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31.
Generic characteristics and phylogenetic relationships of the genus Cyphononyx are presented, together with a brief review of the biology of the genus. It is shown that only one species of the genus, C. fulvognathus (Rohwer), occurs in Japan. This species is distributed also in Taiwan and south China, and has hitherto been recognized under the name of C. dorsalis. In addition, two new combinations are presented: Cyphononyx hirtus (Haupt, 1935) (= Cryptochilus hirtus Haupt) and Cyphononyx plebejus (de Saussure, 1867) (= Agenia plebeja de Saussure), both of which were recorded from the Oriental Region. 相似文献
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Molecular characterization of microbial communities in deep coal seam groundwater of northern Japan 总被引:2,自引:0,他引:2
We investigated microbial methanogenesis and community structure based on 16S rRNA gene sequences from a coal seam aquifer located 843–907 m below ground level in northern Japan; additionally, we studied the δ13C and δ2H (δD) of coal‐bed gases and other physicochemical parameters. Although isotopic analysis suggested a thermocatalytic origin for the gases, the microbial activity and community structure strongly implied the existence of methanogenic microbial communities in situ. Methane was generated in the enrichment cultures of the hydrogenotrophic and methylotrophic microorganisms obtained from coal seam groundwater. Methanogen clones dominated the archaeal 16S rRNA gene libraries and were mostly related to the hydrogenotrophic genus Methanoculleus and the methylotrophic genus Methanolobus. Bacterial 16S rRNA gene libraries were dominated by the clones related to the genera Acetobacterium and Syntrophus which have a symbiotic association with methanogens. LIBSHUFF analysis revealed that N2 gas injected into the coal seam (for enhanced methane production) does not affect the coverage of archaeal and bacterial populations. However, amova analysis does provide evidence for a change in the genetic diversity of archaeal populations that are dominated by methanogens. Therefore, N2 injection into the coal seam might affect the cycling of matter by methanogens in situ. 相似文献
33.
AKIRA SHIMIZU MARIUS WASBAUER YASUOKI TAKAMI 《Zoological Journal of the Linnean Society》2010,160(1):88-117
The Pompilidae (spider hunting wasps) show a marked diversity in their hunting and reproductive ecology, but difficulties in phylogenetic taxonomy have hindered the elucidation of their evolutionary processes. We present here a review of the hunting and reproductive ecology of the pepsine tribe Ageniellini (including the first prey record for Macromerella), and phylogenetic analyses of this group to reconstruct the evolution of nest‐constructing behaviour. The maximum parsimony and Bayesian inference analyses are based on 45 adult morphological characters, coded for 41 exemplar species, including five out‐group species, representing almost all the genera and subgenera in this tribe. Results supported the following eight clades uniting more than one genus: (1) Cyphononyx + Cryptocheilus + Ageniellini; (2) Ageniellini; (3) Auplopodina, containing Dimorphagenia, Auplopus, Machaerothrix, Phanagenia, Dichragenia, Paragenia, Macromerella, and Macromeris; (4) Phanagenia + Dichragenia + Auplopus artemis + Paragenia + Macromerella + Macromeris; (5) Auplopus artemis + Paragenia + Macromerella + Macromeris; (6) Paragenia + Macromerella + Macromeris; (7) Macromerella + Macromeris; and (8) Ageniella (Lissagenia) + Phanochilus. The monophyly of the genera Auplopus and Ageniella s.l. was not confirmed. The evolution of nesting behaviour was inferred, as burrowing in the soil without using water was ancestral in Ageniellini, and constructing nests by plastering mud obtained by softening soil with water was derived only once at the ancestor of the Auplopodina. The origin of cleptoparasitism was unclear. The origin of communal nesting is also discussed in relation to the evolution of nest‐constructing behaviour. The following new combinations are proposed: Ageniella (Alasagenia) sartoriana (Cresson) comb. nov. , Cyemagenia certator (Nurse) comb. nov. , and Auplopus artemis (Bingham) comb. nov. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 160 , 88–117. 相似文献
34.
