are characterized by having the typical Polysiphonia features. Polysiphonia freshwateri sp. nov. is further characterized by having abundant trichoblasts, conspicuous scar cells, and tetrasporangia arranged in spiral series. Polysiphonia koreana sp. nov. is further characterized by having very scarce scar cells placed between two pericentral cells, from which cicatrigenous branches arise. The results of our rbcL sequence analyses support the taxonomic placement of P. freshwateri sp. nov. and P. koreana sp. nov. within Polysiphonia.  相似文献   

4.
The terrestrial diatom Microcostatus schoemanii sp. nov. is described from dry soils of the Faan Meintjies Nature Reserve (North‐West Province, South Africa). Microcostatus cholnokyi sp. nov. and Microcostatus angloensis sp. nov. are described from sandy soils at a colliery near the town of Kriel (Mpumalanga Province, South Africa). The morphology of these taxa is examined using both light and scanning electron microscopy and new taxa are compared with similar species. In M. schoemanii the density of the striae combined with the valve outline and the distance between the central raphe endings are the main distinguishing morphological features. M. cholnokyi is differentiated by the presence of a conopeum and the distinct structure of the microcostae. M. angloensis is similar to M. schoemanii but differentiated by the shape of the cell and the apices, the angle of striation and the distance in between the proximal raphe endings.  相似文献   

5.
Two new ascomycetes,Linocarpon angustatum sp. nov. andNeolinocarpon nypicola sp. nov., are described from petioles ofNypa fruticans in Malaysia.Linocarpon angustatum differs from species in the genus in having needle-shaped ascospores.Neolinocarpon nypicola differs from species in the genus in having filiform ascospores which gradually taper towards the ends, and ascomata developing within well developed stromata. These new species are compared with existing species and illustrated with interference light micrographs. The fungi known from aerial parts ofNypa fruticans are listed.  相似文献   

6.
Phylogenetic relationships among those yeast species that form saturn-shaped ascospores and which are assigned to the generaWilliopsis andPichia were estimated from their extent of nucleotide sequence divergence in three regions of ribosomal RNA. ThePichia species (P. dispora, P. saitoi, P. zaruensis andP. sp. nov.) are a closely clustered group only distantly related toWilliopsis, and it is proposed that they be reassigned toSaturnospora gen. nov. The extent of divergence amongWilliopsis species (W. californica, W. mucosa, W. pratensis, W. saturnus andW. sp. nov.) is greater than that previously observed within other ascomycetous yeast genera.  相似文献   

7.
Three new species of Candida and a new species of Trigonopsis are described based on their recognition from phylogenetic analysis of gene sequences from large subunit ribosomal RNA, ITS1/ITS2 rRNA, mitochondrial small subunit rRNA and cytochrome oxidase II. Candida infanticola sp. nov. (type strain NRRL Y-17858, CBS 7922) was isolated from the ear of an infant in Germany and is closely related to Candida sorbophila. Candida polysorbophila sp. nov. (type strain NRRL Y-27161, CBS 7317) is a member of the Zygoascus clade and was isolated in South Africa as a contaminant from an emulsion of white oil and polysorbate. Candida transvaalensis sp. nov. (type strain NRRL Y-27140, CBS 6663) was obtained from forest litter, the Transvaal, South Africa, and forms an isolated clade with Candida santjacobensis. Trigonopsis californica sp. nov. (type strain NRRL Y-27307, CBS 10351) represents a contaminant from wine in California, and forms a well-supported clade with Trigonopsis cantarellii, Trigonopsis variabilis and Trigonopsis vinaria.  相似文献   

8.
WithinFusarium sambucinum Fuckel sensu lato three species were differentiated:F. sambucinum Fuckel s. str.,F. torulosum (Berk. et Curt.) Nirenberg comb. nov. andF. venenatum Nirenberg sp. nov. They are described and illustrated in detail.  相似文献   

