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1.
Marine ecosystems provide a wide variety of diverse habitats that frequently promote migration and ecological adaptation. The extent to which the geographic distribution of marine organism has reshaped by human activities remains underappreciated. The limitations intrinsic to morphology-based identification systems have engendered an urgent need for reliable genetic methods that enable the unequivocal recognition of fish species,particularly those that are prone to overexploitation and/or market substitution. In the present study, however, an attempt has been taken to identify two locally adapted fish species, Siganus sutor(Valenciennes, 1835) and Seriolina nigrofasciata(Rüppell, 1829) of order Perciformes, which happens to be the first record in Odisha coast,Bay of Bengal. The diagnostic characteristics of Siganus sutor are: dorsal fin XIII-10, anal fin VII-9, pectoral fin 15,pelvic fin II-3, while that of Seriolina nigrofasciata dorsal fin VI-I-35, anal fin I-17, pectoral fin 16, pelvic fin 5. All COI barcodes generated in this study were matched with reference sequences of expected species, according to morphological identification. Bayesian and likelihood phylogenetic trees were drawn based on DNA barcodes and all the specimens clustered in agreement with their taxonomic classification at the species level. The phylogeographic studies based on haplotype network and migration rates suggest that both the species were not panmitic and the high-frequency population distribution indicates successful migration. The result of this study provides an important validation of the use of DNA barcode sequences for monitoring species diversity and changes within a complex marine ecosystem.  相似文献   

2.
Codium, one of the largest marine green algal genera, is difficult to delimit species boundary accurately based on morphological identification only. DNA barcoding is a powerful tool for discriminating species of seaweeds. The plastid elongation factor TU(tuf A) is considered as maker to perform DNA barcoding of green algal species than rbc L gene due to universality and rapid evolution rate. We conducted DNA barcoding application to Codium specimens from the Jeju Island, Korea to overcome the limit of morphological identification and to confirm the species diversity. As a result of applying tuf A marker, we newly generated fifty-five tuf A barcodes to resolve eight species. Tuf A marker exhibited 6.1%–21.8% interspecific divergences, wider than the gap of rbc L exon 1,3.5%–11.5%. Molecular analysis of rbc L exon 1 sequences of Codium revealed eight distinct species like tuf A analysis separated in five phylogenetic groups. DNA barcoding of the genus Codium using tuf A marker is more helpful to overcome the limit of morphological identification, and this is more potential to reveal cryptic species and to resolve the relationships among subspecies than rbc L analysis alone. The complement of tuf A barcoding and rbc L analyses including morphology for the genus Codium in the northwestern Pacific will give much more reliable achievement for discovering species diversity and resolving the phylogenetic relationships.  相似文献   

3.
Three specimens of the serranid fish(Serranidae), Plectranthias kamii Randall, 1980 were collected from fish market, Bitung, North Sulawesi on May and June 2010. Some morphological characters P. kamii is closely related to P. sheni, P. megalophthalmus, P. retrofasciatus, P. rubrifasciatus, P. knappi, P. helenae, P. pelicieri, P. jothyi, P.retrofasciatus and P. randalli in sharing of body width, upper jaw length, pelvic spine length and orbit diameter.Meristic count characters of P. kamii differ from P. sheni, P. pilicieri, P. megalophthalmus, P. retrofasciatus and P.rubrifasciatus in having more numerous dorsal spine(18 vs. 15–17) and below lateral line(33–34 vs. 29–33) and differ from P. megalophthalmus and P. rubrifasciatus in having more numerous pored scales in lateral line(13 vs.14–15) and shorter of anal spine. The present anthiine fish collected from Bitung, Indonesia was described as new record and bringing the total number of species of this genus known in Indonesia to seven.  相似文献   

4.
Aequorea taiwanensis, a new hydrozoan species from the Taiwan Strait was described using morphological and molecular characteristics. Both morphological and mitochondrial cytochrome oxidase subunit I (mtCOI) data supported A. taiwanensis n. sp. as a valid species. Sequence divergence and genetic distance of A. taiwanensis n. sp., A. papillata and A. conica were analysed based on the mtCOI gene sequences. The mtCOI sequences from these three species of the genus Aequorea showed high variation frequency, with sequence divergences ranging from 9.10% to 11.9%, and pairwise genetic distances ranging from 0.097 to 0.130. MtCOI sequence analysis provided diagnostic molecular systematic characteristics for accurate identification and discrimination of the species of Aequorea or their populations, and will be used to resolve evolutionary relationships among them.It was suggested that 10%—20% pairwise mtCOI sequence differences indicated the specieslevel divergence among congeneric species in the Hydromedusae.  相似文献   

