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1.
赵俊  李文卫 《动物学研究》1997,18(3):243-246
本文记述采自湖南吉首的鲤科鱼类1新种,命名为吉首光唇鱼Acrossocheilus jishouensis sp.nov.。新种有以下与同属其他种类相区别的特点:下唇两侧瓣间隙小,几相接触;背鳍末根不分支鳍条柔软不加粗,后缘光滑;背鳍及臀鳍鳍条间膜有黑色条纹;体侧具不规则的大块黑斑或具模糊不清的垂直或纵行条纹等。新种与半刺光唇鱼A.hemispinus hemispinus和带半刺光唇鱼A.hemispinus cinctus较为相似。  相似文献   

2.
广西金线Ba属一新种   总被引:2,自引:0,他引:2  
李维贤  肖蘅 《动物学研究》2000,21(2):155-157
描记采于广西凌云县泗城镇沙洞地下河中的金线Ba属1新种,以采集地县名命名为凌云金线BaSinocyclocheilus lingyunensis sp.nov.。新种以侧线鳞71-78对48-50;背鳍最末不分枝鳍条下半部为硬刺,后缘有锯齿对纤细柔软,光滑无锯齿等特征区别于相近种季氏金线BaS.jii Zhang etDai。  相似文献   

3.
珠江水系鱼类一新纪录——带刺光唇鱼(鲤形目:鲤科)   总被引:1,自引:0,他引:1  
2008年5月及2010年8月在广东省增城市及河源市采得一批鱼类标本,其中20尾经鉴定为珠江水系鱼类新纪录——带刺光唇鱼(Acrossocheilus spinifer Yuan,WuZhang,2006)。该种主要鉴别特征包括:(1)体侧具有5~6条垂直的黑色条纹,每条约占2列鳞片宽,向下延伸至侧线以下2行鳞片,呈对称或不对称分布;(2)第2条垂直条纹位于背鳍末根不分枝鳍条的下方;(3)背鳍末根不分枝鳍条为粗壮的硬刺,后缘具细小的锯齿;(4)背鳍鳍间膜外缘2/3黑色。标本现保存于华南师范大学生命科学学院鱼类标本室。  相似文献   

4.
东方薄鳅Leptobolia orientalis,新种(图1) 鉴别特征 本新种与桂林薄鳅Leptobotia guilinensis Chen近似,主要区别:眼下刺后伸达眼中央,而后者达眼后缘,体具11—12垂直宽带纹,延伸至腹部,而后者体具15—18不规则垂直狭条纹,延伸至侧线上部,尾柄的垂直条纹或为马鞍形斑点所替代,腹鳍起点位于背鳍第一根分枝鳍条的下方,而后者的腹鳍起点与背鳍起点相对或稍前。  相似文献   

5.
广西高原鳅属鱼类一穴居新种记述   总被引:11,自引:0,他引:11  
2003年1月,在广西壮族自治区天峨县红水河水系地下河采集到一批盲鱼标本。经鉴定,为高原鳅属Triplophysa一未经发表的新种。新种天峨高原鳅Triplophysa tianeensis sp.nov.与个旧盲高原鳅T.gejiuensis、石林盲高原鳅T.shilinensis、阿庐高原鳅T.aluensis和南丹高原鳅T.nandanensis相似;本新种腹鳍末端不达肛门,尾鳍分枝鳍条16,可进一步与个旧盲高原鳅和石林盲高原鳅(腹鳍末端达到肛门,尾鳍分枝鳍条14-15)相区别;本新种背鳍起点位于体之中点、腹鳍起点之后,肛门紧靠臀鳍起点,可进一步与阿庐高原鳅(背鳍起点靠近吻端、位于腹鳍起点之前,肛门距臀鳍起点仍有一段距离)相区别。本新种与同分布于红水河水系的南丹高原鳅Triplophysa nandanensis Lan et al.较为相似;但二者区别明显:新种背鳍分枝鳍条7、胸鳍分枝鳍条9、腹鳍分枝鳍条6、背鳍外缘平截、背鳍起点位于腹鳍起点之后,后者背鳍分枝鳍条8、胸鳍分枝鳍条10~11、腹鳍分枝鳍条7、背鳍外缘凹入、背鳍起点位于腹鳍起点之前;此外,新种的穴居特征更为显著:眼极度退化、头长为眼径16.8—32.8(25.0)倍、部分个体无色素斑且各鳍无斑点,而南丹高原鳅眼小、头长为眼径4.7~9.0(7.5)倍、体和头背侧密布云状斑且各鳍均具点状斑。  相似文献   

