鱼类寄生六鞭毛虫五新种

六鞭毛科(Hexamitidae)属动鞭纲(Zoomastigophorea)、双体目(Diplomonadida).自Moore首次报道寄生于鱼类的六鞭毛虫始,到目前为止,已报道寄生于鱼类的六鞭毛虫,共计30余种,分别隶属于六鞭毛虫属(Hexamit a)和旋核鞭毛虫属(Spironucleus).作者发现五新种,它们是寄生于细鳞斜颌鲴(Xenocypris microlepis Bleeker)的关桥六鞭毛虫(Hexamit a guanqiaoensis sp. nov.)、寄生于黄尾鲴(Xenocypris dividi Bleeker)的梁子湖六鞭毛虫(Hexamita liangzihuensis sp. nov.)和微小旋核鞭毛虫(Spironucleus mi nutus sp. nov.)、寄生于银鲴(Xenocypris argentea Günther)的多形六鞭毛虫(He xamita varformis sp. nov.)和粒状旋核鞭毛虫(Spironucleus granularis sp. nov.).采用蛋白银染色方法,对寄生于鱼类的六鞭毛虫进行了研究.       

中国鲴亚科鱼类同工酶和骨骼特征及系统演化的探讨：鲤形目：鲤科

本文对鲴亚科Xenocyprinae共4属6种鱼和鲢亚科Hypophthal michthyinae的鲢、鳙Aristichihys nobilis进行了骨骼系统的研究,并对鲴亚科的6种鱼同工酶谱型,进行了分析比较。鲢亚科虽然具有鲴亚科的共同祖征和全部离征,但因其有较多的特化性状,仍将其列为和鲴亚科并列的一个亚科。应用分支系统学原理推导出鲴亚科的系统发育图。鲴亚科6种鱼的肝、肾、心、眼的晶状体、鳍、脑,肌肉等7种组织5种同工酶(LDH,MDH,ES,ADH,G6PDH)的电泳分析表明,生化分类和经典分类结果完全一致。     

鲤科鲴亚科鱼类的系统发育及动物地理学

以雅罗鱼亚科为外群,采用分支系统学的原理和方法对鲐亚科17个属(须鳊属除外)进行了系统发育和动物地理学的分析。结果表明,(1)鲴亚科这17个属为一个单系群,并由4个较小的单系群组成;(2)鲴亚科现在的地理分布格局除源自离散事件外,主要源于扩散事件。鲐亚科的特征演化还表明,东亚地区地质历史的反转演化和平行演化可能在鲴亚科系统发育过程中起了重要的作用。     

指环虫属的早期辐射及其与宿主鲤科鱼类的协同进化关系

本研究利用28SrDNAC1-D2区序列分析采自鲤科鱼类中6亚科宿主和寄生在花鲈、梅花鲈上的共17种指环虫的系统发育关系。同时,通过比较宿主鲤科鱼类与指环虫的系统发育树,检验指环虫与其宿主是否存在协同进化关系。结果表明:17种指环虫形成5个进化支(Clade),其中寄生在团头鲂(亚科)和鲢、鳙(鲢亚科)上的6种指环虫聚为一支(Clade1),而它们的宿主鱼类在系统发育分析中也表现为近缘关系;寄生在鲮鱼(野鲮亚科)上的D.quanfami(Clade5)位于系统树最基部,鲫鱼和鲤鱼(鲤亚科)的寄生指环虫处在系统树的次基部位置,而鲤亚科与野鲮亚科组成的姐妹群在宿主系统树上同样处在基部位置,寄生虫和宿主在进化上较为原始的地位得到了很好地相互印证。因而,本研究首次利用分子系统学手段分析指环虫属远缘物种间的系统关系,揭示了指环虫属与宿主鱼类之间存在协同进化关系。另外,本研究首次发现,野鲮亚科鱼类也可能是指环虫类的早期宿主,这与先前认为鲤亚科鱼类为指环虫类的祖先宿主的推测有所不同。     

林跳鼠亚科的系统学研究述评

林跳鼠亚科分布在亚洲和北美洲,虽然种类及数量都不多,但对该亚科的分类和系统发育关系一直存在争议,近几年对林跳鼠哑科分子系统学的研究,产生了一些与形态学、生物地理学等研究不同的结果.本文对林跳鼠亚科系统学研究的一些工作加以述评,归纳出林跳鼠亚科在系统学方面还存在的问题,并对林跳鼠亚科系统学的进一步研究提出了一些建议.     

