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1.
Epizoic diatoms on marine copepods are common in nature and may have a special ecological relationship with their hosts.However,this special ecological group is not well known,and it has only rarely been studied in the China seas.To address this knowledge gap,the species diversity and classification of epizoic diatoms on planktonic copepods were studied with samples collected from the East China Sea.In the present study,a marine araphid diatom genus Protoraphis and its type species,Pr.hustedtiana,were observed and identified by light and electron microscopy,thus representing the first record of this genus and its type species in China.This genus is characterized by a median sternum strongly bent to opposite sides and terminate in two transapical grooves at the valve ends.Protoraphis hustedtiana was found to be epizoic on the posterior body appendages and segments of the marine calanoid copepod Candacia bradyi.An internal view shows a complex,ear-shaped process that is close to the apical slit field.The ecological habitats and geographical distributions of Protoraphis were also discussed,and,together with complementary morphological studies,our results have increased the number of records for marine epizoic diatoms to three genera with three species in China,including Pseudohimantidium and Pseudofalcula.  相似文献   

2.
Two new species of Naticidae ( Mollusca, Gastropoda) collected from the coast of China are described: Cryptonaitca huanghaien- s/s sp. nov. and Sinum vittatum sp. nov. The morphological characteristics between the new species were described and the related information was provided. The similarities and differences between the new species and related species were also compared and discussed. The new species Cryptonaitca huanghaiensis differed from Cryptonaitca hirasei and Cryptonaitca andoi in outer shape, operculum and radula. The new species Sinum vittatum is similar to Sinumjaponicum (Lischke, 1869), but the shell of the former is flat-elliptical in shape, spire very small, slightly convex. While the latter is flat-globular in shape, apex light brown in color, without a brown band on the body whorl. The comparison results revealed that Cryptonaitca huanghaiensis and Sinum vittatum were two new species from the coast of China. Specimens studied were obtained from collections in the Marine Biological Museum, Chinese Academy of Sciences.  相似文献   

3.
One new species of free-living marine nematodes Enoplus taipingensis sp.nov.from the rocky intertidal seaweeds in the Taiping Bay,Qingdao is described and illustrated with scanning electron microscopy observation and 18S rRNA gene sequence analysis.Enoplus taipingensis is characterized by special arrangement of lateral setae on the tail,three cervical setae,distal structure on the supplement,and much longer body length with bigger De Man ratio "a".Type specimens are deposited in the College of Marine Life Science,Ocean University of China.  相似文献   

4.
Euniphysa, originally a genus of the family Eunicidae, was erected by Wesenberg-Lund in 1949, and for a longtime there has been only one species in this genus. The present report is based on our samples collected from the South China Sea, and we consider that the differences between Euniphysa and Eunice are very significant: Five occipital tentacles distributed unequidistantly; the jaw consists of 6 pairs of maxillary plates; the body may be divided into anterior region and posterior region, etc. Therefore we suggest that Euniphysa should be separated from Eunicidae, and become a new family Euniphysi-dae. At present this family includes 3 genera, namely, Euniphysa , Paraeuniphysa and 1 new genira Heterophysa; Totally there are 7 species, including 3 new species and 1 new combination species.  相似文献   

5.
The present paper is a report on the feeding habits, seasonal variations of food contents and feeding intensity, and the relationships between the digestive organs and feeding habits of Red-fin pargo, Parargyrops edita (from 39 to 178 mm in body length), collected from South Fujian and Taiwan Bank fishing ground. The result shows that Red-fin pargo is a demersal fish with wide range of food items of which are chiefly benthos and secondly nekton and plankton. Polychaeta, Ophiuroi-dea, Gammaridea, Pisces, Macrura, Ostracoda, Cephalopoda and Mysidacea are important food for both young and adult. The composition of food items varies with seasons. The feeding habits of the fish over 39 mm in body length do not vary with its age, but the adult take more Pisces and Cephalopoda than the young. The feeding intensity is the highest in spring and the lowest during winter. The feeding behavior is also closely related to its reproductive activity and the digestive organs are found to be adapted to its euryphagy.  相似文献   

