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1.
记述美盾蚧属Formosaspis 1新种:桂林美盾蚧F.guilinensis sp.nov.,模式标本采自广西桂林市七星岩的一种观赏竹(Bambus sp.)的竹杆和分枝上。其鉴别特征是中臀叶发达,突出体末端,两叶间距宽于臀叶基部宽度的1.5倍,其间有2根刚毛;第二对臀叶骨化程度低:第三臀叶可见,末端有齿列。缘管腺2-3个,背管腺特别少且小,腹管腺小而多。二龄若虫中臀叶发达,第二对臀叶顶端双分,第三臀叶缺乏。  相似文献   

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记述中国围盾蚧属Fiorinia Targioni-Tozzetti 1新种:南宁围盾蚧Fiorinia nanningensis Zhang&Feng sp.nov.。该种近似于钩樟围盾蚧F.linderaeTakagi,1969,二者臀板均无腺刺分布,并且第2臀叶退化,略突起或全无,但是可以从以下特征区别:1)新种中臀叶狭小,末端截型,内缘无锯齿(钩樟围盾蚧中臀叶大而内缘多齿);2)躯干上无腺刺或腺瘤(钩樟围盾蚧后胸有1-3个腺瘤,第1腹节有3或4个腺瘤,第2腹节有1-2个腺刺);3)无触角间突(钩樟围盾蚧触角间突小圆锥形)。对其形态特征进行了详细描述,提供了玻片绘图。研究标本保存在西北农林科技大学昆虫博物馆。  相似文献   

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将松蜕盾蚧Florinia pinicola Maskell接种于盆栽马尾松上饲养,得到大量标本,通过对这些标本的观察研究,结果发现:臀背边缘管腺的大小.数量以及触角的形态等特征变化很大;研究表明松蜕盾蚧F.pinicola、日本蜕盾蚧F.japonica、柏蜕盾蜕F.externa和霜蜕盾蚧F.prulnosa,实际上是同一个种,即松蜕盾蚧F.pinicola。  相似文献   

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本记述采自安徽黄山寄生于竹类上的美盾蚧属一新种。模式标本保存于安徽省黄山市林业局。  相似文献   

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记述中国盾蚧科2新种:拟额瘤并盾蚧Pinnaspis pseudotuberculatua sp.nov.和云南兜盾蚧Duplachionaspis yunnanensis sp.nov.。模式标本保存在西北农林科技大学昆虫博物馆。  相似文献   

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【目的】明确橄榄片盾蚧的形态特征并编制与近似种的检索表,收集整理橄榄片盾蚧的分布范围、寄主、天敌、生物学特性、经济重要性,为该蚧虫的防控措施提供依据。【方法】通过显微特征的观察和测量进行种类鉴定,研究橄榄片盾蚧的生物学及生态学相关资料。【结果】橄榄片盾蚧雌介壳长0.77 mm左右,雌成虫体长0.55 mm左右,体紫色,臀板黄色,触角瘤小且有一个弯曲的长毛,前气门有4个盘状孔,后气门无,有3对发达的臀叶,中臀叶最大,第二臀叶和第三臀叶相似,第四臀叶呈齿状凸起,围阴腺5群。【结论】橄榄片盾蚧繁殖能力强,寄主种类多,一旦入侵到未发生区,会对当地自然生态系统造成严重的危害。加强检验检疫是防治该虫的主要措施之一,生物、化学防治是治理该虫的重要方法。  相似文献   

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曾涛 《动物分类学报》2001,26(4):528-532
记述新栎盾蚧属Neoquernaspis Howell et Takagi,1981一新种,即细管新栎盾蚧N.leptosipha sp.nov和2种中国分布新纪录种,即石柯新栎盾蚧N.beshearae Liu et Tippins,1988和尼泊尔新栎盾蚧N.nepalensis (Takagi,1977),并编制了该属中国已知种类检索表,新种模式标本和新纪录标本保存于西北农业大学昆虫博物馆。  相似文献   

8.
记述中国齿盾蚧属Odonaspis Leonardi1新种——龙岩齿盾蚧Odonaspis longyanensis Wang et Feng,sp.nov.,编制了中国齿盾蚧属分种检索表,模式标本保存于西北农林科技大学昆虫博物馆。  相似文献   

9.
本文记述了枝圆盾蚧属Diaspidiotus Cockerell一新种,危枝圆盾蚧Diaspidiotu perniciabilus sp.nov.,该属是盾蚧科Diaspididae中的一个小属。新种的模式标本保存在中国科学院动物研究所。  相似文献   

10.
记述中国片盾蚧属1新种——勐仑片盾蚧Parlatoria menglunensis,sp.nov.。模式标本保存于西北农林科技大学昆虫博物馆。  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   

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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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