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1.
本文首次记述了湖南省洞庭湖DT01剖面介形类现生种,包含3属4种,它们为比利时舍氏玻璃介(相似种)Schellencandonacf.belgica(Klie,1937)、布氏土星介Ilyocypris bradyi(Sars,1890)、土星介属(未定种)Ilyocypris sp.和豆形豆形玻璃介Fabaeformiscandona fabaeformis(Fischer,1851)。上述属种在洞庭湖区为首次报道,在湖南省亦是首次。此外,S.cf.belgica在我国还很少报道。本研究可丰富我国介形类现生种数据,同时为利用该类生物定量重建本区域全新世古气候奠定基础。  相似文献   

2.
本文首次记述了采自我国贵州省红枫湖的现生介形类5属7种,分别为:近锐豆形玻璃介Fabae formiscandona subacuta(Yang,1982)、比利时舍氏玻璃介(相似种)Schellencandona cf.belgica(Klie,1937)、亮球星介Cy-clocyprisserena(Kock,1838)、克氏丽星介Cypria kraepelini(G.W.Müller,1903)、条纹薄壳介(相似种)Dolerocypris cf.fasciata(O.F.Müller,1776)、布氏土星介Ilyocypris bradyi Sars,1890、粗糙土星介I.sale-brosa Stepanaitys,1960。这些属种在红枫湖和贵州省均系首次报道,其中S.cf.belgica在我国是首次发现,文内对F.subacuta活体特征的描述在我国尚属首次。  相似文献   

3.
本文报道了角突泥介虫(Ilyocypris angulata Sars)雄体的发现。对此雄体进行了详细的描述,论述了泥介虫属的生活方式,并讨论了介形类有三种生殖方式。  相似文献   

4.
本文首次记述了采自我国东部元荡湖的现生介形类7属9种,分别为:近球形金星介Cypris subglobosa Sowerby,1840、膨大丽神介Cypretta turgida(Sars,1896)、克氏丽星介Cypria kraepelini(G.W.Müller,1903)、无偶斗星介Cypridopsis vidua(O.F.Müller,1776)、塔尔薄丽星介Dolerocypria taalensis Tressler,1937、豆形豆形玻璃介Fabaeformiscandona fabaeformis(Fischer,1851)、弯叶豆形玻璃介F.myllaina Smith et Kamiya,2007、豆形玻璃介(未定种)Fabaeformiscandonasp.和粗糙土星介Ilyocypris salebrosa Stepanaitys,1960。这些属种在太湖流域的淀泖湖群系首次报道,其中F.myllaina和I.salebrosa均首次报道于我国东部湖区。本研究丰富了我国介形类记录,可为介形类地理区系研究提供基础资料。  相似文献   

5.
Ilyocypris是陆相介形类的一个常见属。对其壳体外层瘤状凸起分类意义的认识历来存有争议。本文在对柴达木盆地第四纪具瘤或经常具瘤的Ilyocypris分子进行研究并初步查明其瘤状装饰分类意义的基础上,将其鉴定描述为三个种:Ilyocypris gibba,I.echinata和I.salebrosa。前者个体发育中壳瘤减少直至消失的变化及其与气候环境变迁的相关性表明,I.gibba的壳瘤发育程度是表型特征,区内原定的I.biplicata和I.bradyi实为I.gibba的无瘤类型。I.echinata的壳瘤也不具备分类意义。I.salebrosa则不同,其鲜明而巨大的后背瘤足以与Ilyocypris属的其它种区别开来,是稳定的种征。  相似文献   

6.
介形类(Ostracoda)因其丰富的化石记录和广布的海陆现生代表类群,而被认为是进化生物学中研究生物多样性产生机制和演变历程的颇具潜力的重要模式生物。介形类在甲壳亚门中的谱系发生位置、起源及其内部各类群间的系统关系还存在诸多争议。基于其体制构造的形态学特征,介形类被归入甲壳亚门下的颚足纲(Maxillopoda),但来自18S rDNA序列数据分析却显示Maxillopoda不是单系群。基于化石记录和壳体形态特征,高肌虫(Bradoriida)长期以来被认为是介形类的一个祖先类群,但保存有软躯体的早寒武世化石的研究表明,Bradoriida不是介形类甚至可能也不属于甲壳类。不同的研究者所强调的壳体和肢体形态特征各异,导致介形类最大的现生类群速足目(Podocopida)的四个超科之间的关系也存在诸多推测。壳体和肢体特征在系统演化意义上的不兼容,需要分子生物学等证据的介入。分子、形态和化石证据的积累及各种信息整合是系统演化研究的必然趋势。  相似文献   

7.
甘肃玉门下沟地区早白垩世下沟组介形类   总被引:3,自引:1,他引:2  
甘肃玉门下沟地区下沟组介形类化石十分丰富,该地区下沟组介形类化石共计9属4亚属,21种,本文描述了其中4新种,即Cypridea(Cyamocypris)xiagouensissp.nov.,Cypridea(Cypridea)subunicostatasp.nov.,Stenestroemiasubpeculiarissp.nov.和Stenestroemiaxiagouensissp.nov.。该介形类化石组合尤以Cypridea最为繁盛,通过分析介形类属种的形态特征和化石组合特征并结合岩性特征,推断下沟组的地质时代为早白垩世巴列姆期;并认为下沟组为水动力较弱的淡水-微咸水河湖相沉积。  相似文献   