5.
Feng  Zhi-yong  Tan  Guang-ming  Xia  Jun-qiang 《中国海洋工程》2019,33(2):207-218
Sediment transport capacity is a fundamental parameter in sediment transport theory and its accurate calculation is important from both theoretical and engineering viewpoints. The capacity of sediment transport has been studied extensively by many researchers in the last decades. Nevertheless, the underlying mechanism behind sediment transport capacity in estuaries remains poorly understood. The current study aims to explore the impact of the river–tide interaction on sediment transport and establish a formula of sediment transport capacity under the river–tide interaction. The impact of the river–tide interaction on the hydrodynamics and sediment dynamics in the Changjiang Estuary was analyzed, a practical method for describing the variation in tide-runoff ratio was established,and a formula of sediment transport capacity considering the impact of river–tide interaction was proposed by introducing the tide-runoff ratio. The new method bridged the gap between two well-known sediment transport capacity methods by considering the variation in the index a for the gravitational term and overcomes the drawback of distinguishing flood/dry season or spring/ebb tide in the calculation of estuarine sediment transport. A large amount of flow and sediment data obtained from the Changjiang Estuary were collected to verify the proposed formula. The effect of salt-fresh water mixture and the morphological evolution on sediment transport capacity of the Changjiang Estuary were discussed.  相似文献   

6.
The so-called zebra sole includes a group of small flatfishes characterized by transverse band pairs on the ocular side and distributed throughout shallow waters along the coast of the Indo-West Pacific Ocean. Sev-eral species of the zebra sole have been recorded from the coastal waters of China. Morphological analysis of 1 107 specimens of the zebra sole from 15 successive localities along the China’s coast demonstrated that no significant variations among these localities were found on the basis of meristic counts and morphometric characters. Phylogenetic analysis based onCOI gene sequences of 14 individuals and D-loop of 22 indi-viduals from eight localities showed that they were indistinguishable among these localities. Therefore, both morphological and molecular evidence supported the occurrence of a single species of the zebra sole along the China’s coast. The available name for this species isZebriaszebrinus (Temminck and Schlegel, 1846) in-stead ofZ.zebra (Bloch, 1787).Zebrias fasciatus(Basilewsky, 1855) andSolea ommatura (Richardson, 1846) are considered here as two synonyms ofZ. zebrinus.  相似文献   

7.
This report based on the results of investigations conducted in June 2007 and July 2008, respectively, on the benthic community structure and characteristic diversity of the Huanghai Sea (Yellow Sea) Cold Water Mass, as well as that in July 1959 during the national oceanic survey. The Naticidae specimens collected from Cold Water Mass in middle and northern Huanghai Sea were studied through morphological classiˉcation and the internal anatomy on radula. Three new species of Naticidae, i.e., Cryptonatica purpurfunda sp. nov., Cryptonatica sphaera sp. nov., and Cryptonatica striatica sp. nov. were identiˉed. The morphological characteristics of the new species are described, and the similarties and di?erences between the new species and similar species are compared and discussed.  相似文献   

8.
The ribosomal DNA internal transcribed spacer (ITS) region is a useful genomic region for understanding evolutionary and genetic relationships. In the current study, the molecular phylogenetic analysis of Pectinidae (Mollusca: Bivalvia) was performed using the nucleotide sequences of the nuclear ITS region in nine species of this family. The sequences were obtained from the scallop species Argopecten irradians, Mizuhopecten yessoensis, Amusium pleuronectes and Mimachlamys nobilis, and compared with the published sequences of Aequipecten opercularis, Chlamys farreri, C. distorta, M. varia, Pecten maximus, and an outgroup species Perna viridis. The molecular phylogenetic tree was constructed by the neighbor-joining and maximum parsimony methods. Phylogenetic analysis based on ITS1, ITS2, or their combination always yielded trees of similar topology. The results support the morphological classifications of bivalve and are nearly consistent with classification of two subfamilies (Chlamydinae and Pectininae) formulated by Waller. However, A. irradians, together with A. opercularis made up of genera Amusium, evidences that they may belong to the subfamily Pectinidae. The data are incompatible with the conclusion of Waller who placed them in Chlamydinae by morphological characteristics. These results provide new insights into the evolutionary relationships among scallop species and contribute to the improvement of existing classification systems.  相似文献   

9.
Abstract-The growth rate of the hyalid amphipod Hyale perieri was studied on the bases of Ikeda'sgrowth model which is based on the inter moult period (IP) and moult increament (ΔBL). To applythis approach, laboratory experiments were carried out at three temperatures regimes (15℃, 20℃,25℃) to gain accurate data of IP and BL. The total number of specimens used in this study was 86 at15℃, 24 at 20℃ and 70 at 25℃. The number of flagellar segments of both antennae of the Hyaleperieri could not be used as an index of growth (instar criterion). The obtained results indicated that,the predicted IP of the specimens was inversely related to temperature and in good agreement with theobserved values at the experimental temperatures. IP data obtained from laboratory-reared specimes arecombined with ΔBL data to establish a growth model for Hyale perieri from its release from the mar-supium (1.64 mm BL) to the maximum size (12.67 mm BL) as a function of temperature. The maxi-mum numbers of consecutive moults  相似文献   

