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1.
简述早寒武世关山动物群的研究现状及重要意义。重点描述该动物群中一三叶形虫新属PanlongiaLiuetLuogen.nov.及其两个新种:即个体小、拥有等大的头甲和尾甲、边缘没有明显突出刺状物的PanlongiatetranodusaLiuetLuogen.etsp.nov.及头甲后侧和尾缘具刺的PanlongiaspinosaLiuetLuogen.etsp.nov.。三叶形虫在关山动物群中的首次发现为寒武纪生命大爆发以及古地理、古板块恢复的研究提供了有益的证据。  相似文献   

2.
J.-C. Klein 《Plant Ecology》1972,25(1):311-333
Sans résuméJe tiens à remercier M. le Dr. J. Braun-Blanquet de la généreuse hospitalité qu'il m'a offerte à la S.I.G.M.A. et des précieux conseils qu'il m'a dispensés pour la définition de ces associations. C'est la raison pour laquelle il m'a paru nécessaire de l'associer à l'une des Associations originales que j'ai décrites.Je suis également reconnaissant à mes amis M. et G. Roux d'avoir permis le traitement de mes données floristiques par l'analyse factorielle des correspondances.  相似文献   

3.
J. -C. Klein 《Plant Ecology》1972,25(5-6):311-333
Sans résuméJe tiens à remercier M. le Dr.J. Braun-Blanquet de la généreuse hospitalité qu'il m'a offerte à la S.I.G.M.A. et des précieux conseils qu'il m'a dispensés pour la définition de ces associations. C'est la raison pour laquelle il m'a paru nécessaire de l'associer à l'une des Associations originales que j'ai décrites.Je suis également reconnaissant à mes amisM. et G. Roux d'avoir permis le traitement de mes données floristiques par l'analyse factorielle des correspondances.  相似文献   

4.
MaTePHa几oM八月只HaeTo兄以e盆CTaTbHCo6PaHHa只aBToPoMBnoe几y水H几a 60刀b山a月Ko月几eK以H月enHPH中ePH几,C“Hb双sRH KHP. BPaxHono几曰rg,7 ro八y Ha eeBePHoM eK加He xPe6Ta BoPoxoPo npoB“HuHH6仪几”eo6PaH汉xz3丁eMHo一eeP卜Ix丁oHKo3epxlHeT曰x H3BeeTI王只KoB万让1水IJerO116占生物学报7卷RaP6oHa,eo八eP水a以“x由几b比oe Ko几H叨eTBo Pyro3,RoToP曰e 6H几H onPe双e刀eH从T.A.八o6P邸旧6oBo直”H.B.Ka6aKoBHq.Pyro3H nPe八CTaB几eH曰:c侈。inia ex.gr.s夕umo,aGorsky,Ca刀i牡i“…  相似文献   

5.
J. -C. Klein 《Plant Ecology》1972,24(4-6):311-333
Résumé Au cours d’investigations phytosociologiques que nous avons menées sur l’étage montagnard des massifs du Nord de la Corse, nous nous sommes particuli?rement int?ress? aux groupements des “pentes écorchées” (J. Briquet 1901), représentés par des garrigues á xérophytes épineux. Ces formations, qui avaient fait l’objet d’une étude préalable de R. de Litardiére (1926 et 1928), nous ont permis d’aboutir á la d?finition phytosociologique de deux associations nouvelles. Ce travail a ?té entrepris sur les versants Sud du massif du Cinto, dans le Niolo et la vallée supérieure du Tavignano, autour du lac de Nino. Je tiens á remercier M. le Dr. J. Braun-Blanquet de la généreuse hospitalité qu’il m’a offerte á,la S.I.G.M.A. et des précieux conScils qu’il m’a dispensés pour la définition de ces associations. C’est la raison pour laquelle il m’a paru nécessaire de l’associer á l’une des Associations originales que j’ai décrites. Je suis également reconnaissant á mes amis M. et G. Roux d’avoir permis le traitement de mes données floristiques par l’analyse factorielle des correspondances.  相似文献   