6.
广西条鳅亚科鱼类二新种(鲤形目:鳅科)   总被引:12,自引:0,他引:12  
本文记述采自广西西江水系河池地区的条鳅亚科鱼类二新种。后鳍岭鳅,新种Oreonectes retrodorsalis sp.nov.与同属种的区别主要表现在其背鳍起点的位置较后、背鳍和臀鳍分枝鳍条数目较少、尾鳍后缘凹入、头较小和属柄较短等方面。南丹高原鳅,新种Triplophysa nandanensis sp.nov.则以头较大、吻较短、眼间距较狭、尾柄较短且高、背鳍分枝鳍条较多、尾鳍深叉形等易  相似文献   

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2012年6—7月,于广西壮族自治区凌云县逻楼镇附近一洞穴采集到金线鲃属一新种,并命名为安水金线鲃(Sinocyclocheilus anshuiensis sp.nov.)。该新种背鳍末根不分枝,鳍条基部为硬刺,后缘具锯齿,后半部柔软分节;背鳍分枝鳍条7;腹鳍起点位于背鳍起点之前;头后急剧隆起,头背交界处具一伸向上前方的肉质额骨突;侧线鳞34~38,与其相邻的上、下鳞片大小相当;尾柄上、下缘具发达肉质鳍褶。以上组合特征可与金线鲃属其他种类相区别。  相似文献   

8.
我国结鱼属鱼类的系统分类及一新种的记述   总被引:3,自引:1,他引:2  
结鱼属(Tor Gray)是鲃亚科中以下唇的唇后沟相连、侧瓣之间具中叶为共同离征的一个自然类群。我国结鱼属有3个亚属9个种(亚种),其中包括一个新种,即半刺结鱼Tor(Tor)hemispinus,sp.nov.其主要鉴别特征是:背鳍最后不分枝鳍条有一半分节柔软,下唇中叶很短、吻须长、侧线鳞较多。 在鲃亚科中,下唇及唇后沟的演变具有划分属级特征的意义。从唇后沟中断到相通,直至中叶的出现,反映从四须鲃Barbodes到圆唇鱼Cyclocheilich-thys再到结鱼的演化过程,这正是它们从杂食性过渡到底栖性的结果。在结鱼中,随着底栖适应性的进一步加强,中叶由雏形发展为舌状的一个序列,呈现与食性相关的形态变异。半刺结鱼的中叶结构标志着类似圆唇鱼的祖先已经完成了向结鱼演化的初级阶段,因此它是结鱼属中迄今知道的最为原始的一个种。最后,通过特征分析,对已知9个种(亚种)的系统发育,用分支图解加以表示。  相似文献   