基于28S rDNA C1-D2区的鳞盘虫科单殖吸虫系统学初步研究

首次利用核糖体28S rDNA C1-D2区序列对鳞盘虫科开展初步的系统学分析,探讨鳞盘虫科各亚科是否成立及其相互关系,并考察鳞盘虫属的单系性问题.结果表明:1)寄生在黄姑鱼Nibea albiflora上的Sinodiplectanotrema属虫种与鳞盘虫科虫种表现出较近的亲缘关系,因虫种后吸器不具鳞盘,故应纳入鳞盘虫科4亚科之一的Murraytrematoidinae亚科;2)本研究不支持Murraytrematoidinae亚科的单系性,并支持Doumingous(2004)废除Murraytrematoidinae亚科并将其中的Lobotrema和Murraytrema二属归入Diplectaninae亚科这一做法;3)对于Doumingous(2004)所提议的新Diplectaninae亚科是否为单系群需进一步探讨;4)本研究支持Lamellodiscinae亚科的单系性;5)7种鳞盘虫属虫种的分析结果显示鳞盘虫属具有明显的非单系性.今后需要将形态学分析和分子系统学分析结合起来,通过分析更多的虫种,才有可能理解鳞盘虫属及鳞盘虫科其它种类的适应辐射问题.     

新疆准噶尔盆地北缘早中新世的Metexallerix——新种

记述了准噶尔盆地北缘吃巴尔我义索索泉的Ｍｅｔｅｘａｌｌｅｒｉｘ ｊｕｎｇｇａｒｅｎｓｉｓ ｓｐ．ｎｏｖ。,该种在形态上较兰州早中新世的Ｍ．ｇａｏｌａｎｓｈａｎｅｎｓｉｓ原始,较蒙古早渐新世三达河组的Ｅｘａｌｌｅｒｉｘ ｈｓａｎｄａｇｏｌｅｎｓｉｓ进步,其亲缘关系与亚洲的短面猬类较近,而与北美的短面猬类较远。应用分支系统学的方法分析了短面猬亚科各属间及其相关类群的系统发育关系,结果表明,短面猬亚科为     

中国鲤科鱼类染色体组型的研究Ⅸ.鳊亚科9种鱼和鲴亚科1种鱼的染色体组型

我们曾报道过分布于湖北省的鳊、鲴亚科鱼类的核型。本文继续报道采自四川和广东省的鳊、鲴亚科另10种鱼的核型考察结果。       

浙江省鲴亚科鱼类寄生单殖吸虫三新种

在研究浙江省鲴亚科鱼类寄生单殖吸虫季节性动态的过程中,曾发现24种单殖吸虫寄生,其中3种为新种。现描述如下。文内量度以毫米为单位。 模式标本保存于杭州大学生物系。     

基于形态和分子数据确定缩颜蚜蝇族的系统分类地位

采用分子生物学方法 ,以缩颜蚜蝇族及食蚜蝇科 3类不同食性类群的代表种 (共 6属 7种 )为材料 ,对其核糖体RNA基因 (rDNA)的 5 .8S片段及转录间隔区(ITS)进行序列分析 ,并构建分子系统树 .同时 ,采用支序分析的方法 ,以缩颜蚜蝇族及我国有分布的食蚜蝇科其他族为材料 ,以成虫及幼期形态学性状为基础 ,结合染色体核型分析 ,对食蚜蝇科族级阶元的系统发育进行分析 .分子系统学及分支系统学研究结果表明 ,缩颜蚜蝇族与捕食性类群的亲缘关系较近 ,与腐食性类群的亲缘关系较远 .因而缩颜蚜蝇族应从现行分类系统中的迷蚜蝇亚科移入食蚜蝇亚科 ,其系统分类地位可有一个明确的定论 .     

