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徐兆良 《植物学报(英文版)》2002,44(10):1250-1254
主要报道了产自云南昆明海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中可能为自由漂浮生长的宏观藻类化石--心型龙凤山藻(新种)(Longfengshania cordata sp. nov.)和中华豆芽藻(新属、新种)(Plantulaformis sinensis gen. et sp. nov.).这些化石的发现进一步显示了澄江生物群物种多样性,为揭示该生物群爆发性演化提供了新的证据.通过对龙凤山藻属亲缘关系的深入比较研究,进一步证明该类化石应归属宏观藻类以及它们遗传上的稳定性、演化上的保守性和环境上的适应性. 相似文献
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龙凤山藻在澄江早寒武世生物群中的发现 总被引:4,自引:0,他引:4
徐兆良 《Acta Botanica Sinica》2002,44(10):1250-1254
主要报道了产自云南昆明海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中可能为漂浮生长的宏观藻类化石-心型龙凤山藻(新种)(Longfengshania cordata sp.nov.)和中华豆芽藻(新属、新种)(lantulaformis sinensis gen.et sp.nov)。这些化石的发现进一步显示了澄江生物群种物多样性,为揭示该生物群爆发性演化提供了新的证据。通过对龙凤山藻属亲缘关系的深入比较研究,进一步证明该类化石应归属宏观藻类以及它们遗传上的稳定性、演化上的保守性和环境上的适应性。 相似文献
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云南海口早寒武世褐藻化石新知 总被引:4,自引:2,他引:2
徐兆良 《Acta Botanica Sinica》2001,43(10):1072-1076
主要报道了产自云南海口耳材村早寒武世筇竹寺组玉案山段澄江生物群中的褐藻化石-拟点叶藻(Punctariopsis latifolia gen.et sp.nov.)简单拟点叶藻(Punctariopsis simplex gen.etsp.nov.)和古德带藻(Vendotaenia cf.antiqua Gnilovskaya)3种。这些化石丰富了澄江生物群物种的多样性,为研究该群生物爆发性演化提供了新的证据。同时通过对现生褐藻和褐藻化石形态学的比较研究,表明化石属和现代属在系统演化上可能有较密切的亲缘关系,并进一步证明了澄江生物群在云南海口地区发生于一个潮间带和亚潮带的海水环境。 相似文献
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文中首次报导贵州寒武系黔东统都匀阶"清虚洞组"(或乌训组)宏观藻类,计2属2种:环圈螺旋抚仙藻Fuxianospira gyrata Chen and Zhou,1997和云南中华细丝藻Sinocylindra yunnanensis Chen and Erdtmann,1991,它们是澄江生物群最常见的两类宏观藻类具有澄江生物群宏观藻类的组合特征。"清虚洞组"位于黔东统上部,介于杷榔组和凯里组之间,该组宏观藻类的发现,为寒武纪宏观藻类演化链的完整研究提供了有价值的资料。 相似文献
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徐兆良 《植物学报(英文版)》2004,46(11):1276-1280
主要报道了采自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.).通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据.同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30 m以上的亚潮带和下潮间带的海水环境. 相似文献
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徐兆良 《Acta Botanica Sinica》2004,46(11):1276-1280
主要报道了釆自云南省昆明市海口马房村鞍山早寒武世筇竹寺组玉案山段澄江生物群中的叶状红藻-似红叶藻(新属、新种)(Paradelesseria sanguinea Xu,gen.et sp.Nov.)。通过比较形态学研究,探讨了该宏观化石藻类的分类归属与亲缘关系,进一步丰富了澄江生物群生物物种多样性的认识,并为研究早寒武世生物演化及其古环境提供了新的化石证据。同时,通过对现生红藻的比较研究,进一步证明了澄江生物群在云南海口地区发生于一个水深在30m以上的亚潮带和下潮间带的海水环境。 相似文献
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贵州下寒武统牛蹄塘组生物群由大量的海绵动物和节肢动物、软体动物、刺胞动物、腕足动物、半索动物及藻类等门类化石组成 ,其下部生物群的时代早于澄江生物群。 相似文献
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《微体古生物学报》2022,(1)
本文描述了山东省临朐县龙岗村寒武系苗岭统乌溜阶馒头组上页岩段的宏观藻类化石,计2属2种:环圈螺旋抚仙藻Fuxianospira gyrata Chen et Zhou, 1997和碎片玛拉利亚藻Morania fragmenta Walcott, 1919。这两种藻类在大小和形态上可与布尔吉斯页岩和澄江生物群中的宏观藻类相比较。本研究通过探讨藻体的长宽比,认为M.fragmenta的碎片状形态可能是藻体本身生长而成的形态,而不是其命名者所认为的碎裂而成的形态。这两个属种首次在馒头组的发现,拓展了其时空分布,为华北地区寒武纪宏观藻类研究提供了较有价值的资料。 相似文献
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XU Zhao-Liang 《植物学报(英文版)》2001,43(8):863-867
The paper deals with a new species of megaalgal fossil— Enteromophites intestinalis sp. nov. found in Chengjiang Biota in the early Cambrian. A morphological comparison of the living Enteromorpha and fossil Enteromophites indicates that there probably is a close relationship between these two genera. Based on a study on the surroundings of living Enteromorpha, Enteromophites intestinalis sp. nov. might have lived in the environment of sea or salt water. 相似文献
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Lactobacillus intestinalis (ex Hemme 1974) sp. nov., nom. rev., isolated from the intestines of mice and rats 总被引:1,自引:0,他引:1
T Fujisawa K Itoh Y Benno T Mitsuoka 《International journal of systematic bacteriology》1990,40(3):302-304
The genetic and phenotypic properties of 10 strains identified as Lactobacillus intestinalis sp. nov. were examined. These strains constitute a distinct species which can be differentiated from all of the previously described homofermentative species in the genus Lactobacillus by their carbohydrate fermentation pattern. The guanine-plus-cytosine contents of their DNAs are 33 to 35 mol%. DNAs from 10 other Lactobacillus species did not exhibit significant levels of relatedness to representative strains of the new species. The name Lactobacillus intestinalis (ex Hemme) sp. nov., nom. rev. is proposed for these isolates, and strain Th4 (= ATCC 49335 = JCM 7548) is the type strain. 相似文献