9.
Two new species of heliobacteria isolated from cyanobacterial mats of two alkaline sulfidic hot springs are formally described. Strains BR4 and BG29 are assigned to anoxygenic phototrophic bacteria of the familyHeliobacteriaceae, since they possess the unique properties of this taxon: strict anaerobiosis, formation of bacteriochlorophyllg, the lack of extensive intracytoplasmic membranes and chlorosomes, an unusual cell wall structure, and phylogenetic relatedness to the low G+C gram-positive eubacteria. Based on the 16S rDNA sequence similarity, strains BR4 and BG29 are assigned to the genusHeliobacterium and described as two new species of this genus:Heliobacterium sulfidophilum sp. nov. andHeliobacterium undosum sp. nov. The G+C content of the DNA is 51.3 mol % inHbt. sulfidophilum and 57.2-57.7 mol % inHbt. undosum. The cells ofHbt. sulfidophilum are rods, and the cells ofHbt. undosum are slightly twisted spirilla or short rods. Both new bacteria are motile by peritrichous flagella.Hbt. sulfidophilum produces endospores. The new bacteria are strict anaerobes growing photoheterotrophically on a limited range of organic compounds. In the dark, they can switch from photosynthesis to the slow fermentation of pyruvate. Biotin is required as a growth factor. Both species are highly tolerant to sulfide (up to 2 mM at pH 7.5) and oxidize it photoheterotrophically to elemental sulfur; photoautotrophic growth was not observed. The temperature optimal for growth ofHbt. sulfidophilum andHbt undosum is 30–35‡C, and the optimal pH is 7–8.  相似文献   

10.
The taxonomic positions of soil isolates known as Streptomyces groups A, B and C were clarified. Comparative 16S rDNA sequence studies indicated that representatives of all three taxa formed distinct phyletic lines within the Streptomyces tree though the group A strains were shown to be related to Streptomyces griseus and associated validly described species. The taxonomic integrity of all three groups was highlighted by DNA:DNA relatedness and ribotype data though the group A strains encompassed a higher degree of genetic variation than the group B and C strains. In light of these and earlier phenotypic data it is proposed that Streptomyces groups A, B and C be given species status as Streptomyces sanglieri sp. nov., Streptomyces aureus sp. nov. and Streptomyces laceyi sp. nov., respectively. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

11.
The taxonomic affiliation was determined for four Xenorhabdus strains isolated from four Steinernema hosts from different countries. As compared to the five validly described Xenorhabdus species, i.e., X. nematophila, X. japonica, X. beddingii, X. bovienii and X. poinarii, these isolates represented novel species on the basis of 16S rRNA gene sequences and riboprint patterns, as well as by physiological and metabolic properties. They were named Xenorhabdus budapestensis sp. nov., type strain DSM 16342T, isolated from Steinernema bicornutum; Xenorhabdus ehlersii sp. nov., type strain DSM 16337T, isolated from Steinernema serratum; Xenorhabdus innexi sp. nov., type strain DSM 16336T isolated from Steinernema scapterisci; and Xenorhabdus szentirmaii sp. nov., type strain DSM 16338T, isolated from Steinernema rarum.  相似文献   

12.
A novel gram-negative, thermophilic, acetate-oxidizing, sulfate-reducing bacterium, strain A8444, isolated from hot North Sea oil field water, is described. The rod-shaped cells averaged 1 μm in width and 2.5 μm in length. They were motile by means of a single polar flagellum. Growth was observed between 44 and 74°C, with an optimum at 60°C. Spores were not produced. Sulfate and sulfite were used as electron acceptors. Sulfur, thiosulfate, nitrate, fumarate, and pyruvate were not reduced. In the presence of sulfate, growth was observed with acetate, lactate, pyruvate, butyrate, succinate, malate, fumarate, valerate, caproate, heptanoate, octanoate, nonadecanoate, decanoate, tridecanoate, pentadecanoate, palmitate, heptadecanoate, stearate, and ethanol. Pyruvate, lactate, and fumarate did not support fermentative growth. Cytochromes of the c-type were present. Desulfoviridin, desulforubidin, P582, and desulfofuscidin were not present. The G+C content of the DNA was 51 mol%. Sequence analysis of 16S rDNA showed that phylogenetically strain A8444 belongs to the delta subdivision of the Proteobacteria. The closest relatives are Desulfacinum infernum and Syntrophobacter wolinii. Strain A8444 is described as the type strain of the new taxon Thermodesulforhabdus norvegicus gen. nov., sp. nov. Received: 4 May 1995 / Accepted: 11 July 1995  相似文献   

13.
Two new species of the kinorhynch genus Pycnophyes are described from the Atlantic Ocean, Northwest Spain, and the Mediterranean Sea, East of Spain, using differential interference contrast microscopy and scanning electron microscopy (SEM): Pycnophyes dolichurus sp. nov. and P. aulacodes sp. nov. Taxonomic characters from cuticular structures in homalorhagids are discussed and reevaluated. The longitudinal positions of cuticular structures along the trunk are furthermore defined, and the positional terminology is standardized. The distribution of the genus Pycnophyes in European waters is revised, revealing a poor knowledge of kinorhynch biogeography, probably due to incomplete sampling.  相似文献   