AKIRA P. TAKAGI SATOSHI ISHIKAWA THUOK NAO SRUN LIM SONG SITHA HORT KHAMPHAY THAMMAVONG BOUNTHONG SAPHAKDY AKHANE PHOMSOUVANHM MUTSUMI NISHIDA HISASHI KUROKURA 《Biological journal of the Linnean Society. Linnean Society of London》2010,101(3):575-582
Mitochondrial DNA analysis was used to investigate genetic variation in the bronze featherback fish Notopterus notopterus in Indochina. Five hundred and five fish samples collected from 11 localities were separated into three genetically differentiated intraspecific groups. Chao Phraya River samples formed a distinct group. Mekong River samples were clearly separated into two different groups, namely, middle and lower Mekong groups. The lower Mekong group was closely related to Malay Peninsula group, even though the two groups are separated by a tract of ocean. F‐values (0.82–0.95) also confirmed genetic differentiation of the middle and lower Mekong groups. Although the two Mekong groups inhabit the same river basin, molecular clock calculations indicate they separated approximately 1.2 Mya, suggesting (1) evolutionary divergence before invasion of the Mekong River; (2) differences in migration routes to the river; and/or (3) differences in the timings of invasion. The complexities of historical events cannot be ignored in determinations of factors responsible for the exceptional biodiversity in the Mekong basin. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 575–582. 相似文献
35.
Primary leaves of intact bean plants (Phaseolus vulgaris L.) were treated with benzyladenine (BA) at different stages during growth. Changes in DNase, RNase, and proteas activities in the leaves were followed. Unlike the case of various excised tissues, cytokinin raised the activities of these hydrolases in intact bean leaves. Because BA elevated the levels of DNA, RNA, and protein in intact leaves, it may stimulate both synthesis and decomposition of these cellular constituents. The hydrolase activities showed differential responses to BA according to the age at which the leaf received the hormone treatment. 相似文献
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MAKIKO NAGAI MIWA OHNISHI TAKEO UEHARA MUTSUMI YAMAGAMI EIKO MIURA MAI KAMAKURA AKIRA KITAMURA SHU‐ICHI SAKAGUCHI WATARU SAKAMOTO TERUO SHIMMEN HIDEHIRO FUKAKI ROBERT J. REID TETSURO MIMURA 《Plant, cell & environment》2013,36(10):1826-1837
The concentration of ions in plant cells and tissues is an essential factor in determining physiological function. In the present study, we established that concentration gradients of mobile ions exist in both xylem exudates and tissues within a barley (Hordeum vulgare) primary leaf. For K+ and NO3?, ion concentrations generally decreased from the leaf base to the tip in both xylem exudates and tissues. Ion gradients were also found for Pi and Cl? in the xylem. The hydathode strongly absorbed Pi and re‐translocated it to the rest of the plant, whereas Cl? was extruded. The ion concentration gradients developed early during leaf growth, increased as the tissue aged and remained under both high and low transpiration conditions. Measurement of the expression profiles of Pi, K+ and NO3? transporters along the longitudinal axis of the leaf revealed that some transporters are more expressed at the hydathode, but for most transporters, there was no significant variation along the leaf. The mechanisms by which longitudinal ion gradients develop in leaves and their physiological functions are discussed. 相似文献
40.
内蒙古松树山的植物区系与沙地油松林群落特征 总被引:1,自引:0,他引:1
根据多次对内蒙古松树山地区的植物调查资料和沙地油松林群落学的研究,结果表明:(1) 松树山在植物区系上,正处在蒙古植物区系、华北植物区系、长白植物区系和达乌里植物区系的交汇地区。植物种类比较丰富,种子植物达394种。松树山植物的科、属、种分别占科尔沁沙地的61.1%、58.1%和41.1%;(2) 松树山植物区系地理成分以温带性质成分占绝对优势,占本地区的90.61%,其中以温带亚洲成分、旧世界温带成分和中国-日本成分最多,分别占本地区的16.8%、14.0%和13.7%;(3) 沙地油松林是松树山地区和科尔沁沙地唯一的针阔叶混交林类型,群落生活型谱以地面芽植物种类最丰富,占40.7%,其次为高位芽植物(22.2%)和地下芽植物(25.5%)。(4) 沙地油松林可划分为沙地胡枝子蒙古栎油松林和沙地山杏油松林2个类型,前者主要分布在石质沙丘上,后者多分布在固定沙丘的阴坡。群落演替进程为沙地先锋植物群落阶段→根茎禾草杂类草群落阶段→沙地灌丛群落阶段→沙地油松林阶段。 相似文献