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1.
本文记述的化石标本是1977年采自辽西喀拉沁左翼旗(简称喀左)梅勒营子公社西湾村西公路边的一套中生代晚期的陆相砂岩、页岩,夹褐色粉砂岩,页岩和泥岩,等等。其中含有丰富的昆虫,鱼化石等。这套含昆虫化石层划归沙海组,属早白垩世。 文中仅描述4个种,有1个新属2个新种,老属种不予详细描述。化石标本保存在北京自然博物馆。  相似文献   

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记述中国陕西铜川中三叠世1新属和1新种。化石采自铜川中三叠世铜川组下段上部灰绿色泥页岩。根据脉序特征,新属、新种应归于二叠澳蝎岭科Permochoristidae,新属种的名称为Qingochorista conjunctiva gen.et sp.nov.,属于陕西昆虫群(系中三叠世陕西生物群的一个化石门类)铜川昆虫组合的新成员。时代相当于欧洲拉丁尼期(Ladinian Stagc)。  相似文献   

3.
中国陕西中三叠世中蝎蛉科三新属新种(昆虫纲,长翅目)   总被引:1,自引:1,他引:0  
记述中蝎蛉科Mesopanorpodidae 4属4种,其中包括3新属4新种:Longifurcula hejiafangensi gen.et sp.nov,Ladinochorista lata gen.et sp.nov.,Allochorista erdosensis gen.et sp.nov.,Itaphlebia tongchuanensis sp.nov..化石标本采自陕西铜川中三叠统铜川组下段上部的灰绿色泥岩和页岩.这些新属、种系陕西昆虫群铜川昆虫组合的新成员(属陕西动物群、陕西生物群的一个类别).根据前人的植物、孢子、双壳、叶肢介、介形虫、昆虫化石等的研究结果,铜川组的时代划归中三叠世,相当于欧洲中三叠世拉丁尼期(Ladinian stage).  相似文献   

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记述直脉蝎蛉科两亚属的两新种和新直脉蝎蛉科1新属、种,并讨论其分类位置.这些新属种是本区独特的地方性类群,对地层划分与对比有一定的意义.化石标本采自陕西铜川中三叠统铜川组下段上部的灰绿色泥页岩.这些新属种也是铜川昆虫组合的新成员,属陕西昆虫群(系陕西生物群的一个化石类别).根据陕西生物群的特征,其时代相当欧洲中三叠世拉丁期(Ladinian Stage).  相似文献   

5.
扁足蝇科(Platypezidae)四新属   总被引:2,自引:2,他引:0  
本文所描述的扁足蝇科4新属5新种系笔者于1984年秋采于山东省莱阳县南李格庄和团旺,莱阳组第三段。这个地区以往发现的昆虫化石较少,仅秉志(1928)描述过3属3种:Chironomaptera malanura Ping,Coptoclava lo-ngipoda Ping,Mesolygaeus laiyangensis Ping。实际上,莱阳盆地的化石昆虫群种类极其丰富,笔者已经采集到直翅目、(虫非)蠊目、同翅目、异翅目、鞘翅目、膜翅目、双翅目等类型的化石,不少于50种,其中绝大多数是新发现。现将昆虫化石点交通位置及剖面资料简介  相似文献   

6.
太原西山山西组昆虫化石新属种   总被引:1,自引:0,他引:1  
山西太原市西山山西组含煤地层的昆虫化石,首先是山西区调队肖素珍等于1981年发现。这一发现,增添了山西组的化石门类和研究内容,也为地层时代归属问题提供更多的资料。翌年春,笔者在前人工作的基础上,在该区调查队的支持下,得到肖素珍、张志存的协助,共同前往该处进行化石采集工作。在所采获的昆虫化石标本中,除老属种外,又发现一些新的类型。根据这些材料,建立1个新亚科,2个新属,3个新亚属,5个新种。  相似文献   

7.
辽西侏罗系的昆虫化石   总被引:12,自引:1,他引:11  
本文描述了辽西地区侏罗系昆虫化石20属、22种,其中10新属、17新种。分别产于阜新群、热河群和南岭群海房沟组。由于大量获得了Chironomaptera 属的标本,对特征作了补充描述。这些昆虫化石的发现和研究对解决我国陆相侏罗纪地层的划分对比具有重要意义。  相似文献   

8.
洪友崇 《昆虫学报》2007,50(3):271-280
在世界上发现的舌鞘目化石很稀少,已知仅6科、12属、26种。本文记述了中三叠世舌鞘目昆虫的3个新属种,系铜川昆虫组合的新成员(也是陕西生物群的一种类别)。根据铜川组舌鞘化石和其他昆虫以及动、植物化石的研究结果,铜川组的时代相当于欧洲中三叠世的拉丁尼期(或阶)。根据舌鞘目和其他昆虫化石的性质,作者提出冈瓦纳大陆与欧亚大陆裂离时代可能提前到中三叠世之前完成。  相似文献   

9.
1923年A.W.Grabau通过对山东省莱阳盆地莱阳组早白垩世昆虫化石的研究,命名了我国第1种鞘翅目化石昆虫(Proteroscarabaeus yeni).此后,中国昆虫化石分类学者先后发表了40余篇关于我国中生代鞘翅目化石昆虫的分类论著,共描述鉴定了182种,涉及35科,137属.这些化石分布于12个省,其中三叠纪11个种,侏罗纪68个种,白垩纪103个种.本文通过图表列举出我国已发现的中生代鞘翅目化石昆虫名录以及它们的分布和年代,总结了国内中生代甲虫化石当前的研究状况,并初步分析了研究中存在的一些问题.另外本文还介绍了国外学者对于中国古昆虫学者所建立的4个新科提出的不同意见.  相似文献   

10.
近200年来,全世界共报道半翅目蜡蝉次目化石昆虫28科、216属、400余种.本文回顾了蜡蝉次目化石昆虫的研究历史,统计了中国已报道的该类群化石种类名录,总结了蜡蝉次目化石昆虫的地质历史、地理分布和年代、以及属种组成特征,提出了该类群化石昆虫研究中有待解决的问题以及未来的研究前景.  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   

18.
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   

19.
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   

20.
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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