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101.
We investigated three rare haptorid ciliates, viz., Lagynophrya gibba Kahl (1935), Enchelys lajacola nov. spec., and Spathidium implicatum Kahl (1930), using live observation, silver impregnation, morphometry, and scanning electron microscopy. Lagynophrya gibba, which was rediscovered in peatland soil from Iceland, is referred to a new genus, Kamburophrys, and a new family, Kamburophryidae, based on a unique organelle, the brush membranoid. This structure is near the dorsal brush and composed of very narrowly spaced cilia, about 5 μm long. The genus Kamburophrys has a unique combination of features, viz., an oral cone on the oral bulge, an oblique circumoral kinety, and a subapical hump carrying the three-rowed dorsal brush and the brush membranoid. The Kamburophryidae possibly belong to the order Spathidiida. Enchelys lajacola was discovered in mud from granitic rock-pools (Lajas) in Venezuela, South America. The new species is characterized by a bottle-like shape, a macronucleus with the shape of a curved strand, a heterostichad dorsal brush, and rod-shaped toxicysts. Spathidium implicatum, which was rediscovered in an ephemeral meadow puddle near Salzburg city centre, is neotypified and referred to the genus Apertospathula because it has an open circumoral kinety. 相似文献
102.
Zhe-Xue?Quail Dan-Ning?Zeng Yi-Ping?Xiao Seong?Woon?Roh Young-Do?Nam Ho-Won?Chang Jung-Hoon?Yoon Hee-Mock?Oh Jin-Woo?BaeEmail author 《Journal of microbiology (Seoul, Korea)》2009,47(2):156-161
A bacterial strain, designated Iso4T, was isolated from the East Sea of Korea and was subjected to a poly-phasic taxonomy study including phenotypic and chemotaxonomic
characteristics as well as 16S rRNA gene sequence analysis. Cells of the strain were Gram-negative, motile, non-budding, non-stalked,
and strictly aerobic. Strain Iso4T grew optimally at 20°C in the presence of 1∼2% (w/v) NaCl and at pH 6.9∼7.6. The major respiratory quinone was Q-10 and the
major cellular fatty acids were C18:1 ω7c (53.5%), C17:1 ω5c (11.7%), C17:1 ω6c (8.1%), C16:0 (7.8%), C17:0 (4.8%), C15:0 (2.9%), and C16:1 ω5c (2.2%). The DNA G+C content of strain Iso4T was 56.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain Iso4T formed a monophyletic clade in the family Hyphomonadaceae, supported by high bootstrap value and was most closely related to the genus Hyphomonas (92∼94%), a member of marine bacteria in the family. The phenotypic, genotypic, and chemotaxonomic evidences also suggest
strain Iso4T represents a novel genus and species in the family Hyphomonadaceae, for which the name Henriciella gen. nov., sp. nov. is proposed. The type strain is Iso4T (=KCTC 12513T =DSM 19595T =JCM 15116T). 相似文献
103.
Alexandre Fedorovich Bannikov Giorgio Carnevale Walter Landini 《Comptes Rendus Palevol》2009,8(6):535-544
A new genus of sciaenid fish Caucasisciaena is erected to accommodate the Early Miocene eastern Paratethys species Perca ignota Smirnov, 1936, which, subsequently, was variously attributed to the modern genera, either Larimus or Otolithoides. The materials examined include 32 specimens from four Caucasian and Crimean localities of Sakaraulian age (Lower Burdigalian). The new genus is based on a unique combination of features, including: parasphenoid with a dorsal rounded bony flange; basisphenoid present; premaxilla with short ascending process forming obtuse angle with alveolar process and ascending/alveolar process ratio about 0.17; anterior premaxillary teeth enlarged; posttemporal with few robust spines along its posterior margin; presence of 25 vertebrae; presence of three tiny supraneurals; dorsal fin with 11 spines plus 22–24 soft rays; anal fin with two spines and 7–8 soft rays; second anal-fin spine long and massive; pectoral fin elongate; scales ctenoid on body and cycloid on head (except for one or two rows of ctenoid scales on the cheek). Paleoecological considerations suggest that Caucasisciaena probably was a predatory fish that inhabited the coastal waters of the eastern sector of the Paratethyan basin. 相似文献
104.
105.
A new genus and species of “libellulid” dragonfly, Austrolibellula noroestenia nov. gen., nov. sp., of the group Italoansida BECHLY, 1996, is described. The specimen comes from the Maíz Gordo Formation (late Paleocene) that crops out in northwestern Argentina. Its phylogenetic relationships within Cavilabiata BECHLY, 1996 are discussed. 相似文献
106.
