66 resultados para Cypriniformes.


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The identity of Schizothorax griseus Pellegrin, 1931, is clarified and the species redescribed. Three new species previously identified as S. griseus are described: S. nudiventris, from the Lancang Jiang, China; S. heterophysallidos, from the Nanpan Jiang

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<正> 胭脂鱼Myxocyprinus asiaticus(Bleeker),此鱼俗称火烧鳊、红鱼、燕雀鱼、紫鳊鱼、黄排、木叶盘等。鉴于目前国内有关胭脂鱼资料报道甚少,籍此,笔者不防将胭脂鱼的生活史初步综述如后。种类胭脂鱼属鲤形目Cypriniformes亚目Cyprinoidei胭脂鱼科Catostomidae。本科多产于北美洲,少数见于中美洲,据已知胭脂鱼仅美洲就有30余种,其中大口胭脂鱼(Icti obus

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National Natural Science Foundation of China (NSFC) [30225008, 30300036, 30530120]; Key Innovation Plan [KSCX2-SW-106]; National Basic Research Project in China [2005cb422005]; National Natural Science Foundation of China [30600062]

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Artificial interspecific hybrids between large scale loach P. dabryanus and tetraploid pond loach M. anguillicaudatus (Cobitidae, Cypriniformes) are viable. To detect the occurrence of possible natural hybridization, genetic analyses by using microsatellite markers were performed for natural populations of large scale loach and pond loach, the reciprocal laboratory hybrids, and "supposed hybrids" with ambiguous morphology. The fertility of the artificial hybrids was also tested. At one diagnostic microsatellite (Mac50), one out of 20 "supposed hybrids" was identified to be F-1 hybrid between the two loach species because it had the same genotype as that of the laboratory hybrids. The triploid hybrids between the two species were confirmed to be female-sterile. The results show that rare hybridization has occurred between diploid large scale loach and tetraploid pond loach in nature although it may have little effect in genetic introgression. This study is helpful for fish conservation and encourages further investigation on natural hybridization and introgression of loaches.

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The complete mitochondrial genome sequence of the Chinese hook snout carp, Opsariichthys bidens, was newly determined using the long and accurate polymerase chain reaction method. The 16,611-nucleotide mitogenome contains 13 protein-coding genes, two rRNA genes (12S, 16S) 22 tRNA genes, and a noncoding control region. We use these data and homologous sequence data from multiple other ostariophysan fishes in a phylogenetic evaluation to test hypothesis pertaining to codon usage pattern of O. bidens mitochondrial protein genes as well as to re-examine the ostariophysan phylogeny. The mitochondrial genome of O. bidens reveals an alternative pattern of vertebrate mitochondrial evolution. For the mitochondrial protein genes of O. bidens, the most frequently used codon generally ends with either A or C, with C preferred over A for most fourfold degenerate codon families; the relative synonymous codon usage of G-ending codons is greatly elevated in all categories. The codon usage pattern of O. bidens mitochondrial protein genes is remarkably different from the general pattern found previously in the relatively closely 9 related zebrafish and most other vertebrate mitochondria. Nucleotide bias at third codon positions is the main cause of codon bias in the mitochondrial protein genes of O. bidens, as it is biased particularly in favor of C over A. Bayesian analysis of 12 concatenated mitochondrial protein sequences for O. bidens and 46 other teleostean taxa supports the monophyly of Cypriniformes and Otophysi and results in a robust estimate of the otophysan phylogeny. (C) 2007 Published by Elsevier B.V.