8.
通过对青海省循化县积石镇羊圈贡拜村-西沟中新统-上新统实测剖面中介形类动物群的研究,在其中的35个层位样品中发现含介形类化石7属32种,并建立了两个组合:(1)Candona-Candoniella组合;(2)Ilyocypris-Candoniella-Candona组合。依据介形类组合带,将咸水河组上部时代厘定为中新世中期,而临夏组时代厘定为中新世晚期-上新世早期。根据介形类动物群在剖面上的分布规律,自下而上建立5个生态组合:(1)Candona-Can-doniella生态组合;(2)Ilyocypris errabundis-Ilyocypris dunschanensis生态组合;(3)Candona-Candoniella生态组合;(4)Ilyocypris biplicata-Candoniella生态组合;(5)Candonaoppressa-Candona exti ma生态组合。通过对介形类生态组合进行详细的生态特征分析,结合磁性年代学数据,将循化盆地14.6-5Ma的古气候划分为5个阶段:(1)14.6-9.5Ma为凉干期;(2)9.5-9.38Ma为热干期;(3)9.38-6.88Ma为冷干期;(4)6.88-6.83Ma为温干期;(5)6.83-5Ma为凉干期。  相似文献   

9.
本文较为详细地介绍由Kontrovitz首先使用的介形类人工内模的铸型方法。基于某些海生或淡水现生、化石介形类Echinocythereis margaritifera,Actinocythereis thompsoni, Henryhowella florienensis 和Cytherissa lacustris内模的电子扫描显微镜观察,介绍了其中具眼窦介形类的跟窦结构及术语;报道了它的形态特点和差异;讨论了服窦形态在介形类分类、个体发育,尤其是利用它在判断生物生活水体深度的潜在意义。首次报道了淡水介形类Cytherissa lacustris内模上垂直毛细管及边缘毛细管的形态特点,这些微细结构过去也难以在电镜下清楚地观察和研究。介形类人工内模的研究,为现生或化石介形类的深入研究开辟了一条新途径。  相似文献   

10.
青海可可西里盆地是青藏高原腹地最大的沉积盆地。然而对于该盆地新生代地层的沉积时代目前仍然存在争议。可可西里盆地南侧雁石坪地区雅西措组中含丰富的介形类化石,该介形类动物群对青藏高原腹地新生代生物地层对比具有重要意义。文中通过对可可西里盆地南侧雁石坪地区通天河剖面进行系统的采样和室内分析,共获得652枚介形类壳体,共鉴定识别出14属48种,自下而上建立了2个介形类组合带,即Austrocypris cf. posticaudata-Candoniella albicans-Leucocythere tropis组合带和Ilyocypris errabundis- Darwinula stenimpudica组合带。通过与柴达木盆地、伦坡拉盆地、江汉盆地以及渤海湾沿岸等地区的介形类生物地层进行区域对比研究,推测可可西里盆地通天河剖面雅西措组的沉积时代为晚始新世—早渐新世。  相似文献   

11.
New data are provided on the ostracode fauna of the Middle Neopleistocene to Holocene of the southeastern West Siberian Plain. Several species are recorded for the first time in the West Siberian Plain: Fabaeformiscandona aff. hyalina (Brady et Robertson), F. harmsworthi Scott, F. holzkampfi Hartwig, Pseudocandona insculpta Müller, Candona weltneri Hartwig, C. inaequivalvis Sars, and C. muelleri jacutica Pietrzeniuk. New evidence is presented on the distribution of the species Pseudocandona stagnalis Sars, Eucypris pigra (Fischer), Dolerocypris fasciata Fischer, Cyclocypris ovum Müller, and C. triangula Negadaev. New species, Candona kazminae sp. nov. and Ilyocypris pustulata sp. nov., are described. The study resulted in establishing the Late Karginian ostracode association.  相似文献   

12.
Jutta Günther 《Hydrobiologia》1986,143(1):411-416
About 4000 ostracod valves have been analysed from a sediment core of a cultivated bog NW of Hamburg. The deepest deposits are sands free of subfossils, the uppermost layers consist of peat. In the sediment in between, there are three layers containing undestroyed valves. The ostracod assemblies of the older claygyttja (Late-glacial) and the two younger, fine detritus deposits (Post-glacial) are strikingly different. Cytherissa lacustris, Candona neglecta, Ilyocypris bradyi, Herpetocyrpis reptans, and two Limnocythere species were found in the Late-glacial layers. Changes in abundance of these species indicate alterations in climate, lake ground, water inflow and waterlevels. Postglacial layers are rich in Metacypris cordata valves associated with numerous Candona species, L. inopinata, Darwinula stevensi, and Cyclocypris laevis. These species are characteristic of a small lake with a large littoral zone. A similar development in ostracod assemblages is found in middle Europe by Absolon (1973), although the main Candona species is not C. neglecta but C. candida. Ostracod analysis cannot demonstrate an influence of anthropogenic impacts on ostracod successions.  相似文献   