Molecular systematics of Xenocyprinae (teleostei: cyprinidae): taxonomy, biogeography, and coevolution of a special group restricted in East Asia

We surveyed mitochondrial DNA (mtDNA) sequence variation in the subfamily Xenocyprinae from China and used these data to estimate intraspecific, interspecific, and intergeneric phylogeny and assess biogeographic scenarios underlying the geographic structure of lineages. We sequenced 1140 bp of cytochrome b from 30 individuals of Xenocyprinae and one putative outgroup (Myxocypris asiaticus) and also sequenced 297 bp of ND4L, 1380 bp of ND4, 68 bp of tRNA(His), and 69 bp of tRNA(Ser) from 17 individuals of Xenocyprinae and the outgroup (M. asiaticus). We detected high levels of nucleotide variation among populations, species, and genera. The phylogenetic analysis suggested that Distoechodon hupeinensis might be transferred to the genus Xenocypris, the taxonomic status of the genus Plagiognathops might be preserved, and species of Xenocypris and Plagiognathops form a monophyletic group that is sister to the genus Distoechodon and Pseudobrama. The introgressive hybridization might occur among the populations of X. argentea and X. davidi, causing the two species to not be separated by mtDNA patterns according to their species identification, and the process and direction of hybridization are discussed. The spatial distributions of mtDNA lineages among populations of Xenocypris were compatible with the major geographic region, which indicated that the relationship between Hubei + Hunan and Fujian is closer than that between Hubei + Hunan and Sichuan. From a perspective of parasite investigation, our data suggested that the fauna of Hexamita in Xenocyprinae could be used to infer the phylogeny of their hosts.     

异鲴的骨骼形态及其属的分类位置

对异鲴的骨骼形态进行了详细的描述并与丹亚科及鲴亚科代表种的骨骼特征进行了比较。结果显示异鲴与丹亚科在骨骼学性状缺乏共同离征,一系列的离征却表明它与再生鲴亚科鱼类紧密相关。这些离征包括：咽骨形态独特,前臂略长或与后臂等长;下咽齿侧扁,有明显的咀嚼面;基枕骨具有向下弯曲的基枕骨突,咽突而发达,椭圆形且向前突出;穿行于基枕骨的背大动脉通道接近咽突长;副蝶骨具有发达的龙骨突;前上颌骨短宽,下边缘为软骨;上颌骨外侧具突起;齿骨前背缘有外侧等。异鲴之置于丹亚科仅依据他们在围眶骨系的形态及排列上的相似性,而它和鲴亚科鱼类具有的一些共同离征表明它们可以形成姐妹群。因此,异鲴属在鲤科中的分类位置应该更加接近鲴亚科。     

鱼类寄生六鞭毛虫的研究（动鞭纲：双滴虫目：六鞭毛科）

本文报道六鞭毛科１８个新种,其中六鞭毛虫属１５种,旋核六鞭虫属３种,其简要形态记述于后,模式标本保存在中国科学院水生生物研究所鱼病学研究室。     

Molecular phylogenetic relationships of Eastern Asian Cyprinidae (Pisces: Cypriniformes) inferred from cytochrome b sequences

Cyprinidae, the largest fish family, comprises ap-proximately 210 recognized genera and 2010 species that are distributed widely in Eurasia, East Indian Is-land, Africa, and North America[1]. Species richness of this family is the greatest in East Asia, for example, China has 122 genera and more than 600 species. It is difficult to build a comprehensive phylogeny of Cy-prinidae due to the large number of genera and species. The classification of this family has been subject to revisions an…     

Molecular phylogenetic relationships of Eastern Asian Cyprinidae (Pisces: Cypriniformes) inferred from cytochrome <Emphasis Type="Italic">b</Emphasis> sequences