10.
The identification of scallop larvae is essential to understand the population structure and community dynamics and to assess the potential environmental impacts caused by scallop larvae released or escaped. However, the larvae identification by morphological characteristics is notoriously difficult, mainly due to the small size (usually being less than 150 μm) and vague morphological characteristics among different scallop species. A simple and accurate molecular method was developed to identify four economically farmed scallop species, the Zhikong scallop Chlamys farreri, the noble scallop C. nobilis, the bay scallop Argopecten irradians and the Yesso scallop Mizuhopecten yessoensis. The tests used the high degree of species-specific microsatellite markers, which was specified by transferability analyses, assessed by reference individuals and evaluated by BLAST searches. The sensitivity test indicated that the species-specific microsatellites were sensitive enough for the detection of 1% -2% larvae in mixed plankton samples. Larvae collected from scallop hatcheries and their effluents and from the artificially controlled crosses were well identified to the species/hybrid level. The results demonstrated that the one-step PCR-based assay was technically simple, inexpensive and robust in identification analyses, and also less sensitive to initial quality of template DNA extracted from the ethanol-preserved samples for several years.  相似文献   

11.
Larval specimens ofHalicampus punctatus were collected off Ulsan and Uljin in December 2002 (three specimens) and off Ulsan in December 2003 (one specimen). These specimens are characterized by the following morphological characteristics: rings, 14 + 35 = 49; subdorsal rings, 1 + 3 = 4; dorsal fin rays, 19 – 20; pectoral fin rays, 14 – 15; anal fin rays, 9; head length (HL), 5.8 – 6.7 in the standard length; snout length, 1.9 in HL; snout depth, 3.7 – 5.2 in snout length. The number of caudal fin rays 9 is less than those of the other species in the same genus 10. Wide stripe bands composed of small pigments are shown in the trunk and the tail. Melanophores are not found in the dorsal fin, the pectoral fin, and the anal fin except the caudal fin. The supraoccipital crest is on the head. The frontal ridge is on the dorsal side of front trunk. The blanched ridges on the opercular are fused with a main ridge like a tree branch. A few branched ridges that are small and narrow on the trunk and the tail are fused with the main ridges. We report these specimens as the first record in Korea and name them ‘Byeol-silgo-ki’ in Korean.  相似文献   

12.
2015年10月中旬,在浙江省舟山市近海的渔业资源调查中采集到天竺鲷标本,经鉴定发现其中黑边银口天竺鲷为浙江新纪录种。本文对采集的6尾黑边银口天竺鲷标本拍摄照片并开展形态特征和DNA条形码研究,对该种的拉丁学名进行校正。黑边银口天竺鲷的有效学名为Jaydia truncata(Bleeker,1854)。具有以下主要形态特征:背鳍鳍条数VII+I,9,胸鳍鳍条数16—17;背前鳞数4;第一鳃弓总鳃耙数3—4+11—13,发达鳃耙数1+9—10,角鳃弓上的鳃耙数9;前鳃盖骨边缘锯齿状;第一背鳍上端黑色,第二背鳍及尾鳍边缘黑色,第二背鳍与臀鳍中部各具一黑色纵纹。本研究分析了浙江海域5种天竺鲷科鱼类的形态差异,并编制了检索表。测定了6尾标本的DNA条形码,结合Gen Bank中所有学名为Jaydia truncata及其同种异名的同源序列分析,发现所有个体明显分为两个分支,且两者遗传距离达到0.149,表明两分支可能为不同的有效种,Gen Bank中只有AB890050和JQ681488与本研究序列结果相近。  相似文献   

13.
本研究报道了在福建省晋江和厦门近海采集到的新记录种——中国鱚,将其分布区向南延伸至福建省沿海,并对采集到的中国鱚进行形态特征的重新描述,及扩增其DNA条形码.中国鱚的主要鉴别特征为:第一背鳍鳍膜具不规则的、呈弥散状的黑色斑点,由前往后逐渐稀疏;第二背鳍沿鳍条具3~4行规则的黑色斑点;侧线上鳞数为6~7;脊椎骨数为37~39.结合Gen Bank中鱚属鱼类的同源序列进行比对研究,结果显示本研究采集到的中国鱚与中国鱚模式种聚类到一起,并与其余种类明显分开,在遗传距离和氨基酸水平上与其他种类产生了明显地分化,进一步证明了DNA条形码能高效快速的鉴别鱚属鱼类.本研究为鱚属鱼类分类与研究提供理论基础,通过调查发现中国鱚主要分布在有大量淡水注入的河口区,南至韩国光阳沿海,北至中国福建省沿海,数量较少并不能形成渔汛.  相似文献   