6.
Ecological adaptation and ecological groups of pelagic ostracods were examined in the East China Sea (23°30′-33°00′N, 118°30′ -128°00′E), in relation to temperature and salinity. The data were collected in four surveys conducted from 1997 to 2000. The density, yield density, or negative exponent models were used to determine the optimal temperature and salinity of water for the thriving growth of pelagic ostracods. Thereafter, ecological groups and potential distribution patterns of pelagic ostracods were determined based on the predicted parameters such as optimal temperature and salinity, consulting the geographic distribution. The analytical results indicate that, among the numerical dominant pelagic ostracods in the East China Sea (ECS), Euconchoecia aculeata, E. elongata, E. chierchiae, E. maimai, and Cypridina dentata, etc. are offshore subtropical water species. These species are widely distributed in the area, and they can be brought by the warm current to north offshore during spring and winter. The predicated optimal temperature (OT) and optimal salinity (OS) for Paraconchoecia decipiens, P. echinata, P. spini- fera, P. oblonga, Conchoecia magna and Porroeciaporrecta are all greater than 25℃ and 34 separately. These species are mainly distributed in the waters of the Kuroshio, the Taiwan Warm Current, and the Taiwan Strait, and therefore are designated as ocean- ic tropical water species. On the other hand, Pseudoconchoecia concerttrica is considered as offshore subtropical water species based on its geographical distribution although its OT is 19℃. The other species, though their OSs are approximately 34 and with OTs ranging from 20° to 25℃, are considered as offshore subtropical water species because they were found to be widely distributed from the South China Sea to the East China Sea.  相似文献   

7.
Along with the sequencing technology development and continual enthusiasm of researchers on the mitochondrial genomes, the number of metazoan mitochondrial genomes reported has a tremendous growth in the past decades. Phylomitogenomics—reconstruction of phylogenetic relationships based on mitochondrial genomic data—is now possible across large animal groups. Crustaceans in the class Malacostraca display a high diversity of body forms and include large number of ecologically and commercially important species. In this study, comprehensive and systematic analyses of the phylogenetic relationships within Malacostraca were conducted based on 86 mitochondrial genomes available from Gen Bank. Among 86 malacostracan mitochondrial genomes, 54 species have identical major gene arrangement(excluding t RNAs) to pancrustacean ground pattern,including six species from Stomatopoda, three species from Amphipoda, two krill, seven species from Dendrobranchiata(Decapoda), and 36 species from Pleocyemata(Decapoda). However, the other 32 mitochondrial genomes reported exhibit major gene rearrangements. Phylogenies based on Bayesian analyses of nucleotide sequences of the protein-coding genes produced a robust tree with 100% posterior probability at almost all nodes. The results indicate that Amphipoda and Isopoda cluster together(Edriophthalma)(BPP=100).Phylomitogenomic analyses strong support that Euphausiacea is nested within Decapoda, and closely related to Dendrobranchiata, which is also consistent with the evidence from developmental biology. Yet the taxonomic sampling of mitochondrial genome from Malacostraca is very biased to the order Decapoda, with no complete mitochondrial genomes reported from 11 of the 16 orders. Future researches on sequencing the mitochondrial genomes from a wide variety of malacostracans are necessary to further elucidate the phylogeny of this important group of animals. With the increase in mitochondrial genomes available, phylomitogenomics will emerge as an important component in the Tree of Life researches.  相似文献   

8.
A small armed dinoflagellate bloomed in the aquaculture ponds off the coast of Liaodong Bay, Bohai Sea of China,resulting in heavy mortalities of the cultured prawns(Penaeus japonicus) and larvae of Chinese mitten handed crabs(Eriocheir sinensis). The bloom-forming species was successfully isolated, and cellular morphology of the specimen was consequently investigated through light, fluorescent and electron microscopy. The small((14.4±1.6) μm in length) ellipsoid cells show typical Heterocapsa thecal plate arrangement(Po, cp, 5′, 3 a, 7′′, 6 c,5 s, 5′′′, 2′′′′). The episome is evidently bigger than the hyposome. One to three spherical pyrenoids are located above or beside the large elongated nucleus. The body scale is characterized by a triangle basal plate with one central upright and nine peripheral spines. Above all, Heterocapsa bohaiensis could be distinguished from other Heterocapsa species by the combination of the cell size, morphology, cellular structure and body scale. Sequence analyses of both ITS and LSU regions reveal the significant genetic divergence between H. bohaiensis and other established species in this genus, further supporting novelty of this species. Noticeably, different sample treatment methods resulted in morphological variation of the apical pore complex(APC) of H. bohaiensis, which needs to be taken into account in future study.  相似文献   