6.
Sagittopteris  belemnopteroides gen.et sp.nov.在山西的发现   总被引:1,自引:1,他引:0  
山西晚古生代植物自赫勒(Halle,1927)研究以来向为世人瞩目。解放后,李星学(1963)又对华北广大地区月门沟群的化石进行了详细研究,补充了前人的不足。近年来,山西省区域地质调查队在1/20万区域地质调查和一系列的专题研究中,采集了大量化石标本。笔者在鉴定中发现不少有意义的分子,本文报道的即系其中之一。化石为作者之一肖素珍于1976年在晋东南参加剖面测制时采集的。本种在山西其他地区亦有出现。如太原西山、沁水杏峪、柳林、沁  相似文献   

7.
描述了贵州水城大河边煤矿晚二叠世龙潭组的植物茎干化石Guizhouoxylon dahebianense gen. et sp. nov., 茎具清楚生长轮,髓部较大,初生木质部内始式,原生木质部由环纹管胞、稀螺纹管胞组成,后生木质部包括有密螺纹管胞和密螺纹至梯纹增厚的导管组成,导管近端部的穿孔板椭圆形,梯纹至网纹增厚。次生木质部密材型,射线单列,一般低矮,管胞自内向外由梯状纹孔变为不规则拥挤分布的具缘纹孔,偶而可见木薄壁细胞。根据后生木质部中导管的穿孔板类型与低等被子植物Platanus acerifolia Willd相似,也讨论了被子植物的起源问题。  相似文献   

8.
Rossmania ukurunduensis gen. and sp. nov. collected in the reverve Bolshekhekhtsirsky (Khabarovsk Territory, Russian Far East) is described and illustrated.Rossmania aculeata comb. Nov. is indicated as the second species of the genus.  相似文献   

9.
1957年春,地质陈列馆胡承志、牛业华在云南路南老第三系地层中采集了一批哺乳类化石,其中的一部分标本已经研究发表(周,1958)。在这篇报告中,我们又描述了一个完整的雷兽类的头骨,代表一个新的渐新世种。此外,尚有一些未经描述的材料,也将陆续予以描述发表。路南老第三系地层,经过对最近采集的一些哺乳类化石的研究,表明这是到目前为止,代表华南地区最完整的一个老第三系剖面,包括从上始新统至上渐新统间的全套地层,和几个不同时代的脊推动物化石层。进一步的地层调查和化石的系统采集,将对华南老第三系地层的了解和区域对比提供重要的基本研究资料。  相似文献   

10.
11.
1957年,苏联科学院动物研究所的考察队在黄海工作时,我们曾经对寄生於海产鱼类的单殖亚綱动物区系作了研究。在所发现的大量种类之中,有一种按其形态学的特徵是如此的特殊,不仅足以划分为单独的一属,而且无疑地还是一个新科的代表。在考虑到这一个种的重要意义时,我们认为提出其初步的描述是适当的。关於这一种的较详细的报导,要在作者把所收集的,不仅包括成体的,而且还有它们胚胎期后各发育阶段的全部资料加以详细的研究后,才能完成。  相似文献   

12.
Ougandatherium napakense nov. gen. nov. sp., the earliest Rhinocerotidae Iranotheriinae from Africa. The Uganda Palaeontology Expedition discovered an exceptionally rich fossiliferous channel deposit at Napak I, Karamoja, in 1999, which yielded two partial skeletons of a new genus and species of early Miocene Rhinocerotidae, together with various other mammals and gastropods typical of Faunal Set I of East Africa. The age of the deposits on the basis of both faunal correlation (biochronology) and radio-isotopic dating is ca 19–20 Ma. The new genus and species is a hornless rhinoceros about the size of a small horse, with long slender limb bones and metapodials and hypsodont upper cheek teeth whose enamel is undulate, and fossettes cement-filled. Upper premolars possess an inner wall; this is clearly an iranotheriine morphology. As such it is the earliest known African member of this subfamily, close to the oldest member of the subfamily recently discovered at Bugti in Pakistan, a site whose age is about the same.  相似文献   

