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1.
记述采自中国广西壮族自治区邕江和郁江鳅属Cobitis 1新种,南方鳅Cobitis australis sp.nov..通过扩增其线粒体细胞色素b基因,与已知鳅属和益秀朝鲜鳅属Iksookimia 物种进行遗传距离比较,并构建系统发育树,结合形态分析,确认其为1新种.南方鳅与本属其它种类的区别主要为:噶氏斑纹分界不明显(Gambetta's pigmentation pattern),斑纹具两性异形.雄性背部斑纹不规则,约17 ~ 20个,背鳍后斑纹融合为马鞍形;雌性背部斑纹约13个,背鳍前斑纹在体侧延伸为三角形.体侧中线11 ~13个不规则的“V”形或倒三角形斑纹,雄性头后4~5个小斑纹,雌性1~2个小斑纹.背部和体侧中线之间为形状和大小不规则的斑纹,雄性多于20个,该处斑纹与背部和体侧中线斑纹有融合;雌性少于20个,无融合.背鳍和尾鳍各具有4~5列点状条纹;雄性胸鳍第1根分枝鳍条基部的骨质突起(lamina circularis)指状,第1根分支鳍条延长,胸鳍似旗状;体鳞较大,延长,卵圆形,鳞焦略大,基位;颏叶不发达,末端钝圆;须短,其长等于或略小于眼径.新种体色斑纹与益秀朝鲜鳅属种类相似,新种与益秀朝鲜鳅Iksookimia koreensis(Kim,1975)和斑纹益秀朝鲜鳅Iksookimia pumila(Kim et Lee,1987)的主要区别是,前者背鳍和尾鳍各具4~5条斑纹,背部斑纹和体侧中线斑纹不相连,体侧中线11 ~13个宽而短的倒三角形斑纹;益秀朝鲜鳅背鳍和尾鳍各具有3~4列条纹,体侧中线下13~ 14个窄而长的倒三角形斑纹;斑纹益秀朝鲜鳅背鳍和尾鳍各具有2~3列条纹,背部斑纹和体侧中线斑纹相连,两列斑纹之间斑块少于10个,体侧中线9 ~10个宽而长的条状或倒三角形斑纹.新种与盈德益秀朝鲜鳅Iksookimia yongdokensis Kim et Park,1997、休氏益秀朝鲜鳅Iksookimia hugowolfeldi Nalbant,1993和长身益秀朝鲜鳅Iksookimia longicorpus(Kim,Choi and Nalbant,1976)的主要区别是,前者骨质突起指状,后者骨质突起圆盘状.  相似文献   
2.
中国广西金线鲃属一新种(鲤形目,鲤科,鲃亚科)   总被引:2,自引:1,他引:1  
2001年5月作者于广西环江县驯乐乡顺宁村采集到金线鲃属盲鱼5尾,经鉴定为一新种.新种眼睛完全退化,头后急剧隆起但尚未形成额骨突等体型特征与无眼金线鲃Sinocyclocheilus anophthalmus Chen et Chu,1988相似,而明显有别于属内其他物种.但两者在以下性状上又存在明显区别:1)新种背鳍硬刺纤弱;而无眼金线鲃的背鳍硬刺比较粗壮;2)新种背部自额骨后隆起,但是额骨顶部并不隆起;无眼金线鲃则自眼眶上方的额骨顶部开始显著隆起,直至肩部;3)新种侧线平直;无眼金线鲃的侧线在腹鳍和臀鳍之间的上方有一比较明显的向上弯曲;4)新种胸鳍长,超过腹鳍起点;无眼金线鲃胸鳍不超过腹鳍起点;5)分布区亦有所不同,新种分布于柳江水系;无眼金线鲃则分布于南盘江水系.此外,在一些可测性状上二者亦有区别,在标准长与体高和头长的比例、尾柄长与尾柄高的比例、侧线鳞的数目等性状上都有所差异.  相似文献   
3.