9.
Among the specimens of Leptomysim (Crustacea, Mysidacea) collected from the northern part of the South China Sea by the Institute of Oceanology, Academia Siniea, Leptomysis xenops Tattersall and a closely related form were found by the authors. While studying on the morphological characteristics of these two species and their allies in the Tribe Leptomysini, we found that there are two natural groups of species previously ascribed to the genus Leptomysis G. O. Sars. The first group includes the type species of the genus and other 8 known species, viz. Leptomysis gracilis (G. O. Sars. 1864), L. lingvura (G. O. Sars, 1866), L. sardica G. O. Sars, 1877, L. mediterranea G O. Sars, 1877, L. capensis Illig, 1906. L. megalops Zimmer, 1915, L. australiensis Tattersall, 1927. L. peresi Bacescu, 1966, and L. burgii Bacescu, 1966, of which the cornea of the compound eye is normal——with numerous small facelets of equal size, the telson is usually armed with 2 or 3 pairs of larger apical spines; while in species of the second group, in which L. apiops apgops G. O. Sars, 1877, L. apiops banyulensis Bacescu, 1966, L. xenops Tattersall. 1922 and the new species described in this paper are included, the cornea consists of two parts, the anterior part with small and normal faeelets, but of the posterior part, the facelets are very unique, being larger and much elong ted to form a "bauquet"-shaped process. These differences showed that the two groups are heterogenous and belongs actually to two distinct genera. In order to receive the last 4 forms, a new genus, Paraleptomysis gen. nov. is established, and an account of the new genus and Chinese species is given in this paper. The type materials of the new species, P. sinensis sp. nov. are kept in the Institute of Oceanology, Academia Sinica (Qingdao).  相似文献   

10.
The fragments of 350 bp in 28S rRNA from the closely related monogenea of trematoda, Neobenedenia girellae and N. melleni are obtained by polymerase chain reaction (PCR) amplified using a couple of special primers and then sequenced. The results show that the comparison of 28S rRNA sequences, with only a base varying in 337 bp accounting for 0.3% genetic difference, from the relative species N. girellae and N. melleni parasitized on the different fishes in different farms displays that they possess a very high genetic similarity of 99.7%, higher than that of 99.41% for the single species N. melleni sampled in different areas, and the intraspecific divergence of N.melleni is 0.59%. Meanwhile, the interspecific differences between the two Neobenedenia and three Benedenia (i.e., B. lutjani, B. rohdei and B. seriolae) range from 2.08% tol 1.73%. In addition, UPGMA and MP molecular phylogenetic trees are constructed and proved to be consistent with each other. Though the morphological characteristics and the results of genetic diversity for the two Neobenedenia show a high similarity, whether they belong to a single species or not are still undefined, and the more genes of them should be further investigated, in combination with the systematical and detailed morphological study.  相似文献   

11.
中蚓虫是小头虫科较为常见的属,中国海区的样品过去常被鉴定为加洲中蚓虫Mediomastus californiensis Hartman。本研究中,来自东南沿海四个不同海区的118条中蚓虫样品被鉴定为一个新的种类,在此给出具体描述。这个新种具有如下特征:(1)第1至9刚节表皮双环型,刚毛束位于体节中间位置,而后的刚节多环型,刚毛束位于体节后半部;(2)后腹区具有疣足突起;(3)前4个胸刚节仅具双羽型翅毛状刚毛,其它体节仅具巾钩刚毛;(4)胸区巾钩刚毛的柄长且直,巾长为宽的3至5倍;(5)腹区巾钩刚毛不同于胸区,较短且具收缩部;(6)甲基绿染色模式独特。这个研究表明了中国海区的中蚓虫可能被误鉴定为加洲中蚓虫,而这个新种M.chinensis sp.nov.在东南沿海广为分布。  相似文献   

