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1.
描述采自南澳东北部全地下沃伯顿盆地的Gidgealpa一号钻孔23号岩芯的寒武系第三统碳酸盐前缘斜坡相动物群,有11个球接子类群,包括新种Raragnostus shergoldi sp.nov.,和14个多节类三叶虫群,包括新种Dorypyge gidgealpaensis sp.nov.,Amphoton zangi sp.nov.,Solenoparia gatehousei sp.nov.和Lisania changi sp.nov.。在澳大利亚北部生物地层范围内,这一动物群隶属Undillan(Ptychagnostus punctuosus带,Doryagnostus deltoides带和Goniagnostus nathorsti带),并且可与江南斜坡带的P.punctuosus带和G.nathorsti带对比。  相似文献   

2.
描述采自南澳东北部全地下沃伯顿盆地的Gidgealpa一号钻孔23号岩芯的寒武系第三统碳酸盐前缘斜坡相动物群,有11个球接子类群,包括新种Raragnostus shergoldi sp.nov.,和14个多节类三叶虫群,包括新种Dorypyge gidgealpaensis sp.nov.,Amphoton zangi sp.nov.,Solenoparia gatehousei sp.nov.和Lisania changi sp.nov.。在澳大利亚北部生物地层范围内,这一动物群隶属Undillan(Ptychagnostus punctuosus带,Doryagnostus deltoides带和Goniagnostus nathorsti带),并且可与江南斜坡带的P.punctuosus带和G.nathorsti带对比。  相似文献   

3.
陕西南郑梁山早寒武世三叶虫   总被引:2,自引:0,他引:2  
陕西南郑梁山早寒武世三叶虫,曾经张文堂描述过两个种:Eoredlichia(Pachyredlichia)shensiensis Chang, Parabadiella huoi Chang。前者产下寒武统筇竹寺组上部,后者产中下部。本文描述的三叶虫,系产在Parabadiella huoi之下的黄绿色泥岩,是我国目前发现的最古老的三叶虫,与之共生的还有古介形虫。这些三叶虫经笔者研究计有:Parabadiella hanzhongends sp.nov., P. nanzhengensis sp. nov., P. zhongliangsiensis sp. nov., P. sp., Parabadiella (Danangouia) transversa subgen, et sp. nov., P. (Danangouia) quadrata subgen, et sp. nov., P. (Danangouia)sp.。  相似文献   

4.
广西六景剖面艾菲尔-吉维特阶界线层的腕足动物化石*   总被引:1,自引:0,他引:1  
孙元林 《古生物学报》1992,31(6):708-723
广西六景剖面民塘组底部艾菲尔-吉维特阶界线层的腕足类,是一个台地边缘相和盆地相之间过渡环境中的非近岸底栖型腕足动物群.该动物群以贝体小,属种分异度较高,缺乏明显的地方性分子为特征,石燕贝类占有明显的优势,具背中隔板类型的正形贝类发育,并有鸮头贝科的分子出现.Echinocoelia, Davidsonia 和 Pentamerella 是本腕足动物群的优势属群;其他重要分子有 Skenidioides, Vallomyonia, Leptathyris, Rhynchospirifer, Warrenella 和 Stringocephalus.文中描述腕足类17属19种,其中4新种: Vallomyonia sinensis sp. nov., Pentamerella nanningensis sp. nov., Davidsonia guangsiensis sp. nov., Echinocoelia guangsiensis sp. nov..  相似文献   

5.
贵州三都、普安早奥陶世特马豆克早期三叶虫的新材料   总被引:1,自引:1,他引:0  
本文记述新发现于贵州三都、普安下奥陶统锅塘组下部的三叶虫,计8新种,分属于7属(其中1新属),即:Hospes guizhouensis (sp. nov.), H. sanduensis (sp. nov.), Pharostomina sanduensis (sp. nov.), Protarchaeganus sanduensis (sp. nov.), Pilekia transversalis (sp. nov.), Macropyge orientalis (sp. nov.), Guotangia guotangensis (gen. et sp. nov.), Leiagnostus sanduensis(sp. nov.)。在此7属中,Hospes, Pharostomina, Protarchaeganus, Pilekia四旧属在我国是首次发  相似文献   