Complete mitochondrial cytochrome b sequences of 54 species, including 18 newly sequenced, were analyzed to infer the phylogenetic relationships within the family Cyprinidae in East Asia. Phylogenetic trees were generated using various tree-building methods, including Neighbor-joining (NJ), Maximum Parsimony (MP) and Maximum Likelihood (ML) methods, with Myxocyprinus asiaticus (family Catostomidae) as the designated outgroup. The results from NJ and ML methods were mostly similar, supporting some existing subfamilies within Cyprinidae as monophyletic, such as Cultrinae, Xenocyprinae and Gobioninae (including Gobiobotinae). However, genera within the subfamily “Danioninae” did not form a monophyletic group. The subfamily Leuciscinae was divided into two unrelated groups: the “Leuciscinae” in East Asia forming as a monophyletic group together with Cultrinae and Xenocyprinae, while the Leuciscinae in Europe, Siberia, and North America as another monophyletic group. The monophyly of subfamily Cyprininae sensu Howes was supported by NJ and ML trees and is basal in the tree. The position of Acheilognathinae, a widely accepted monophyletic group represented by Rhodeus sericeus, was not resolved.     

Permeability of the Body Wall of Romanomermis culicivorax to Lanthanum

Ultrastructural study of the body wall of preparasitic, parasitic, and postparasitic stages of Romanomermis culicivorax showed that the cuticle of all three stages was permeable to lanthanum. The cuticle of the parasitic stage was the thinnest and showed the greatest permeability. Lanthanum accumulated on the apical surfaces of the hypodermal cells but was not found intracellularly. The negative staining characteristics of lanthanum enhanced the detection of numerous smooth septate junctions in the hypodermis of the parasitic stage.     

武昌六前鞭虫胞器超微结构的研究

对武昌六前鞭虫胞器的超微结构进行了观察,发现R鞭毛复合体的内下方有分散的微管,两根R鞭毛复合体之间和外方具少量的粗面内质网,而虫体周边分布较多.粗面内质同外周被发达的微管.生毛体与胞核之间有胞咽和小盾结构.胞质中有较多的食物泡,未见到线粒体、高尔基体和表膜下微管结构.另外对粗面内质网的结构、功能以及种的鉴定等方面也作了讨论.       

根寄生植物种子萌发刺激物研究进展

根寄生植物是被子植物中一类寄生在寄主根部, 以摄取寄主水分和营养物质为生的特殊植物类群, 其种子萌发需要寄主萌发刺激物的诱导。该文主要阐述根寄生植物种子萌发的特异性, 以及目前已发现的刺激种子萌发的信号物质及其调节机制和生物合成途径, 并就萌发刺激物的识别机制及其在根寄生植物或丛枝菌根真菌与寄主建立寄生关系过程中所起的作用进行综述, 提出根寄生植物种子萌发研究中存在的问题, 并对其研究前景进行了展望。     

Carbohydrate and Amino Acid Fermentation in the Free-Living Primitive Protozoon Hexamita sp

Hexamita sp. is an amitochondriate free-living diplomonad which inhabits O(2)-limited environments, such as the deep waters and sediments of lakes and marine basins. C nuclear magnetic resonance spectroscopy reveals ethanol, lactate, acetate, and alanine as products of glucose fermentation under microaerobic conditions (23 to 34 muM O(2)). Propionic acid and butyric acid were also detected and are believed to be the result of fermentation of alternative substrates. Production of organic acids was greatest under microaerobic conditions (15 muM O(2)) and decreased under anaerobic (<0.25 muM O(2)) and aerobic (200 to 250 muM O(2)) conditions. Microaerobic incubation resulted in the production of high levels of oxidized end products (70% acetate) compared to that produced under anoxic conditions (20% acetate). In addition, data suggest that Hexamita cells contain the arginine dihydrolase pathway, generating energy from the catabolism of arginine to citrulline, ornithine, NH(4), and CO(2). The rate of arginine catabolism was higher under anoxic conditions than under microaerobic conditions. Hexamita cells were able to grow in the absence of a carbohydrate source, albeit with a lower growth rate and yield.