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1.
From the Buschmann-Klippe-Formation, mainly considered as Late Precambrian in age until now, the ArchaeocyathaBuschmannia roeringi, n. gen., n. sp. is described. Based on this discovery, an Early Cambrian age for the Nama-group is assumed.  相似文献   

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From the Autunian of the Saar-Nahe-BasinAcanthodes tholeyi n. sp., a new species of acanthodians is described. Only the holotype (part and counterpart) is known. It differs from the well knownAcanthodes bronni in several characteristics like the anatomy of the pectoral fin, length-/width rate of the pectoral fin spine, length/width of the unpaired ventral spine and the existence of a ventral fin, supported by ceratotrichia.  相似文献   

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WithAcanthodes bourbonensis n.sp. another acanthodian from Lower Permian basins of Europe is described. The new species is similar toAcanthodes gracilis (Beyrich) from Silesia (Poland), but it differs from this and all other species of the genus in the development of the pectoral fins, dorsal fin, anal fin and caudal fin. In pectoral fins, dorsal and anal fin there are different ceratotrichia as supporting elements and pectoral fins are attaching along a row of oblonged large scales. In the caudal fin there is an epichoral appendix first found byHeyler (1969).  相似文献   

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The laminated sediments of the Lower Oligocene ‘Sieblos-Schichten’ (dysodile and kieselgur-sediments) contain many individuals of a naviculoid diatom species. Formerly this group of diatoms would have been classified without doubt as Navicula (section ‘Minusculae’). After splitting this extremely heterogeneous genus in Navicula sensu stricto and some other homogeneous genera, the pattern of structures of this fossil species does not correspond to any established genus. For that reason this form will be described as the generotype of a new genus Eolimna. Furthermore it became evident that some Recent species (assigned to Navicula) show the same pattern of structures as the new genus Eolimna (generotype: E. martinii) which represents one of the first naviculoid diatoms of limnic origin. The essential criteria of this genus are: comparatively small cells with narrow girdle; simple alveolated rib system; areolae with a hymen in approximately medium position between relatively large sized foramina outside and inside of the valve; a single row of more or less irregular arranged areolae in close position to each other, on one or several of the copulae. The differences to supposed related genera are discussed.  相似文献   

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A taxonomic study was conducted on 16 bacterial strains isolated from wild Adélie penguins (Pygoscelis adeliae) from Seymour (Marambio) Island and James Ross Island. An initial screening by repetitive sequence-based PCR fingerprinting divided the strains studied into four coherent groups. Phylogenetic analysis based on 16S rRNA gene sequences assigned all groups to the genus Corynebacterium and showed that Corynebacterium glyciniphilum and Corynebacterium terpenotabidum were the closest species with 16S rRNA gene sequence similarities between 95.4 % and 96.5 %. Further examination of the strains studied with ribotyping, MALDI-TOF mass spectrometry, comprehensive biotyping and calculation of average nucleotide identity and digital DNA–DNA hybridisation values confirmed the separation of the four groups from each other and from the other Corynebacterium species. Chemotaxonomically, the four strains P5828T, P5850T, P6136T, P7210T representing the studied groups were characterised by C16:0 and C18:1 ω9c as the major fatty acids, by the presence of meso-diaminopimelic acid in the peptidoglycan, the presence of corynemycolic acids and a quinone system with the predominant menaquinone MK-9(H2). The results of this study show that the strains studied represent four new species of the genus Corynebacterium, for which the names Corynebacterium antarcticum sp. nov. (type strain P5850T = CCM 8835T = LMG 30620T), Corynebacterium marambiense sp. nov. (type strain P5828T = CCM 8864T = LMG 31626T), Corynebacterium meridianum sp. nov. (type strain P6136T = CCM 8863T = LMG 31628T) and Corynebacterium pygosceleis sp. nov. (type strain P7210T = CCM 8836T = LMG 30621T) are proposed.  相似文献   

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A completely perichondrally ossified endocranium of a generalized reprsentative of the Eubrachythoraci,Beyrichosteus radiatus n. g., n. sp., is described. The specimen shows a typical platybasie skull with widely separated nasal capsules like that of the mainly Early Devonian Dolichothoraci. This is contrary to the spezialized generaTapinosteus andPholidosteus from Wildungen, being previously often regarded as model for the endocranium of coccosteomorph arthrodires. However, characters of the orbit and the nasal capsule are more similar to other Eubrachythoraci than to those of Dolichothoraci and primitive Brachythoraci. Until now, there are not enough other examples of sufficiently preserved endocrania of brachythoracid arthrodires known for a phylogenetic analysis. Nevertheless, the observations made onBeyrichosteus are questioning the assignment of the Pholidosteidae to the Coccosteomorphi.  相似文献   