用mtDNA 12S rRNA序列变异检验鲤形目鱼类系统发育关系   总被引:9,自引:0,他引:9  
刘焕章 《遗传学报》2004,31(2):137-142
通过对鲤形目鱼类5个科的代表类群的完整线粒体12S rRNA进行测序和分析,以检验目前的形态学假说。经序列比对后,有1000个位点,其中467个位点在茎区,533个在环区;有395个位点为变化位点,其中267个为系统发育信息位点。采用邻接法和最大简约法进行了系统发育分析,其结果支持鲤科鱼类成为一个单系群,非鲤科的鲤形目鱼类成为另一个单系群的观点,这与Siebert提出的假说相一致。鲤科鱼类包含3个主要的分支,即鱼丹系、鲤系和雅罗鱼系;但在非鲤科鲤形目鱼类中,其关系不能得到很好的解决,其中鳅科是复系,平鳍鳅科、条鳅亚科和花鳅亚科可能有较近的亲缘关系。  相似文献   
4.
记述了采自云南省沾益县德泽乡牛栏江水域的平鳍鳅科爬岩鳅属鱼类1新种,牛栏爬岩鳅 Beaufortia niulanensis Chen,Huang et Yang,sp.nov..其特征:背鳍分支鳍条7,腹鳍分支鳍条21,侧线鳞90~95,胸鳍起点相对于鼻孔和眼前缘之间,背鳍起点相对于腹鳍起点至其基部后缘的中点稍后,肛门位于腹鳍基后缘至臀鳍起点间的中点,腹鳍末端接近肛门,这些特征组合可以将新种与同属的其他2个相近种,即四川爬岩鳅B.szechuanensis(Fang)和中间爬岩鳅B.intermedia Tang et Wang区别开来.  相似文献   
5.
1996年11月至1997年6月,于雅砻江下游干流及其支流鳡鱼河中采获一批白鱼属Anabarilius鱼类标本,经鉴定为西昌白色1新亚种。命名为西昌白色雅砻亚种Anabarilius liui yalongensis subsp.nov。与其它3个亚种的主要鉴别特征是:第1鳃弓外侧鳃耙为7—10,其余3个亚种分别为:西昌指名亚种A.liui liui为12-14,程海亚种A.liui chenghaiensis 15-16,宜良亚种A.liui yiliangensis10-12。种内亚种分化主要是受到同域生态隔离和地理隔离作用的影响。  相似文献   
6.
The variability in the stenotopic miniature rasborine Boraras maculatus (Cypriniformes: Danionidae: Rasborinae) across acidic-water habitats of Peninsular Malaysia (PM) was investigated using two molecular markers (the mitochondrial cytochrome c oxidase subunit I [COI] gene and the nuclear rhodopsin gene), as well as morphological evidence. Molecular phylogenetic analyses revealed differentiation among populations of B. maculatus in PM with the distinction of four allopatric lineages. Each of them was recognized as a putative species by automatic species delimitation methods. These lineages diverged from each other between 7.4 and 1.9 million years ago. A principal component analysis (PCA) was conducted to examine the multivariate variation in 11 morphometric measurements among three of these lineages. PCA results showed a significant overlap in morphological characteristics among these lineages. Additionally, a photograph-based machine learning approach failed to fully differentiate these lineages, suggesting limited morphological differentiation. B. maculatus represents a case of morphological stasis in a stenotopic miniature species. Strong habitat preference, coupled with long-term habitat fragmentation, may explain why each lineage of B. maculatus has a restricted distribution and did not disperse to other regions within and outside of PM, despite ample possibilities when the Sunda shelf was emerged and drained by large paleodrainages for most of the past 7 million years. The conservation status of B. maculatus and its peat swamp habitats are discussed, and it is concluded that peat swamps comprise several evolutionary units. Each of these units is considered a conservation unit and deserves appropriate protection.  相似文献   
7.
本文根据系统学原理,提出了建立新类元的依据;并据此从分类和系统发育上论证了近金线属AnchicyclocheilusLietLan独立成属的可能性,认为应将近金线属归于金线属;修订了金线属SinocyclocheilusFang的鉴别特征。  相似文献   
8.
