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XINPENG FAN MIAO MIAO KHALED A. S. AL-RASHEID WEIBO SONG 《The Journal of eukaryotic microbiology》2009,56(6):577-582
ABSTRACT. The morphology, infraciliature, and silverline system of a new marine scuticociliate, Wilbertia typica n. g., n. sp., collected from coastal waters off northern China, were investigated. The new genus Wilbertia is characterized as follows: sculptured and dorso-ventrally flattened body; dominant buccal field that is almost completely surrounded by the paroral membrane; three apically positioned long membranelles, arranged in parallel; membranelle (M)1 and M2 prominent, M3 small; reticulate silverline system. The type species W. typica n. sp. is defined by having a conspicuous anterior beak-like protrusion; five to eight caudal cilia; M1 four-rowed, M2 two-rowed; M3, single-rowed, bipartite; 15 or 16 somatic kineties; contractile vacuole positioned just posterior to the buccal field; globular macronucleus. The small subunit ribosomal DNA sequence of W. typica is 98.5% similar to the similar morphotype, Eurystomatella sinica . Phylogenetic analyses indicate that Wilbertia groups with Eurystomatella sinica forming a branch that diverges at a deep level from all other pleuronematid scuticociliates. The molecular and morphological data indicate that Wilbertia should be placed within the family Eurystomatidae, which is closely related to the well-known Cyclidiidae. 相似文献
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Wang X Schlossmacher U Wiens M Schröder HC Müller WE 《Marine biotechnology (New York, N.Y.)》2009,11(1):99-108
Polymetallic/ferromanganese nodules (Mn-nodules) have been assigned a huge economic potential since they contain considerable
concentrations of manganese, copper, nickel, iron, and cobalt. It has been assumed that they are formed by, besides hydrogenous,
nonbiogenic processes, biogenic processes based on metabolic processes driven by microorganisms. In the present study, we
applied the techniques of digital optical microscopy and high-resolution scanning electron microscopy to search for microorganisms
in Mn-nodules. They were collected from the Clarion-Clipperton Zone in the Eastern Pacific Ocean and are composed of Mn (23.9%),
Cu (0.69%), Ni (1.02%), Fe (10.9%), and Co (0.29%). These Mn-nodules, between 2.3 and 4.8 cm, show a distinct lamination;
they are composed of small-sized micronodules, 100 to 450 μm in size, which are bound together by an interstitial whitish
material. In the micronodules, a dense accumulation of microorganisms/bacteria could be visualized. Only two morphotypes exist:
(1) round-shaped cocci and (2) elongated rods. The cocci (diameter: ≈3.5 μm) are arranged in bead-like chains, while the rods
(≈2 × 0.4 μm) are arranged either as palisades or in a linear row. Energy-dispersive X-ray spectroscopy analyses showed that
the areas rich in microorganisms/bacteria are also rich in Mn, while in regions where no microorganisms are found, the element
Si is dominant. We suggest that growth of the Mn-nodules starts with the formation of “micronodules.” The formation of micronodules
is assumed to be mediated by microorganisms. After accretion of biogenic and additional nonbiogenic minerals, the micronodules
assemble to large nodules on the sea floor through additional inclusion of nonbiogenic material. 相似文献
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Sequences of the nuclear encoded small subunit (SSU) rRNA were determined for Pirsonia diadema, P. guinardiae, P. punctigerae, P. verrucosa, P. mucosa and three newly isolated strains 99-1, 99-2, 99-S. Based on phylogenetic analysis all Pirsonia strains, except P. mucosa, clustered together in one clade, most closely related to Hyphochytrium catenoides within the group of stramenopiles. However, P. mucosa was most closely related to Cercomonas sp. SIC 7235 and Heteromita globosa and belongs to the heterogenic group of Cercozoa. In addition to the SSU rDNA sequences, P. mucosa differs from the stramenopile Pirsonia species in some characteristics and was therefore redescribed in this paper as Pseudopirsonia mucosa. The three newly isolated strains 99-1, 99-2, and 99-S differed by 28 bp in their SSU rDNA sequences from their closest neighbour P. diadema and only 1 to 3 bp among themselves. These base differences and a host range similar to P. formosa were sufficient to assign them as new strains of P. formosa. 相似文献
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Fourteen species of the genus Autosticha Meyrick,1886 are recorded from Taiwan,China.The genus Cynicocrates Meyrick,1935 is proposed as a new synonym of Autosticha,and its type species A.tachytoma (Meyrick,1935) comb.nov.is transferred to Autosticha.Autosticha cordiformis sp.nov.is described as new,and A.tachytoma is redescribed with male for the first time.A checklist of all the described species in Taiwan is given.Photographs of the new species and the newly combined species are provided. 相似文献