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The Otocephala, a clade including ostariophysan and clupeomorph telcosts, represents about a quarter of total fish species diversity, with about 1000 gencra and more than 7000 species. A series of recent papers have defended that the origin of this clade and of its major groups may be significantly older than the oldest fossils of each of these groups suggest. Some of these recent papers explicitly defend a Pangean origin for some otocephalan groups Such as the Siluriformes or Cypriniformes. To know whether or not the otocephalans as a whole, and particularly the mainly freshwater, cosmopolitan otophysans could have originated before the splitting of the Pangean Supercontinent is of extreme importance, since otophysan fishes are among the most useful animal groups for the determination of historical continental relationships. In the present work we examined divergence times for each major otocephalan group by an analysis of complete mtDNA sequences, in order to investigate if these divergence times support the hypotheses advanced in recent studies. The complete mtDNA sequences of nine representative non-otocephalan fish species and of twenty-one representative otocephalan species was compared. The present study is thus, among the studies dealing with molecular divergence times of telcosts, the one in which a greater number of otocephalan species are included. The divergence times obtained support that the major otocephalan groups had a much older origin than the oldest fossil records available for these groups suggest. The origin of the Otocephala is estimated as having occurred about 282 Mya, with the origin of the Otophysi being estimated at about 251 Mya. (c) 2005 Elsevier B.V. All rights reserved.

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A microsatellite locus, MFW1, originating from common carp is highly conserved in flanking nucleotides but variable in repeat length in some fishes from different families of the Cypriniformes. This orthologous locus is polymorphic in approximately 58% of the species tested in the order and is inherited by Mendelian law. It proved to be a potentially good marker in population genetics and in the cyprinid species-breeding programme in which no microsatellite markers were available.

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The sequencing analysis of the mitochondrial DNA control region (mtCR DNA) was performed to assess the genetic divergence and population structure of the Chinese sucker Myxocyprinus asiaticus (Cypriniformes Catostomidae) using four sample lots from natural populations of the Yangtze River. The mtCR DNA sequences of approximately 920 base pairs were obtained. A total of 223 nucleotide positions were polymorphic, and these defined 39 haplotypes. Of the 39 haplotypes, 37 (90%) were not shared, and among the populations as a whole there was little sharing of haplotypes. The average haplotype diversity (0.958) and the average nucleotide diversity (0.052) indicated a higher level of genetic diversity of Chinese sucker through the river. Analysis of molecular variation (AMOVA) of data revealed significant partitioning of variance (P<0.001) among populations (60.29%), and within populations (39.71%). The topology according to the neighbor joining and maximum parsimony methods showed mosaic composition of the 39 haplotypes, suggesting that the populations wore not completely divergent. The pairwise F statistic values, however, indicated that the population structuring existed to some extent among the geographic populations. There was a positive relationship between the aquatic distance and the genetic distance (Fst) among the populations (P<0.05). Based on our data, it is suggested that genetic drift, gene flow, and stochastic events are the possible factors influencing the population structure and genetic variation.

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Cyprinidae is the largest fish family in the world and contains about 210 genera and 2010 species. Appropriate DNA markers must be selected for the phylogenetic analyses of Cyprinidae. In present study, the 1st intron of the S7 ribosomal protein (r-protein) gene is first used to examine the relationships among cyprinid fishes. The length of the 1st intron obtained by PCR amplification ranges from 655 to 859 by in the 16 cyprinid species investigated, and is 602 by in Myxocyprinus asiaticus. Out of the alignment of 925 nucleotide sites obtained, the parsimony informative sites are 499 and occupy 54% of the total sites. The results indicate that the 1st intron sequences of the S7 r-protein gene in cyprinids are rich in informative sites and vary remarkably in sequence divergence from 2.3% between close species to 66.6% between distant species. The bootstrap values of the interior nodes in the NJ (neighbor-joining) and MP (most-parsimony) trees based on the present S7 r-protein gene data are higher than those based on cytochrome b and the d-loop region respectively. Therefore, the 1st intron sequences of the S7 r-protein gene in cyprinids are sensitive enough for phylogenetic analyses, and the 1st intron is an appropriate genetic marker for the phylogenetic reconstruction of the taxa in different cyprinid subfamilies. However, attempts to discuss whether the present S7 r-protein gene data can be applied to the phylogeny of the taxa at the level of the family or the higher categories in Cypriniformes need further studies.