13.
Isolates AH11T and AH13T were isolated from flowers of lantana and candle bush respectively collected in Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of Saccharibacter floricola. The calculated pair-wise 16S rRNA gene sequence similarities of isolate AH11T were 95.7–92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. The DNA base composition was from 51.2 to 56.8 mol % G+C, with a range of 5.6 mol %. When isolate AH11T was labeled, DNA-DNA similarities were 100, 12, 4, 5, and 4% respectively to isolates AH11T and AH13T and the type strains of Saccharibacter floricola, Gluconobacter oxydans, and Acetobacter aceti. The two isolates were non-motile and did not oxidize either acetate or lactate. No growth was found in the presence of 0.35% acetic acid w/v. The two isolates were not osmophilic but osmotolerant, produced 2,5-diketo-D-gluconate from D-glucose, and did not oxidize lactate, thus differing from strains of Saccharibacter floricola, which showed weak lactate oxidation. The two isolates contained unsaturated C18:1ω7c fatty acid as the major fatty acid, and were unique in the presence of a considerable amount of straight-chain C18:12OH fatty acid. Q-10 was present as the major isoprenoid quinone. Neokomagataea gen. nov. was proposed with the two species, Neokomagataea thailandica sp. nov. for isolate AH11T (=BCC 25710 T =NBRC 106555T), which has 56.8 mol % G+C, and Neokomagataea tanensis sp. nov. for isolate AH13T (=BCC 25711T=NBRC 106556T), which has 51.2 mol % G+C.  相似文献   

14.
An obligately anaerobic sporeforming bacterium assigned to a new genus and species Anaerobacter polyendosporus gen. et spec. nov. is described. Characteristic features distinguishing the bacterium from known anaerobic sporeformers were variable cell shape, including spherical, the ability to form up to five endospores per cell, diffusive distribution of reserve polysaccharide throughout the cytoplasm, independence from growth factors. The eubacterial nature of the organism was revealed by its sensitivity to 1 mg/l of streptomycin, rifampicin, penicillin and to lysozyme. It belonged to Firmicutes by the type of cell wall structure. The cell wall consisted of one layer; the outer membrane was absent. The cells were not motile. The spores were spherical or oval, heat-resistant, contained dipicolinic acid and had typical endospore structure. Cortex, coats, spore coare, and in most cases exosporium could be distinguished. The bacterium fermented carbohydrates, but not amino acids. The products of fermentation included ethanol, acetate, lactate, butyrate, butanol, H2 and CO2. Sulfate or nitrate could not be used as electron acceptors, but nitrite was reduced to NH 4 + in a dissimilatory process. The bacterium was capable of fixing N2. The G + C content of the DNA was 29 mol %. The bacterium was isolated from meadow-gley soil.  相似文献   

15.
Isolates AH11(T) and AH13(T) were isolated from flowers of lantana and candle bush respectively collected in Thailand. In phylogenetic trees based on 16S rRNA gene sequences, the two isolates formed an independent cluster, which was then connected to the type strain of Saccharibacter floricola. The calculated pair-wise 16S rRNA gene sequence similarities of isolate AH11(T) were 95.7-92.3% to the type strains of the type species of the 12 genera of acetic acid bacteria. The DNA base composition was from 51.2 to 56.8 mol % G+C, with a range of 5.6 mol %. When isolate AH11(T) was labeled, DNA-DNA similarities were 100, 12, 4, 5, and 4% respectively to isolates AH11(T) and AH13(T) and the type strains of Saccharibacter floricola, Gluconobacter oxydans, and Acetobacter aceti. The two isolates were non-motile and did not oxidize either acetate or lactate. No growth was found in the presence of 0.35% acetic acid w/v. The two isolates were not osmophilic but osmotolerant, produced 2,5-diketo-D-gluconate from D-glucose, and did not oxidize lactate, thus differing from strains of Saccharibacter floricola, which showed weak lactate oxidation. The two isolates contained unsaturated C(18:1)ω7c fatty acid as the major fatty acid, and were unique in the presence of a considerable amount of straight-chain C(18:1)2OH fatty acid. Q-10 was present as the major isoprenoid quinone. Neokomagataea gen. nov. was proposed with the two species, Neokomagataea thailandica sp. nov. for isolate AH11(T) (=BCC 25710(T)=NBRC 106555(T)), which has 56.8 mol % G+C, and Neokomagataea tanensis sp. nov. for isolate AH13(T) (=BCC 25711(T)=NBRC 106556(T)), which has 51.2 mol % G+C.  相似文献   