12.
The dinoflagellate genus Margalefidinium has been split from Cochlodinium as a new genus recently and Margalefidinium fulvescens is one of the five Margalefidinium species. Margalefidinium fulvescens is toxic and has been reported from the coastal waters of USA, Canada, Mexico, China, Japan, Indonesia, Korea, Pakistan and Spain. Here we provide the morphological and phylogenetic characterization for an isolate of it from the Jiaozhou Bay, Qingdao, China. Our results showed that the vegetative cells were subspherical to ellipsoidal, 34–60 μm in length, and 19–41 μm in width. Both single cell forms and colonies in chains of 2, 4, or 8 cells were observed in cultures, but chain forms with 2 or 4 cells were observed more often in the field samples. The cingulum was rather deep, encircling the cell approximately twice, but the sulcus was rather narrow, surrounding the cell about one turn. The nucleus was spherical and located at the central epicone. The chloroplasts were granular, brownish, and scattered peripherally. An orange pigmented body also appeared in the epicone. The apical groove appeared vase-like as previously described. Under epi-fluorescence microscopy, a pumpkin-like structure was clearly observed, in which cells were embedded. Cells were observed to exit from the structure, which led us to a hypothesis that the structure may provide cells a shelter to avoid predation or to respond to other stresses. The phylogenetic analyses based on partial LSU rDNA sequences indicated that M. fulvescens from the Jiaozhou Bay was grouped with M. fulvescens populations from other origins and closely related to the clade of M. polykrikoides.Our morphological observations and phylogenetic analyses together confirmed the presence of M. fulvescens in China and our monitoring has also observed the species dominant in the dinoflagellate community of the Jiaozhou Bay in the early autumn of 2015, which alerted us to continually monitor this bloom-forming species in the region.  相似文献   

13.
腹壁纤毛虫是一种附着在浮游动物上的原生生物,尤其是附着在桡足类和甲壳类上的。而缘毛虫是可以以自由或寄生的形式在世界各沿海地区和港湾处被发现。本研究首次对东印度洋表层至200 m深海域的缘毛类纤毛虫以及其水平分布展开了研究。根据纤毛虫的形态、纤毛结构和茎的形态等的特征,在2014年4月10日至5月13日东印度洋航次的浮游生物拖网样品中鉴定出了五种富腹纤毛虫,海洋钟形虫Vorticella oceanica、交替聚缩虫Zoothamnium alternans、阿拉聚缩虫Zoothamnium alrasheidi、远洋聚缩虫Zoothamnium pelagicum和海洋聚缩虫Zoothamnium marinum。并通过光显微镜和扫描显微镜拍摄的照片,说明了其形态、尺寸和特征。研究结果表明,海洋钟形虫和远洋聚缩虫的分布与硅藻(如,密聚角毛藻Chaetoceros coarctatus)和桡足类(如,短角长腹剑水蚤Oithona brevicornis)等寄主有关,也包括甲藻(如,三角角藻Ceraitum tripose)周围的一些个体。这些附着纤毛虫的分布在东印度洋海域东南区以海洋钟形虫、远洋聚缩虫和海洋聚缩虫为主,而在孟加拉湾北部则有大量的阿拉聚缩虫。这种分布的变化可能是与寄主的分布有关,如桡足类(短角长腹剑水蚤)和硅藻(密聚角毛藻)的分布影响。  相似文献   

14.
创伤弧菌是一种可感染人类的河口病原菌。建立快速,特异而敏感的检测方法,有助于创伤弧菌感染的早期疾病诊断和及时治疗。本研究设计了针对vvhA基因的一系列引物(包括两对外部引物和两对内部引物),采用环介导等温扩增技术(LAMP)来检测创伤弧菌。结果显示,本方法的最适扩增温度是63℃,反应仅需35分钟。扩增产物不仅可以用含有DNA ladder的琼脂糖凝胶电泳检出,也可借助钙黄绿素直接肉眼观察。采用45株菌株检测该方法的特异性,其中所有创伤弧菌均被检出而其他菌株检测结果皆为阴性。本方法的敏感性是普通PCR扩增的100倍,同时利用该方法可以准确检测出所有的模拟样品、临床标本及环境样品。与其他已知方法比较,针对vvhA基因的介导等温扩增技术可以快速、简单、敏感及特异地鉴定创伤弧菌。  相似文献   