14.
孙静  黄勇 《海洋科学》2016,40(9):39-44
海洋线虫是海洋底栖生物中数量上最丰富的类群,在海洋生态系统中起着重要的作用。对海洋线虫进行种类鉴定是线虫研究中最重要的工作之一。目前,海洋线虫的鉴定主要采用形态学的分析方法,但是这种方法往往费时费力,对于如此丰富的物种,急需新的鉴定方法。作者以黄海潮间带自由生活线虫优势种——中华钩线虫(Oncholaimus sinensis)为例,在形态学分类的基础上,将DNA条形码技术引入线虫的鉴定中,探讨了线粒体细胞色素C氧化酶第一亚基(mt COI)基因序列、28S r DNA序列的D2D3区以及18S r DNA序列的部分序列作为DNA条形码在中华钩线虫中的适用性。结果表明,18S r DNA序列可作为该种线虫的DNA条形码,为海洋线虫的DNA条形码研究提供了很好的借鉴。目前,利用DNA条形码技术对海洋线虫进行鉴定的报道在国内还属空白,本研究将是海洋线虫分类学研究的很好补充。同时,对于了解该海域海洋线虫多样性及群落分布格局,开展海洋环境监测,进而对海洋的底质环境状况进行健康评价具有十分重要的科学意义。  相似文献   

15.
北部湾出现苏门答腊金线鱼及其形态特征   总被引:3,自引:1,他引:2  
黄梓荣  王跃中 《台湾海峡》2009,28(4):516-519
2008年1月在北部湾调查时,采集到1金线鱼科标本,经鉴定为苏门答腊金线鱼.渔获总尾数156尾,带回5尾到实验室作进一步鉴定,标本现保存在南海水产研究所标本馆.体长范围为50mm-126mm,背鳍X-9;臀鳍Ⅲ-7;胸鳍15;腹鳍I-5;尾鳍21.体适度延长,侧扁,体长为体高的3.5~3.8倍,体高在躯干中部背鳍第七鳍棘处为最高.上下颌几等长,仅上颌前端具较大犬牙.眼眶下缘处于吻端与胸鳍基部上端连线的上方,眼眶下缘顶端微凹,后缘几呈直线.前鳃盖骨裸露(无鳞)宽度是有鳞宽度的1.4~1.7倍.体被薄栉鳞,背鳍与侧线间具鳞4~7行,有腋鳞.侧线完全,位高,近似与背缘平行.眼下至上颌骨呈倾钭的金黄色带,体上部略带桃色,下部银白色,体侧有明显的金黄色带,并延至尾鳍叉端附近鳍条.体侧有一红斑,红斑位于背鳍起点与胸鳍基部之间的侧线下缘.背鳍边缘黄色,中间有明显的黄色带,臀鳍粉红色并有2条黄色带,尾鳍粉红色,近叉端鳍条呈金黄色.背鳍第一鳍棘与第二鳍棘由隔膜分开,第一鳍棘和第二鳍棘其长度短于其他鳍棘,无丝状延长.背鳍鳍棘部与鳍条部连接完全,中间无缺刻.胸鳍伸达肛门上方,胸鳍长度为头长的1.1~1.5倍.腹鳍中等长,约与胸鳍等长,不伸达臂鳍起点.臂鳍最后鳍条不明显长于其他鳍条.尾鳍呈叉形,上叶末端呈锐角或钝圆,上叶末端略呈丝状延长或延长不明显.  相似文献   

16.
基于cox1片段序列的DNA条形码为浮游动物种类鉴定提供了新的可靠手段,构建了胶州湾网采浮游动物DNA条形码文库,在国内首次使用宏遗传组学方法研究夏季胶州湾海洋浮游动物的群落组成。共获得环境样品DNA条形码149条;以6%为阈值共检出37个OUT,其中19个与DNA条形码数据库中序列程度非常高(〉97%),可以鉴定到种...  相似文献   

17.
本研究采集中国沿海常见五种鲳属鱼类并对其耳石进行系统的多元形态学描述与比较。耳石形态在整体轮廓、边缘以及前部表现出明显的种间差异,展现了耳石形态的种内特异性。随着基因隔离与种间分化,鲳属鱼类耳石也逐渐变薄且基叶、翼叶更为发达。上述观察到的种间耳石形态差异与鱼体本身生活的水层以及温度联系紧密。96.6%的判别成功率也证明鲳属鱼类耳石显著的种间差异,表明形态学方法可以作为鲳属鉴别的有效手段之一。  相似文献   

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