14.
15.
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   

16.
Spiny-surfaced species of Prorocentrum form harmful algal blooms, and its taxonomic identity is obscure due to the size and shape variability. Molecular phylogenies reveal two major clades: one for P. cordatum with sequences mainly retrieved as P. minimum, and the other for P. shikokuense with sequences also retrieved as P. dentatum and P. donghaiense. Several closely related clades still need to be characterized. Here, we provide nuclear SSU and LSU rRNA genes, and nuclear ITS region (ITS1-5.8S gene-ITS2) sequences of the strain CCMP3122 isolated from Florida (initially named P. donghaiense) and strains Prorocentrum sp. RCC6871–2 from the Ross Sea, Antarctica. We describe Prorocentrum thermophilum sp. nov. based on the strain CCMP3122, a species also distributed in the open waters of the Gulf of Mexico, New Zealand, and the Arabian Gulf; and Prorocentrum criophilum sp. nov. based on the strain RCC6872, which is distributed in the Antarctic Ocean and Arctic Sea. Prorocentrum thermophilum is roundish (~14 μm long, ~12 μm wide), with an inconspicuous anterior spine-like prolongation under light microscopy, valves with tiny, short knobs (5–7 per μm2), and several (<7) large trichocyst pores (~0.3 μm) in the right valve, as well as smaller pores (~0.15 μm). Prorocentrum criophilum is round in valve view (~11 μm long, 10 μm wide) and asymmetrically roundish in lateral view, the periflagellar area was not discernible under light microscopy, valves with very tiny, short knobs (6–10 per μm2), and at least 12 large pores in the right valve. Other potentially undescribed species of spiny-surfaced Prorocentrum are discussed.  相似文献   

17.
Evidence from numerical taxonomic analysis and DNA-DNA hybridization supports the proposal of new species in the genera Actinobacillus and Pasteurella. The following new species are proposed: Actinobacillus rossii sp. nov., from the vaginas of postparturient sows; Actinobacillus seminis sp. nov., nom. rev., associated with epididymitis of sheep; Pasteurella bettii sp. nov., associated with human Bartholin gland abscess and finger infections; Pasteurella lymphangitidis sp. nov. (the BLG group), which causes bovine lymphangitis; Pasteurella mairi sp. nov., which causes abortion in sows; and Pasteurella trehalosi sp. nov., formerly biovar T of Pasteurella haemolytica, which causes septicemia in older lambs.  相似文献   

18.
Two groups of previously undescribed anaerobic, gram-positive cocci recovered from human clinical infections were characterized using phenotypic and molecular genotypic methods. Comparative genotypic analysis showed that the strains within each of these two groups were homogeneous within the group and that each group was unique within the genus Peptoniphilus. The first group is most closely related to Peptoniphilus ivorii and the second group to Peptoniphilus harei. Based on these findings we propose two novel species, Peptoniphilus coxii sp. nov. and Peptoniphilus tyrrelliae sp. nov. The type strains are P. coxii sp. nov., RMA 16757T (= JCM 16892T = CCUG 59622T = ATCC BAA-2106T) and P. tyrrelliae sp. nov., RMA 19911T (= JCM 16893T = CCUG 59621T = ATCC BAA-2105T).  相似文献   

19.
Entyloma species causing white smut disease of Cosmos species have been studied. Two species can be recognized, Entyloma holwayi on C. caudatus and C. sulphureus from North America, and E. cosmi sp. nov. on C. bipinnatus from Japan and Europe.  相似文献   

20.
Novel dissimilatory perchlorate-reducing bacteria (DPRB) were isolated from enrichments conducted under conditions different from those of all previously described DPRB. Strain LT-1T was enriched using medium buffered at pH 6.6 with 2-(N-morpholino)ethanesulfonic acid (MES) and had only 95% 16S rRNA gene identity with its closest relative, Azonexus caeni. Strain MPT was enriched in the cathodic chamber of a perchlorate-reducing bioelectrical reactor (BER) and together with an additional strain, CR (99% 16S rRNA gene identity), had 97% 16S rRNA gene identity with Propionivibrio limicola. The use of perchlorate and other electron acceptors distinguished strains MPT and CR from P. limicola physiologically. Strain LT-1T had differences in electron donor utilization and optimum growth temperatures from A. caeni. Strains LT-1T and MPT are the first DPRB to be described in the Betaproteobacteria outside of the Dechloromonas and Azospira genera. On the basis of phylogenetic and physiological features, strain LT-1T represents a novel genus in the Rhodocyclaceae; strain MPT represents a novel species within the genus Propionivibrio. The names Dechlorobacter hydrogenophilus gen. nov., sp. nov and Propionivibrio militaris sp. nov. are proposed.  相似文献   

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