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Zhang 等(2000)根据口唇部结构把鲤形目Cypriniformes 鲤科Cyprinidae 野鲮 亚科Labeoninae 鱼类分为三个类群。其中第二个类群鱼类的特征是吻皮发达向 腹面下包、上唇退化、下唇向复杂的形态演变,有的形成似吸盘状的雏形构造。 在整理广西鱼类标本时,发现来自广西桂林大埠的十余尾标本不能归到野鲮亚科 任何属中,在这里建立一个新属-狭吻鱼属(Stenorhinchus)。狭吻鱼属的口唇部结 构具有野鲮亚科第二类群鱼类的特征。本研究的目的是为了探讨狭吻鱼属的有效 性及其在野鲮亚科第二类群中的系统位置。传统的观点(张鹗,1998)认为异华 鲮属Parasinilabeo 与唇鱼属Semilabeo、泉水鱼属Pseudogyrinocheilus 的亲缘关 系较近,苏瑞凤(2001)认为异华鲮属与华缨鱼属、直口鲮属构成一个单系群, 本研究的另一目的是要探讨异华鲮属在野鲮亚科中的分类地位,同时描述了异华 鲮属一新种-长鳍异华鲮(Parasinilabeo longiventralis)。 基于外部形态和骨骼特征,利用分支系统学原理和方法对野鲮亚科第二类群 鱼类进行系统发育研究。选择野鲮亚科第二类群的直口鲮属(Rectoris)、穗唇鲃 属(Crossocheilus)、角鱼属(Akrokolioplax)、华缨鱼属(Sinocrossocheilus)、拟 缨鱼属(Pseudocrossocheilus)、异华鲮属(Parasinilabeo)、唇鱼属(Semilabeo)、 泉水鱼属( Pseudogyrinocheilus ) 和第一类群的鲮(Cirrhinus) 、舌唇鱼 (Lobocheilus)、脂孟加拉鲮(Bangana)作为内群,以鲃亚科的刺鲃(Spinibarbus caldwelli)、大鳞高须鱼(Hypsibarbus vernayi)作为外群。利用外群比较法选取 性状,进行编码后建立一个性状状态矩阵。然后应用软件MacClade4.0 和Paup4.0 进行分析。本研究选取61 个性状来构建系统发育树。系统发育树结果表明:(1) 野鲮亚科第二类群的鱼类构成一个单系群,在这里把它们命名为穗唇鲃组;(2) 狭吻鱼属是个有效属,应置于野鲮亚科第二类群并与唇鱼属、泉水鱼属的亲缘关 系最近;(3)异华鲮属与狭吻鱼属、唇鱼属、泉水鱼属的亲缘关系较密切,在4 属之中,它是较早分化出来的类群; (4)宽唇华缨鱼和三齿华缨鱼不聚成姐妹 群,华缨鱼属不构成单系群;(5)直口鲮和宽唇华缨鱼的分类地位不稳定,需要 今后进一步的分子生物学研究确认。

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本研究对岭鳅属鱼类进行了分类整理。对目前鉴定出的岭鳅属鱼类6 个种63 尾鱼类标本的28 个可量性状和6 个可数性状进行了测量和计数;对分类学上存 在疑问的种的测量数据进行了主成分分析。结合测量、计数以及主成分分析的结 果,并应用系统发育物种概念,评价岭鳅属鱼类物种的有效性,并描述岭鳅属鱼 类两新种。主要结论如下: 1. 岭鳅属的主要鉴别特征为:前、后鼻孔分开一短距离,前鼻孔位于一个管状 系统中,管状系统的末端延长成须状;骨质鳔囊为敞开型;上颌无齿状突起。 借此特征岭鳅属鱼类与条鳅亚科(Nemachilinae)其它属级类群完全区分开 来。 2. 小眼岭鳅(Oreonectes microphthalmus)采自广西都安、罗城。根据其尾鳍叉 形,眼睛退化仅残留一黑色素眼点,全身裸露无鳞,头部的眶下管孔为3+0 以及眶上管孔为7,将小眼岭鳅描述成岭鳅属一新种。 3. 多斑岭鳅(Oreonectes polystigmus)采自广西桂林大埠。根据其侧线不完全, 仅在头部后方有6 个侧线孔,头部的眶上管孔为7,眶下管孔为4+7 以及身 体布满不规则的斑点或斑块而将其描记成岭鳅属一新种。 4. 分布于广西都安的透明岭鳅(Oreonecetes translucens)与分布于贵州荔波的 长须盲副鳅(Paracobitis longibarbatus)、荔波盲条鳅(Nemacheilus liboensis) 和荔波岭鳅(Oreonectes liboensis)是同一物种,并根据其前鼻孔与后鼻孔紧 相邻、骨质鳔囊侧囊的后壁为骨质、雄性胸鳍外侧鳍条增宽变硬的特征,将 它们归属为高原鳅属(Triplophysa),有效名称为长须盲高原鳅(Triplophysa longibarbatus)。