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在整理华缨鱼属标本时发现,1993年9月在广西壮族自治区天峨县红水河水系地下河采集到的一批标本为一个未经发表的新种,新种订名为大眼华缨鱼(Sinocrossocheilus megalophthalmus)。其下咽齿2行,可与下咽齿3行的7种华缨鱼相区别,而与属内同样具2行下咽齿的贵州华缨鱼(S.guizhouensis)、小口华缨鱼(S.microstomatus)和宽唇华缨鱼(S.labiatus)亲缘关系较近。但:(1)新种胸鳍中点上方无黑斑,背鳍分枝鳍条7,腹鳍分枝鳍条7,背鳍前鳞15—16,眼大,头长为眼径2·5—3·1倍,眼径为头宽44·7%—57·8%,吻须后伸至前后鼻孔之间或眼前缘,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,体长为尾柄高8·9—10·7倍,头长为吻长2·5—3·7倍,可与贵州华缨鱼(胸鳍中点上方有一明显黑斑,背鳍分枝鳍条8,腹鳍分枝鳍条8,背鳍前鳞12—14,头长为眼径4·0—5·0倍,眼径为头宽16·6%—20·7%,吻须后伸不达后鼻孔后缘,口角须后伸至眼前缘,体长为尾柄高7·2—8·2倍,头长为吻长1·9—2·2倍)相区别;(2)新种背鳍前鳞15—16,侧线鳞39—40,侧线上鳞4·5—5·5,背鳍分枝鳍条7,鳃耙13,腹鳍末端伸达肛门,眼径为头宽44·7%—57·8%,可与宽唇华缨鱼(背鳍前鳞22,侧线鳞42—45,侧线上鳞6·5,背鳍分枝鳍条8,鳃耙10,腹鳍末端不达肛门,眼径为头宽23·3%—30·0%)相区别;(3)新种与同水系的小口华缨鱼在鳍条数、侧线鳞、体色、斑纹等方面最为相似,但新种围尾柄鳞14/16,眼大,头长为眼径2·5—3·1倍,腹鳍末端伸达肛门,口角须后伸至眼前缘至眼中之间或眼中至眼后缘之间,吻皮边缘深裂成小穗,背鳍起点距吻端较距尾鳍基为近,背鳍长大于头长,体长为尾柄长4·8—5·9倍,头长为吻长2·5—3·7倍,尾柄长为尾柄高1·6—2·1倍,可与之(围尾柄鳞12,眼小,头为眼径4·4—4·6倍,腹鳍末端不达肛门,口角须伸达眼下方,吻皮边缘不开裂或开裂不明显,背鳍起点距吻端等于距尾鳍基,背鳍条约等于头长,体长为尾柄长6·1—6·4倍,头长为吻长2·1—2·4倍,尾柄长为尾柄高1·4—1·5倍)相区别。  相似文献   

10.
系统整理了中国刺鳅属鱼类Mastacembelus,记述2新种,腹纹刺鳅M.strigiventus Zhouet Yang,sp.nov.和三叶刺鳅M.triolobus Zhouet Yang,sp.nov.及中国1新纪录种,云斑刺鳅M.oatesii(Boulenger)。新种模式标本分别保存于中国科学院昆明动物研究所(KIZ)鱼类标本库和西南林业大学(SWFC)。腹纹刺鳅与三叶刺鳅、大刺鳅的区别在于:背鳍、臀鳍与尾鳍基部大部愈合,但具缺刻相区分;体侧前部具4~5条褐色纵条纹,最下1条常断续,全部纵纹至肛门前方渐成网格交叉或断续;腹面亦具1条明显褐色纵纹,有时分歧形成小网格。三叶刺鳅区别于腹纹刺鳅及大刺鳅的主要特征包括:背鳍条、臀鳍条和尾鳍条数目均少;背鳍、臀鳍与尾鳍仅在基部相连,在端部分开,能明显区分;除背部的黑色大斑块外,体无六角状环纹或锯齿状纹,腹面亦无斑纹;头长为头宽3.5倍以下,为吻长2.8倍以下。云斑刺鳅以下面组合特征区别于三叶刺鳅和腹纹刺鳅:背鳍条,臀鳍条数目均少,尾鳍条数目相对较多;背鳍、臀鳍与尾鳍仅基部愈合;体侧具云状斑,背部具14~15个褐色斑块,腹面无纵纹或网眼斑;头长为头宽4.0倍以上,为吻长3.0倍以上。  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   

16.
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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