13.
Malmqvist  Björn  Meisch  Claude  Nilsson  Anders N. 《Hydrobiologia》1997,347(1-3):159-170
In this study biogeographic patterns and habitatrelationships of freshwater Ostracoda wereinvestigated in the Canary Island archipelago. Mostdata were collected from published studies, thoughalso new data from Gran Canaria are presented. In all,22 freshwater species are presently known to theCanaries. Six species, viz. Ilyocypris bradyi,Cypris bispinosa, C. pubera, Herpetocypris chevreuxi, Heterocyprisincongruens, and Sarscypridopsis lanzarotensisare new to Gran Canaria, the first two also being newto the Canaries in general. Testing the influence ofa number of variables on faunal richness indicatedonly a weak association with island area. Distancesbetween islands also proved not significant, and sodid other properties of islands, including age,altitude and precipitation. This was in contrast to acomparison set of data comprising aquatic beetles.Like beetles, however, ostracods did not show a nestedpattern, i.e. faunas of species-poor islands were notsubsets of species-rich island faunas. By having lowendemicity (endemic species lacking in the Canaries),the ostracod fauna resembled island fern floras. Bothgroups of organisms have tiny diaspores (diameter<0.1 mm) and are extensively parthenogeneticsuggesting similar dispersal and founder mechanisms.We identified a pattern (with one exception), wherethose species with distributions extending acrossseveral islands also had wider within-islanddistributions. Many species showed affinities todifferent habitats depending on conductivity of water,altitude and habitat types: whether they werepermanent or temporary, hypogean or epigean, orcharacterized by running or stagnant waters.  相似文献   

14.
Total of 40 ostracod taxa obtained from 141 different sampling locations in Bolu were examined to determine relationships between habitat preferences of species and their ecological characteristics from June to August 2006. According to the first axis of Canonical Correspondence Analysis (CCA), 52% of the relationships between species and five most influential environmental variables with 36.2% of variances were explained. Although the first four variables, air temperature, water temperature, pH, and electrical conductivity had significant influence (P?P?=?0.47) was relatively low. Spearman correlation analyses indicated that some species had weak to strong positive correlation with electrical conductivity, whereas some others had a significant negative correlation with pH and redox potential. Only two species (Herpetocypris chevreuxi and Ilyocypris inermis) had strong correlation to the habitat type (P?Heterocypris incongruens, I. bradyi, Candona neglecta, and C. candida) had high Environmental Tolerance Index (ETI) values for at least six different environmental variables. Thus, cosmopolitans are highly adaptable within a wide range of environmental conditions and geographical distribution.  相似文献   

15.
16.
The mouthparts of five North Atlantic species of the genus Orchomene have been studied in detail. The species are: O. serrata (Boeck, 1861), O. amblyops G. O. Sars, 1890, O. crispata (Goes, 1866). O. humilis (A. Costa, 1853) and O. pectinate. G. O. Sars, 1882. The structure of the mandibular molar has been studied with the aid of the scanning electron microscope. Some features of the mouthparts, common to the species examined, are interpreted as generic criteria which should justify retaining the genus Orchomene Boeck, 1870, separated from the closely related genera OrchomeneUa G. O. Sars, 1890, and Orchomenopsis G. O. Sars. 1891.  相似文献   

17.
The effect of the variation of lipid droplet volume on individual carbon content was studied in two species of planktonic freshwater copepods, Eudiaptomus gracilis G.O. Sars and Thermocyclops oithonoides G.O. Sars. It was found, that when a multiple regression of carbon content on prosoma and lipid droplet volume instead of a simple regression of carbon content on prosoma volume was applied, the unexplainied variance of individual carbon content of Eudiaptomus gracilis could be reduced. However, the use of multiple regression on Thermocyclops oithonoides data did not lead to significantly higher coefficient of determination than was obtained by using a simple regression.  相似文献   

18.
根据SARS-CoV sars7a基因设计并化学合成部分重叠引物,经二轮PCR获得sars7a基因片段,以此片段为模板并利用一对带有Kozak序列及删除终止密码的引物进行PCR,获得产物与pEGFP-N1载体连接,使sars7a基因位于.EGFP的基因上游,得到含编码Sars7a-EGFP融合蛋白基因的哺乳动物细胞表达载体。采用细胞核转染技术将重组表达载体转染K562细胞,以流式细胞仪和共聚焦显微镜分析,可检测到EGFP的绿色荧光,表明Sars7a—EGFP得到表达,该蛋白分布于整个细胞,提示Sars7a并非膜蛋白,更可能是胞浆蛋白。此外,该蛋白的表达对K562细胞凋亡无明显影响。  相似文献   

19.
Igor Hudec 《Hydrobiologia》1983,107(1):63-69
Scapholeberis echinulata Sars is rediscribed, based on type material of Sars (S. echinulata), Daday (s. erinaceus) and the author's own samples. A differential diagnosis with Scapholeberis spinifera Nicolet and S. mucronata O. F. Müller, S. microcephala Sars, S. kingi Sars and S. aurita Fischer is given.  相似文献   

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