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The differentiation of spermatids in Hoplias malabaricus is characterized by chromatin compaction, flagellum development, nuclear rotation, nuclear fossa formation, and excess cytoplasm elimination. In the resulting spermatozoon, the head is round and the nucleus contains chromatin compacted in thick filaments, peripherically arranged, to a central electron-lucent area. The acrosome is absent. The nuclear fossa is eccentric but not pronounced. The proximal centriole penetrates it and is oblique to the flagellum. The long midpiece has several converging elongate vesicles, forming membranous hoops in the initial segment of the flagellum, but has no cytoplasmic channel. The mitochondria are elongate and branched or C-shaped and located around the initial segment of the axoneme. The lateral flagellum does not show lateral projections. The ultrastructural characteristics of H. malabaricus spermatozoa are similar to the Cypriniformes. (C) 2001 the Fisheries Society of the British Isles.

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A espermiogênese nas espécies Steindachnerina insculpta, Cyphocharax gillii, C. modestus, C. spilotus e Potamorhina altamazonica de Curimatidae é caracterizada pelo desenvolvimento lateral do flagelo, rotação do núcleo, formação excêntrica da fossa nuclear e cromatina compactada em fibras espessas. Estes espermatozóides exibem uma cabeça esférica contendo um núcleo com cromatina altamente condensada em fibras espessas com pequenas áreas eletronlúcidas, e sem acrossoma. A fossa nuclear é do tipo moderado e excêntrico, penetrada pelo complexo centriolar. A peça média é pequena, tem muitas vesículas alongadas e um curto canal citoplasmático. Mitocôndrias podem ser alongadas, ramificadas ou em forma de C, e são separadas do segmento inicial do axonema pelo canal citoplasmático. O flagelo contém a estrutura clássica do axonema (9+2) e tem um compartimento membranoso na região inicial; não possui expansões laterais (fins). Somente pequenas diferenças foram observadas entre as espécies e gêneros analisados de Curimatidae. A espermiogênese e os espermatozóides de Curimatidae têm muitas das características encontradas em quase todas as outras espécies de Characiformes. Por outro lado, a presença de um compartimento membranoso na região inicial do flagelo dos curimatídeos, uma estrutura comum nos espermatozóides de muitos cipriniformes, é desconhecida em outros characiformes. Discute-se sobre a espermiogênese e espermatozóides de Characiformes.

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This study describes the occurrence and the seasonality of parasites of cultivated fish from a fee fishing farm located in Guariba, São Paulo State, Brazil (21°15'22'' S, 48°18'58'' W and 595 m of altitude), from August, 2001 to July, 2002. The presence of parasites was researched in pacu Piaractus mesopotamicus (Characidae), common carp Cyprinus carpio (Cyprinidae), nile-tilapia Oreochromis niloticus (Cichlidae), tambacu hybrid (male of P. mesopotamicus x female of tambaqui-Colossoma macropomum) and piraputanga Brycon hillari (Characidae). Results demonstrate that out of 100 fish examined, 15% were sponged for at least one of the following parasites: Trichodina sp.; monogenean helminths; copepodits of Lemaea cyprinacea; adults of L. cyprinacea; or Dolops carvalhoi. In decreasing order, the susceptibility degree of the hosts was C. carpio, P. mesopotamicus, B. hillari, tambacu hybrid and O. niloticus. In decreasing order the reported parasites were monogenean helminths, Dolops carvalhoi, Trichodina sp., adults of Lernaea cyprinacea and their young shapes.