16.
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   

17.
依据一近完整的相关节的骨骼化石,记述了辽宁建昌早白垩世九佛堂组原始今鸟类一新属种:小齿建昌鸟(Jianchangornis microdonta gen.et sp.nov.)。新鸟个体较大,但从骨化程度分析,正型标本可能属于一亚成年个体。具有一些进步特征,如胸骨及龙骨突加长,乌喙骨具有发育的前乌喙突以及和肩胛骨关联的关节窝,叉骨"U"字型,愈合荐椎包括9-10枚荐椎,尾综骨短小,第二、三掌骨远端愈合,跗跖骨完全愈合等,表明新属无疑属于今鸟类。在以下特征组合上很容易和已知的早白垩世今鸟类化石相区别:齿骨上至少有16枚细小牙齿,从齿骨前端向后沿齿骨大部密集排列;肩胛骨强烈弯曲;第一掌骨粗壮,较其他掌骨宽;第一指长并且远端延伸明显超过第二掌骨;肱骨+尺骨+第二掌骨与股骨+胫跗骨+跗跖骨的长度比例约为1.1。系统发育分析表明新属属于基干的今鸟类。新发现的材料第二、三掌骨远端愈合很好,但近端却未完全愈合,这一特征尚未见于其他已知鸟类,或许表明今鸟类腕掌骨的愈合和现生鸟类的跗跖骨一样是从远端开始的,不同于反鸟类和其他基干鸟类。建昌鸟的下颌还保存了一个前齿骨,这是继早白垩世红山鸟之后的另一例报道,可能进一步表明这一结构在今鸟类中曾普遍出现。新鸟肩带、胸骨和前肢的特征显示了和现代鸟类相近的飞行能力,其后肢、脚趾的比例以及趾爪的形态等显示和燕鸟、义县鸟等相似的地栖特征。保存于标本上的鱼类残骸可能显示了建昌鸟食鱼类的习性。今鸟类新属种的发现进一步表明,早白垩世这一进步鸟类类群的分化已不亚于反鸟类,湖滨环境在今鸟类的早期演化中确实扮演了重要的角色。  相似文献   

18.
19.
A new monothalamous (single-chambered) soft-walled foraminiferal species, Arnoldiellina fluorescens gen. et sp. nov., was isolated from samples collected in the Gulf of Eilat, Israel. The species is characterized by a small elongate organic theca with a single aperture of allogromiids. It is characterized by the emission of green autofluorescence (GAF) that has so far not been reported from foraminifera. Phylogenetic analysis of a fragment of the 18S rDNA indicates that the species is related to a group of monothalamous foraminiferans classified as clade I. Although the morphology of the new species is very different compared to the other members of this clade, a specific helix in 18S rRNA secondary structure strongly supports this position.  相似文献   

20.
《中国古生代植物》首次将Gigantopteris这一属名限定在一些具重网状叶脉的大羽羊齿类植物,如真正的G.nicotmnaetblia等,而叶脉简单结网的一些植物则大多被归入Gigantonoclea属。这一比较简便的做法近年也开始受到质疑。Gigantopteris fukienensis Yabe et Oishi,1938也是因为叶脉简单结网而被改归于Gigantopteris属内。问题在于G.fukienensis的脉式与华北典型的Gigantonoclea迥异,它的三级脉以合轴二歧式一等二歧式分叉,细脉彼此间只是偶尔联结,而主要是借助与缝脉相交形成伸长形的网眼。加之,网眼内不具点痕,而每一网眼内有1—2个点痕则是华北典型Gigantonoclea的特征之一。根据叶脉特征,作者为一些三级脉以等二歧式一合轴二歧式分叉、细脉仅偶尔相互联结而主要借助与相邻脉束或缝脉相交而形成网眼、网眼内不具点痕的一些相关植物建立了新属Fujmnopteris gen.nov.,并对此属的4个种(包括1新种)作了种的特征描述和有关的讨论和比较。  相似文献   

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