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Two isolates, AC04T and AC05, were isolated from the flowers of red ginger collected in Chiang Mai, Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates were included within a lineage comprised of the genera Acidomonas, Gluconacetobacter, Asaia, Kozakia, Swaminathania, Neoasaia, Granulibacter, and Tanticharoenia, and they formed an independent cluster along with the type strain of Tanticharoenia sakaeratensis. The calculated pair-wise sequence similarities of isolate AC04T were 97.8–92.5% to the type strains of the type species of the 11 genera of acetic acid bacteria. The DNA base composition was 66.0–66.1 mol % G+C with a range of 0.1 mol %. A single-stranded, labeled DNA from isolate AC04T presented levels of DNA-DNA hybridization of 100, 85, 4, and 3% respectively to DNAs from isolates AC04T and AC05 and the type strains of Tanticharoenia sakaeratensis and Gluconacetobacter liquefaciens. The two isolates were unique morphologically in polar flagellation and physiologically in intense acetate oxidation to carbon dioxide and water and weak lactate oxidation. The intensity in acetate oxidation almost equaled that of the type strain of Acetobacter aceti. The two isolates had Q-10. Isolate AC04T was discriminated from the type strains of the type species of the 11 genera by 16S rRNA gene restriction analysis using restriction endonucleases TaqI and Hin6I. The unique phylogenetic, genetic, morphological, physiological, and biochemical characteristics obtained indicate that the two isolates can be classified into a separate genus, and Ameyamaea chiangmaiensis gen. nov., sp. nov. is proposed. The type strain is isolate AC04T (=BCC 15744T, =NBRC 103196T), which has a DNA G+C content of 66.0 mol %.  相似文献   

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A mass occurrence of peculiar centric diatoms was found in a freshwater diatomite included in Miocene deposits of the Rhoen mountains in Central Germany. Similar forms were determined asMelosira jouseana in the literature. However, detailed observations in the LM and SEM exhibit morphologic characteristics which are completely unknown inMelosira and inAulacoseira. Regular triangulate and trilobate outlines of the valve faces occur and dominate besides circular ones. Variable support partitions and pillars are inserted between discus and Ringleiste. Such stabilizing elements are lacking in all comparable recent and known fossil genera. Instead of the extensive cingulum inAulacoseira the cells possess only a single copula which encloses the very short collum. A structure (l“fringe-curtain“) starting from the distal margin of this copula covers like a grid the mantle of the associated valve. Sulcus and pseudosulcus do not occur and rimoportulae or fultoportulae were not observed. Therefore a new genus is introduced with a new species,Miosira rhoenana. Miosira jouseana in the new combination is based onMelosira jouseana Moiseeva 1971.  相似文献   

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Euzkadiella erenoensis n. gen. n. sp. from the Early Cretaceous of Ereño (Prov. Guipuzcoa, northern Spain) is the first known »stromatoporoid« with a spicular skeleton and a basal skeleton consisting of calcific spherulites. The stromatoporoid sponge shows subtylostyle, oxea and strongyle megascleres. Microscleres are unknown. The sclere arrangement appears as disorganized bundles connected by horizontal sclere bridges. This sclere arrangement is characteristic of the order Haplosclerida (Class Demospongiae, Subclass Ceractinomorpha). The new species is compared with the modern coralline spongesCalcifibrospongia andAstrosclera, and with the Mesozoic stromatoporoids of the families Milleporellidae and Actinostromariidae. In both subclasses of the Demospongiae and within the Class Calcarea stromatoporoid basal skeletons are observed. Therefore the subclass Stromatoporoidea does not exist as a true systematic unit.  相似文献   

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A novel alkalophilic salt-tolerant rod-shaped bacterium, designated ANESC-ST, was isolated from an extremely alkali–saline soil in the rural area of Anda city in northeast China. Taxonomic study using a polyphasic approach revealed that this non-motile, orange colony-forming microbe was Gram-negative and obligately aerobic. Optimal growth of strain ANESC-ST was achieved in the presence of NaCl with a concentration range of 0.5 to 4 % and pH between 7.5 and 9.2, and at temperatures ranging from 10 to 37 °C. Phylogenetic analysis of 16S rRNA sequences showed that of strain ANESC-ST is most homologous to Mongoliicoccus roseus MIM28T and Litoribacter ruber YIM CH208T with sequence similarity of 95.1 and 93.2 %, respectively. The genomic DNA G+C content of strain ANESC-ST was determined to be 39.1 mol%. The main isoprenoid quinone in ANESC-ST was found to be menaquinone-7. The main fatty acids were found to be iso-C15:0 (27.5 %), iso-C17:03-OH (14.0 %), anteiso-C15:0 (9.8 %), summed feature 9 (iso-C17:1ω9c and/or 10-methyl C16:0 10.6 %) and summed feature 3 (C16:1w7c/C16:1w6c, 9.78 %). Based on the phenotypic, chemotaxonomic and phylogenetic data, strain ANESC-ST is considered to represent a new genus and species classified into the order Cytophagales, for which the name Anditalea andensis gen. nov., sp. nov. is proposed. The type strain is ANESC-ST (=CICC 10485T = NCCB 100412T).  相似文献   

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