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One new genus and six new species of palaeonemerteans are described and illustrated from Hong Kong and the New Territories; these are Hubrechtella sinimarinus sp. nov. and Parahubrechtia jillae gen. et sp. nov. in the Hubrechtidae, and Callinera bergendali sp. nov., Carinina sinensis sp. nov., Tubulanus hylbomi sp. nov. and Tubulanus longivasculus sp. nov. in the Tubulanidae. These bring the known number of pa-laeonemertean species from Hong Kong to 11; a key to these species, based primarily upon features distinguishable in the living animals, is provided. 相似文献
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Among living green algae assigned to the order Chlorococcales and order Zygnematales certain species develop resistant outer organic walls and/or cysts during their life cycles; as such they have the potential to become fossils. Based on morphology, comparison between living algae and microfossil remains are made with varying degrees of confidence, and a possible evolutionary pathway for certain chlorococcalean coenobial families is suggested. Twelve genera are reviewed from earliest to latest Triassic palynological assemblages from northwestern Australia; and the following taxa are described as new: Plaesiodictyon mosellanum ssp. symmetricum ssp. nov.; Plaesiodictyon mosellanum ssp. variabile ssp. nov.; Plaesiodictyon decussatus sp. nov.; Plaesiodictyon decussatus ssp. decussatus ssp. nov.; Plaesiodictyon decussatus ssp. tetracornuta ssp. nov.; Tetraporina protrusa sp. nov.; Crucigeniella? torques sp. nov.; and Paleoraphidia akestra gen. et sp. nov. (type). Their suggested natural affinities are useful in palaeoenvironmental interpretations of mostly freshwater or low-salinity habitats. 相似文献
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范青海 《Entomologia Sinica》1997,(4)
本文报道了中国一新纪录科,即同黑螨科,描述了采自福建的二新种;李氏脊螨Annerossellaliisp.nov.和凤眼莲同黑螨Homocaliguscrassipusspnov.李氏脊螨与AnnerossellaknorriGonzalez,1978相似,区别是:1)该新种须肢附节感棒ω棒状,短于跗节;侧基毛不及须肢附节的1.5倍;后者须肢跗节感棒刚毛状,侧基毛约为跗节长度的2倍;2)新种后半体毛伸过其后方相邻毛基部,d2约为该毛到e2毛基部距离的1.5倍;后者e1毛远不达f1毛基部,d2约为该毛到e2毛基部距离的3/5;3)本新种体长不及350,后者体长在520以上。凤眼莲同黑螨与Homocaligusscapularis(Kock)相似,区别是:1)该新种腹毛3b位于基节且Ⅲ线,靠近基间板,后者的3b毛位于基节Ⅲ外缘,接近转节;2)该新种背毛e2位于d1水平前方,后者的e2毛位于d1水平后方。模式标本存放于福建农业大学植保系。李氏脊螨Annerossellaliisp.nov.种名以西南农业大学螨类学家李隆术教授的姓氏命名。 相似文献
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Blomster J Bäck S Fewer DP Kiirikki M Lehvo A Maggs CA Stanhope MJ 《American journal of botany》2002,89(11):1756-1763
"Green tides" are vast accumulations of unattached green macroalgae associated with eutrophicated marine environments. They have major ecological and economic impacts globally, so an understanding of their origin and persistence is required in order to make management decisions. Blooms predominantly consist of two common fouling genera of the Ulvales, Ulva (distromatic sheets) and Enteromorpha (monostromatic tubes). In the Baltic Sea and elsewhere green tides have increased over the last few decades. On the west coast of Finland, summer blooms consist of monostromatic sheets resembling Monostroma (Codiolales). We identified these as Enteromorpha intestinalis by comparative analyses of rDNA internal transcribed spacer 1 (ITS1), 5.8S, and ITS2 sequences, the first time monostromatic sheets have been found in the genus Enteromorpha. Ordinary attached E. intestinalis sporulated freely in culture, but the sheets reproduced only by cell regeneration into typical tubular thalli. The ITS sequences were identical to those of attached E. intestinalis populations in southwestern Finland, but differed by two substitutions from other Baltic sequences. We infer that this bloom originated from local attached populations and now reproduces clonally by fragmentation. This study provides further evidence of radical changes in gross morphology of green algae under eutrophicated conditions and the need for molecular identification. 相似文献