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The population dynamics of Marginopora kudakajimensis Gudmundsson, a dinoflagellate endosymbiont-bearing soritid foraminifer, was studied in the Ryukyu Islands, the subtropical northwest Pacific. Macroalgal samples were collected monthly between November 1995 and November 1996 at a 1-m-deep lagoonal site colonized by this species. Monthly variations in the size–frequency distributions and population density indicate that this foraminiferal population replaces itself in one year. Asexual reproduction occurs twice a year, in late spring and winter; in late spring, some of the adult individuals reproduce by multiple fission simultaneously. As a result, two cohorts (a late spring and a winter cohort) are found in the population during a year. Life span of the former cohort is up to one year, while that of the latter cohort is up to six months. Megalospheric specimens comprise up to 99% of the population with a few microspheric individuals throughout the year. The life tables and survivorship curves revealed that size-specific mortality rates were very low during the first several size classes and increased thereafter, indicating low juvenile mortality with high mortality later in life. The carbonate production rate by this Marginopora population is approximately 5 kg CaCO3 m−2 yr−1, which is extremely higher than those reported for other larger foraminiferal species. 相似文献
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本文记述我国舞蛛属Alopecosa1新种:林站舞蛛A.1inzhan sp.nov.,及3新纪录种:方隔舞蛛A.akkolka Marusik,1994、客居舞蛛A.inquilina(Clerck,1757)和独行舞蛛A.solivaga(Kulczynski,1901)。新种近似于A.sokhondoensis Logunov et Marusik,1994,但新种外雌器中隔扩展部端部向前方延伸较明显,超出中隔柄部,交配管较细长,而后者外雌器中隔扩展部向前方延伸不明显,未超出中隔柄部,交配管较短;另外2者在前眼列各眼相对大小和间距方面也有差别。 相似文献
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记述新革螨属2新种:双锯新革螨Neogamasus biserrendogynii sp.nov.和双瓣新革螨Neogamasus bivalvendogynii sp.nov.。 相似文献
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记述采自浙江省的短角瘿蚊1新种:狭短角瘿蚊Anarete angusta Mo et Xu,sp.nov.. 相似文献
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Massive sedimentation of mats of the diatom Thalassiothrix longissima forming laminated diatom mat deposits (LDM) occurred intermittently in the equatorial Pacific throughout the Neogene from at least 15 to 4.8 m.y. ago. The background deposition was otherwise calcareous nannofossil diatom ooze (NO). Benthic foraminifera have been used to reconstruct the benthic environment of deposition and the role of both surface waters (as a source of food) and bottom waters (including their corrosivity) during LDM deposition. Three LDM events were studied: Site 844 (11.4 Ma, early Tortonian), Site 849 (4.8 Ma, early Zanclian and 6.6–6.8 Ma, early Messinian). A control section of NO spanning the 4.8 Ma event was studied from Site 851. In addition, the carbonate high NO immediately preceding the 4.8 Ma event was examined in Site 849. From the foraminiferal evidence it can be shown that the LDM was deposited under conditions of normal oxygenation because infaunal taxa are present throughout and there was an increase in epifaunal taxa such as Cibicides spp. However, there was a reduction in test size probably because only those smaller than 250 μm were able to move through the restricted sediment pore spaces caused by the diatom mat meshwork. The rate of accumulation of tests is highest in LDM interval and may reflect reduced predation from macrofaunal endobenthos. Among the epifaunal taxa, Nuttallides spp. show a decrease in abundance in the LDM and even immediately preceding it. This may be linked to a greater influence of corrosive AABW. Species known to feed opportunistically on phytodetritus (Epistominella exigua and Alabaminella weddellensis) are common in both NO and LDM. The increased relative abundance of A. weddellensis in the LDM may be due to this species being smaller than E. exigua and better able to exploit the food resource within the restrictive mat meshwork. The foraminiferal results corroborate the previous interpretation that preservation of lamination in the LDM is due to the physical exclusion of macro endobenthos rather than oxygen depletion of the bottom waters. 相似文献
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中国四川省妙蝇属(双翅目:蝇科)三新种 总被引:1,自引:0,他引:1
报道采自四川省西部山区蝇科中的妙蝇属Myospila Rondani,18563新种:康定妙蝇Myospila kangdingicasp.nov.,寒妙蝇Myospila frigorasp.nov.,类寒妙蝇Myospila frigoroidasp.nov.。模式标本存于中国科学院上海生命科学研究院植物生理生态研究所。 相似文献
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A new species of the genus Rhodotorula was isolated from a tubeworm (Lamellibrachia sp.) collected at a depth of 1156 m in Sagami Bay, Japan. Strain SY-89 had physiological properties quite similar to R. aurantiaca. Two phylogenetic trees, one based on internal transcribed spacer (ITS) regions and 5.8S rDNA sequences and the other based on the D1/D2 region of the large subunit (26S) rDNA sequences, united strain SY-89 to the type strain of Sakaguchia dacryoides through a considerable evolutionary distance. Strain SY-89 was differentiated from S. dacryoides by the G+C content of the nuclear DNA and differences in the ability to utilize specific carbon and nitrogen compounds. The low complementarity of strain SY-89 DNA to that of the type strain of S. dacryoides confirmed that this strain was genetically unrelated to previously known species. The tubeworm isolates are described as R. lamellibrachii sp. nov. The type strain of R. lamellibrachii is strain SY-89 (= JCM 10907). R. lamellibrachii formed a cluster with Erythrobasidium hasegawianum, R. lactosa, S. dacryoides and Sporobolomyces elongatus on the ITS and 5.8S rDNA phylogenetic tree. These five species shared a signature sequence in 26S rDNA, although this relationship was not supported by phylogeny based on the D1/D2 region of 26S rDNA. 相似文献
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本文对采自云南的铜蛛属Chalcoscirtus Bertkau,1880蜘蛛2新种Chalcoscirtus lii sp.nov.和Chalcoscirtus yinae sp.nov..做了详细的文字描述,并附有鉴别特征图和地理分布数据.模式标本保存在湖南师范大学生命科学学院. 相似文献