Gorlenko V. M. Bryantseva I. A. Panteleeva E. E. Tourova T. P. Kolganova T. V. Makhneva Z. K. Moskalenko A. A. 《Microbiology》2004,73(1):66-73
A new nonmotile purple sulfur bacterium (strain M9) was isolated from the steppe soda lake Lake Dzun Uldziin Nur (pH 9.4; mineralization, 3.3%) situated in southeastern Mongolia. Individual cells appear as vibrios 0.3–0.5 × 0.7–1 m in size. The dividing cells often do not separate from each other, forming an almost closed ring. The internal photosynthetic membranes are represented by concentric lamellae lining the cell wall. Photosynthetic pigments are bacteriochlorophyll a and carotenoids of the spirilloxanthin series. The main carotenoid (>96%) is spirilloxanthin. Two typical light-harvesting complexes (LH1 and LH2) are present in the membranes in a 1 : 1 ratio. The bacterium is an anaerobe and facultative photoorganoheterotroph. Photolithoautotrophic growth on sulfide is scarce. Thiosulfate is utilized as an electron donor only in the presence of organic matter. Globules of elemental sulfur are formed as an intermediary product of sulfide and thiosulfate oxidation and are deposited outside the cells. The end product of oxidation is sulfate. In the presence of sulfide and carbonates, acetate, lactate, malate, pyruvate, propionate, succinate, and fumarate are used as additional sources of carbon in anoxygenic photosynthesis. Vitamins are not required. The bacterium is an alkaliphile, the pH optimum is at 8.3–9.1, the pH range is 7.6–10.1. The optimum NaCl concentration in the medium is 1 to 7%; the range is 0.5 to 0.9%. The optimum carbonate content in the medium is 2%; the range is 1 to 10%. The best growth occurs at 30–35°C. The DNA G+C content is 57.5 mol %. According to the results of analysis of the 16S rRNA gene sequences, the new isolate M9 belongs to the phylogenetic cluster containing representatives of the family Ectothiorhodospiraceae within the class Gammaproteobacteria. In this class, the new isolate forms a new branch, which occupies an intermediate position between the representatives of the genera Ectothiorhodospira and Thiorhodospira. Based on the phenotypic and genetic characteristics, the new purple sulfur bacterium was assigned to a new species of a new genus of the family Ectothiorhodospiraceae, Ectothiorhodosinus mongolicum gen. nov., sp. nov. 相似文献
107.
Enigmagraptus n. gen. comprises a group of the smallest known graptolites, with problematical evolutionary ancestors. The species described,
all of Přídolí age are:E. yassensis (Rickards &Wright, 1999),E. cf.yassensis, E. mitchelli (Rickards &Wright, 1999) andE. pennyae n. sp.
相似文献
108.
Francischetti IM Mather TN Ribeiro JM 《Biochemical and biophysical research communications》2003,305(4):869-875
109.
MICHAEL J. MELCHIN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1999,32(4):261-269
Isolated specimens of Hercograptus introversus n. gen., n. sp. show features characteristic of the Retiolitidae, such as partial periderm reduction, and extended ancora lists and a reticulum that are attached to the thecal margins, on a rhabdosome that, in most other respects, resembles Pseudorthograptus. This newly discovered graptolite provides support for the hypothesis that Pseudoretiolites is the first-evolved retiolitid, since they share a similar ancora type and unique thecal style. It is also clear that the suite of features that normally distinguish the Retiolitidae did not all evolve simultaneously. It is proposed that development of a complete thecal framework of lists, permitting complete periderm reduction, should be the character used to distinguish the Retiolidae from the Petalolithidae. Unusual apertural modifications, such as strong introversion, lateral lappets, and a short, free dorsal wall suggest that Hercograptus may be an offshoot of the lineage leading from Pseudorthograptus to Pseudoretiolites. 相似文献
110.
A new sand‐dwelling dinoflagellate from Palau, Galeidinium rugatum Tamura et Horiguchi gen. et sp. nov., is described. The life cycle of this new alga consists of a dominant nonmotile phase and a brief motile phase. The motile cell transforms itself directly into the nonmotile cell after swimming for a short period, and cell division takes place in the nonmotile phase. The nonmotile cell possesses a dome‐like cell covering, which is wrinkled and equipped with a transverse groove on the surface. The cell has 10–20 chloroplasts and a distinct eyespot. The motile cell is Gymnodinium‐like in shape. The dinoflagellate possesses an endosymbiotic alga to which the chloroplasts belong and which is separated from the host (dinoflagellate) cytoplasm by a unit membrane. The endosymbiont cytoplasm also possesses its own eukaryotic nucleus and mitochondria. The eyespot is surrounded by triple membranes and is located in the host cytoplasm. Photosynthetic pigment analysis, using HPLC, revealed that G. rugatum possesses fucoxanthin as the principal accessory pigment instead of peridinin. The rbcL tree showed that G. rugatum is monophyletic with Durinskia baltica (Levander) Carty et Cox and Kryptoperidinium foliaceum (Stein) Lindemann and that this clade is closely related to the pennate diatom, Cylindrotheca sp. The endosymbiont of G. rugatum is therefore shown to be a diatom. Phylogenetic analysis based on small subunit rDNA sequences demonstrated that G. rugatum, D. baltica, and K. foliaceum, all of which are known to harbor an endosymbiont of diatom origin, are closely related. 相似文献