15.
双壳类适应性进化遗传基础尚未有大量研究。而生活在沿海潮间带和深海环境中的双壳贝类适应性进化的分子机制更鲜有报道。我们首次测序组装了潮间带生活的偏顶蛤Modiolus modiolus的转录组序列。同时与生活在深海热液冷泉喷口的偏顶蛤Bathymodiolus platifrons进行了比较转录组分析,阐明了这两个物种在不同环境中的适应性进化机制。M. modiolusB. platifrons的转录组组装共产生182,476和156,261个转录本,N50值分别为1,769和1,545。同时注释到27,868和23,588个基因。GO富集分析表明这些基因有相似的富集模式。两物种进化分析鉴定到10,245个直系同源基因,其中26个基因受到强烈正选择(Ka/Ks>1),12个基因受到中度正选择(0.5M. modiolus的转录组组装拼接序列,同时通过比较转录组学分析阐明了其与近缘物种B. platifrons的适应性进化机制。这为两个物种后续研究提供了序列资源和研究基础。  相似文献   

16.
本文描述了采自中国南海中南部花水母亚纲一新属四新种:南海宽管水母,新属、新种Laticanna nanhaiensis gen.nov. et sp.nov.,芽拟原帽水母,新种Protiaropsis gemmifera sp.nov.,南海潜水母,新种Merga nanhaiensis sp.nov.和顶室无球水母,新种Rhabdoon apiciloculus sp.nov.。编制了深帽水母科已知属分属检索表和拟帽水母属、潜水母属以及无球水母属已知种分种检索表。模式标本保存于中国水产科学研究院南海水产研究所。  相似文献   

17.
车轮虫是一类主要寄生于贝类和鱼类体表的缘毛类纤毛虫原生动物。本文对分别寄生于海洋贝类--虾夷扇贝Mizuhopecten yessoensis,半咸水鱼类--鲻鱼Mugil cephalus和双色鳗鲡Anguilla bicolor bicolor,以及淡水鱼类--光唇鱼Acrossocheilus fasciatus鳃表和体表的虾夷扇贝车轮虫Trichodina pectenis,亚卓车轮虫T.jadranica,急尖车轮虫T.acuta和喙状车轮虫T.rostrata,进行了详细的分类学研究。本文第一次报道了虾夷扇贝车轮虫的活体和蛋白银染色后特征,该虫体也是国内新记录种。其它三个车轮虫物种感染的鱼类,均属新纪录宿主。同时,也报道了这四种车轮虫对宿主的感染率和感染强度。  相似文献   

18.
根据在中国近海采集到的标本,描述多毛类环节动物一新种——中华竹节虫(Sabaco sinicus sp.nov.)。该物种标本在乌沙科夫等(1962)报道后一直被错误鉴定为钩齿短脊虫(Asychis gangeticus Fauvel,1932)。我们基于以下性状将该种描述为一新物种:项沟和前三个刚节具深棕色色素点;刚节4–6的腺体分布特征;肛前节无刚毛;肛漏斗喇叭状,背侧小叶呈扁盘状;具膝状的背刚毛、表面有或无螺旋刺毛带的细毛状背刚毛;腹刚毛为排成一列的鸟嘴状齿片刚毛。钩齿短脊虫和该新种的区别在于前者身体无色素点,肛板背侧小叶呈三角形。自1950s以来,该物种的分布区已经从长江口以南海区明显向北扩展。  相似文献   

19.
One strain of unicellular greenish algae embedded by mucilage was successfully isolated from equatorial area in the Indian Ocean. Microscopic observation, ultrastructure features and genetic identification confirmed that the strain was closely related to Cyanothece sp., which was a cyanobacteria species with great ecological significance.Cells were solitary with oval or bacilliform shapes. Diameters of this strain were relatively small, ranging from 2.5 to 6.5 μm on average. Ultrastructure of cells was simple. Thylakoids were arranged parietal and keritomized content were observed in the thylakoid region. Various electron-transparent granules with low electron-dense region as well as cyanophycin or glycogen granules-like organelle and carbonxysomes were also observed. For pigment composition, the dominant pigments were chlorophyll a, β-Carotene, Zeaxanthin and an unknown pigment, contributing 23.8%, 26.1%, 14.7% and 15.7% to total pigments respectively. The phylogenetic analysis of16 S rRNA gene and nif H gene confirmed that Strain EIO409 was closely related with Cyanothece sp..  相似文献   

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