6.
四川西北石渠与西藏东部、青海南部相毗连,这一带大面积出露上三叠统变质碎屑岩,含双壳类Halobia cf.yunnanensis Reed,H.cf.pluriradiata Reed,H.ganziensis Chen,H.convexa Chen,H.cf.austriaca Mojsisovics等。1982年,四川区调队李庆祥等在川藏交界的金沙江东岸石渠县洛须区,该变质碎屑岩中发现一角砾岩化生物碎屑微晶灰岩体,长20余米,宽约10米,含三叶虫和牙形石。三叶虫有Mucronaspis cf.mucronata(Brongniart),Dicranopeltis cf.polytoma(Angelin),Pseudosphaerexochus(s.1.)ovalis sp nov.,Microparia(Microparia)chuanxiensis sp.nov.,Holotrachelus shiquensis sp.nov.,? Nileus luoxiensis sp.nov.,Remopleurides aff.emarginatus Toernquist,Remopleurides conicus sp.nov.,Remo-  相似文献   

7.
本文所描述的材料,系1979年9月间,南京大学地质系枣庄教学实习队,采于枣庄峰城区窝其山北坡山脊。产化石层位为中寒武统张夏组Crepicephalina带,岩性为灰色中厚层状亮晶生物屑灰岩。与其共生的三叶虫,除Crepicephalina外(图版Ⅰ,图11),还有Dorypyge,Solenoparia,Lisania,Aojia,Anomocarella等。这里所描述的三叶虫,计1新属、4新种:Zaozhuangaspis shandongensis gen.et.sp.nov.Z.similisgen.et sp.nov.,Z.pertenus gen.e sp.nov.,和Z.traperzoidalis gen.et sp.nov.。在野外工作期间,我校78级地层古生物专业方青、张建平等同学,协助采集标本,笔者在此深表感谢。  相似文献   

8.
新疆巴里坤三塘湖志留纪三叶虫   总被引:1,自引:0,他引:1  
新疆巴里坤三塘湖晚志留世阿苏山组三叶虫包括Ananaspis fecunda Barrande,Cheirurus barkolensis sp.nov.和Pacificurus sp.,与准噶尔盆地西北部乌图布拉格,哈萨克斯坦及捷克波西米亚的晚志留世三叶虫关系密切。另外对中国5个地区晚志留世三叶虫地层作了对比。Ananaspis,Pacificurus二属在中国是初次发现。  相似文献   

9.
鄂西松滋一带,三游洞群分布广泛,岩性以白云岩为主,以往除偶见叠层石外,尚未发现其它化石,岩性成为划分地层的主要根据。1980年至1981年,笔者在松滋县刘家场三游洞群上部地层中采集了较丰富的三叶虫化石,主要属种有:Saukia enshiensis Chu, Prosattkia liujiachangensis sp. nov, P. sp.。这些三叶虫的发现,证实鄂西三游洞群上部地层的地质时代为晚寒武世晚期,与华北地区上寒武统凤山阶和川东、鄂西南的毛田组可以对比,为今后鄂西上寒武统地层的进一步划分提供了重要依据。  相似文献   

10.
中国胡椒鲷属一新种   总被引:1,自引:0,他引:1  
胡椒鲷属(Plectorhynchus LacéPède)广泛分布于热带和亚热带水域,为底栖性鱼类。产我国者现有6种,其中一种经研究,认为是一新种,定名为中华胡椒鲷Plectorhynchu sinensis Zhu,Wu et Jin sp.nov.,现叙述如下。 中华胡椒鲷(新种)Plectorhynchus sinensis Zhu,Wu et Jin sp.nov.(图1)  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

17.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

18.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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