Two new species, Telestes dabar and Telestes miloradi, are described on the basis of morphological comparisons of isolated geographical populations of fishes identified earlier as Telestes metohiensis. A lectotype is designated for Telestes metohiensis, whose range is shown to include waters of Gatačko, Cerničko, and Nevesinjsko poljes in Eastern Herzegovina. Telestes dabar from Dabarsko Polje (Eastern Herzegovina) and Telestes miloradi from Konavosko Polje (south Croatia) share with Telestes metohiensis the following combination of characters that distinguish them from the rest of the genus Telestes: pharyngeal teeth in one row, usually 5–4; preoperculo-mandibular canal not communicating with the infraorbital canal; mouth subterminal, the tip of the mouth cleft on or below the level of the ventral margin of the eye; postcleithrum minute or absent; ventral portion of the trunk with a dark stripe on a pale background; and dorsal portion of trunk uniformly dark and bordered ventrally by a dark midlateral stripe. Telestes dabar and Telestes miloradi are distinguishable from Telestes metohiensis in usually having 8½ branched dorsal-fin rays (vs. usually 7½), 9 or 10 gill rakers (vs. 7–10, usually 8), and the dark stripe on the ventral portion of the trunk below the main pigmented area of the back narrow and usually not reaching posteriorly to the caudal peduncle (vs. dark stripe wide and extending posteriorly to the caudal peduncle). Telestes dabar is distinguished from Telestes miloradi by having scales on most of the body situated close to one another and overlapping in a region behind the pectoral girdle and usually on the caudal peduncle (vs. overlapping scales on most of the body); the lateral line usually incomplete and interrupted, with 24–69, usually 54–65, total scales (vs. lateral line usually complete, with 55–67 total scales); scales above and below the lateral line slightly smaller than lateral-line scales (vs. of about equal size); head width 43–52% HL (vs. 48–58% HL); and lower jaw length 10–12% SL or 36–41% HL (vs. 8–10% SL or 33–38% HL). Telestes miloradi, a very local endemic species,is known only by historical samples. Telestes dabar is an abundant fish in Dabarsko Polje, but its range is critically restricted during the dry season by a few permanent sources. Nothing is known about its occurrence in underground karst waters.  相似文献   
9.
The phylogenetic relationships of species are fundamental to any biological investigation, including all evolutionary studies. Accurate inferences of sister group relationships provide the researcher with an historical framework within which the attributes or geographic origin of species (or supraspecific groups) evolved. Taken out of this phylogenetic context, interpretations of evolutionary processes or origins, geographic distributions, or speciation rates and mechanisms, are subject to nothing less than a biological experiment without controls. Cypriniformes is the most diverse clade of freshwater fishes with estimates of diversity of nearly 3,500 species. These fishes display an amazing array of morphological, ecological, behavioral, and geographic diversity and offer a tremendous opportunity to enhance our understanding of the biotic and abiotic factors associated with diversification and adaptation to environments. Given the nearly global distribution of these fishes, they serve as an important model group for a plethora of biological investigations, including indicator species for future climatic changes. The occurrence of the zebrafish, Danio rerio, in this order makes this clade a critical component in understanding and predicting the relationship between mutagenesis and phenotypic expressions in vertebrates, including humans. With the tremendous diversity in Cypriniformes, our understanding of their phylogenetic relationships has not proceeded at an acceptable rate, despite a plethora of morphological and more recent molecular studies. Most studies are pre-Hennigian in origin or include relatively small numbers of taxa. Given that analyses of small numbers of taxa for molecular characters can be compromised by peculiarities of long-branch attraction and nodal-density effect, it is critical that significant progress in our understanding of the relationships of these important fishes occurs with increasing sampling of species to mitigate these potential problems. The recent Cypriniformes Tree of Life initiative is an effort to achieve this goal with morphological and molecular (mitochondrial and nuclear) data. In this early synthesis of our understanding of the phylogenetic relationships of these fishes, all types of data have contributed historically to improving our understanding, but not all analyses are complementary in taxon sampling, thus precluding direct understanding of the impact of taxon sampling on achieving accurate phylogenetic inferences. However, recent molecular studies do provide some insight and in some instances taxon sampling can be implicated as a variable that can influence sister group relationships. Other instances may also exist but without inclusion of more taxa for both mitochondrial and nuclear genes, one cannot distinguish between inferences being dictated by taxon sampling or the origins of the molecular data.  相似文献   
10.
Conservation status, identification, distribution, abundance, habitat and ecology, conservation actions and recommendations of a endemic cyprinid fish, Cyprinus micristius were introduced based on data and knowledge from a GEF project in Lake Dianchi, Yunnan, China.  相似文献   
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