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Species-specific oligonucleotide probes for macroalgae: molecular discrimination of two marine fouling species of Enteromorpha (Ulvophyceae) 总被引:1,自引:0,他引:1
The green seaweeds Enteromorpha intestinalis and E. compressa are important fouling organisms commonly found in polluted and nutrient-enriched marine and brackish water habitats, where they are used in environmental monitoring. Discrimination of the two species is extremely difficult because of overlapping morphological characters. In this study a quick molecular method for species identification was developed based on the nuclear rDNA ITS2 sequence data of 54 E. intestinalis samples and 20 E. compressa samples from a wide geographical range. Oligonucleotide probes were designed for species-specific hybridization to dot-blots of the PCR-amplified ITS1, 5.8S gene and ITS2 fragment of both E. intestinalis and E. compressa. Specificity of the oligonucleotide probes was confirmed by tests with taxonomically diverse species that could morphologically be confused with E. intestinalis or E. compressa. This is the first use of species-specific probes for macroalgae. The restriction endonuclease NruI digested specifically the amplified PCR product from E. compressa into two fragments detectable on agarose gels, but no suitable restriction sites were identifiable in the PCR product of E. intestinalis. 相似文献
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Morphological and Molecular Diversity of the Neglected Genus Rhizomastix Alexeieff, 1911 (Amoebozoa: Archamoebae) with Description of Five New Species
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Eliška Zadrobílková Pavla Smejkalová Giselle Walker Ivan Čepička 《The Journal of eukaryotic microbiology》2016,63(2):181-197
The genus Rhizomastix is a poorly known group of amoeboid heterotrophic flagellates living as intestinal commensals of insects, amphibians or reptiles, and as inhabitants of organic freshwater sediments. Eleven Rhizomastix species have been described so far, but DNA sequences from only a single species have been published. Recently, phylogenetic analyses confirmed a previous hypothesis that the genus belongs to the Archamoebae; however, its exact position therein remains unclear. In this study we cultured nine strains of Rhizomastix, both endobiotic and free‐living. According to their light‐microscopic morphology and SSU rRNA and actin gene analyses, the strains represent five species, of which four are newly described here: R. bicoronata sp. nov., R. elongata sp. nov., R. vacuolata sp. nov. and R. varia sp. nov. In addition, R. tipulae sp. nov., living in the intestine of crane flies, is separated from the type species, R. gracilis. We also examined the ultrastructure of R. elongata sp. nov., which revealed that it is more complicated than the previously described R. libera. Our data show that either the endobiotic lifestyle of some Rhizomastix species has arisen independently from other endobiotic archamoebae, or the free‐living members of this genus represent a secondary switch from the endobiotic lifestyle. 相似文献
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The effects of triphenyltin chloride on respiration and photosynthesis in the green algae Enteromorpha intestinalis and Ulothrix pseudoflacca 总被引:1,自引:1,他引:0
Abstract Respiration and photosynthesis in zoospores of Enteromorpha intestinalis (L.) Link and Ulothrix pseudoflacca Wille showed greater sensitivity to inhibition by triphenyltin chloride than in vegetative tissue. Photosynthesis in zoospores and vegetative tissue of U. pseudoflacca was more resistant to triphenyltin chloride inhibition than in zoospores and vegetative tissue of E. intestinalis. Respiration in zoospores and vegetative tissue of both species was equally sensitive to triphenyltin chloride. 相似文献