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1.
Thirteen new species of benthic calanoid copepods are described from depths of 1,184–1,697 m off New Zealand. Seven species belong to previously described aetideid genera (Bradyidius—four spp., Comantenna—one sp., Pseudeuchaeta—two spp.) and the remainder represent new genera in three families: Aetideidae—three genera, four spp.; Arietellidae—one genus and sp.; Bathypontiidae—one genus and sp.  相似文献   

2.
The genus Euaetideus Sars, 1925 is here merged with Aetideus Brady, 1883 (Copepoda : Calanoida : Aetideidae). Three new species of the genus Aetideus are described from the Pacific as well as the males of three other known species. A key is given to the known males and females in the genus Aetideus. The closely related genera Paivella and Snelliaetideus are compared with Aetideus.  相似文献   

3.
长臂虾科(Caridea:Palaemonidae)是真虾类中最大的科级单元之一,为了探索长臂虾科内部的系统演化关系,作者采用从Genbank中下载的长臂虾科两亚科(Palaemoninae,Pontoniinae)14属30种长臂虾的线粒体16s rRNA基因序列片段,以鼓虾科(Alpheidae)细足鼓虾(Alpheus gracilipes)为外群分析长臂虾亚科和隐虾亚科之间的系统发育关系。在获得的466个序列位点中,变异位点263个,简约信息位点213个。DNA序列分析显示,隐虾亚科的德曼隐虾属(Manipontonia)与长臂虾亚科的遗传距离(0.211)要小于其与所在亚科的遗传距离(0.245);此属在基于贝叶斯法(BI)和邻接法(NJ)构建的系统发育树中也与长臂虾亚科的种属聚合为一支,然后与隐虾亚科种属聚合的一支成为姊妹群。结合此属与长臂虾亚科尾瘦虾属(Urocaridella)形态相似的特征,建议对德曼隐虾属在长臂虾科中的分类地位进行重新评估。除隐虾亚科德曼隐虾属聚合到长臂虾亚科聚类簇外,两亚科所属的其他种属各自聚合为一支,在系统树中互为姊妹群,支持将长臂虾分为两亚科的分类系统。  相似文献   

4.
福建漳江口红树林保护区浮游植物群落的季节变化研究   总被引:4,自引:1,他引:3  
于2001年1月~2003年1月对福建省漳江口红树林区水体浮游植物群落的季节变化进行了研究。结果表明,漳江口红树林区浮游植物以硅藻门种类为主,优势种为长菱形藻(Nitzschia longissima)和菱形藻(Nitzschia sp.1)等,同时出现多种裸藻、绿藻和甲藻。本次调查共鉴定到浮游植物31属87种(包括变种),其中硅藻门23属75种(包括变种),蓝藻门3属3种,绿藻门1属4种,金藻门1属1种,甲藻门2属2种,裸藻门1属2种。浮游植物密度变化范围为2.78×104~1.14×106个/L,平均为3.51×105个/L,季节变化为双峰型。出现大量的底栖硅藻和淡水性藻类是该水域浮游植物的一个特点。浮游植物的组成和结构表明该水域水质较好。  相似文献   

5.
通过nlsrDNA(nuclear large-subunit ribosomal DNA)及nssrDNA(nuclear small-subunit ribosomal DNA)的PCR-RFLP研究广东徐闻地区8科15属25种62个造礁石珊瑚样本的共生藻。结果表明,共生藻nlsrDNA的RsaI酶切基因型只存在一种,属于C系群共生藻;而nssrDNA的MobⅠ和TaqⅠ两种酶切都存在两种基因型。实验进一步通过PCR直接测序法得到62个造礁石珊瑚样品的共生藻ITS序列,与GenBank上的4种虫黄藻ITS序列构建Neighbor-Joining系统发育树,结果表明该区的造礁石珊瑚共生两种不同种类(亚系群)的共生藻,分别为C1亚系群与C15亚系群共生藻,两个亚系群间的遗传距离为0.019。广东徐闻地区造礁石珊瑚共生藻多样性偏低,暗示该地区珊瑚礁生态系统应对环境变化的能力可能较弱。  相似文献   

6.
Morphology and distribution of nineteen New Zealand Recent species of Foraminifera of the families Islandiellidae and Cassidulinidae are discussed. One new genus, Evolvocassidulina, and four new species, Favocassidulina australis, Globocassidulina canalisuturata, Globocassidulina spherica, and Ehrenbergina carinata, are described and figured. The use of radial and granular wall structure as a fundamental character in classification is supported by its uniformity in individual genera and species.  相似文献   

7.
海胆的叉棘是海胆御敌、清除体表异物的重要器官,其形状在海胆的分类上具有重要意义。本文通过扫描电子显微镜对西太平洋海山区柔海胆科软海胆属Araeosoma、兜海胆属Sperosoma和革海胆属Hygrosoma的叉棘形态与结构特征进行研究,并提供了柔海胆科属的检索表。结果表明:柔海胆有三种常见的叉棘形式,三叉叉棘、三叶叉棘和指状叉棘。三叉叉棘和三叶叉棘在3个属中均存在,指状叉棘只在软海胆属中存在,三叶叉棘和指状叉棘的超微结构变化比较细微,三叉叉棘的超微结构特征具有明显的种属间差异。建议将叉棘的种类和结构作为柔海胆科的分类依据。  相似文献   

8.
Pseudocycnus appendiculatus Heller is described and recorded, for the first time from New Zealand, on Thunnus alalunga (Bonnaterre, 1788). Pseudocycnus spinosus Pearse, 1951 and P. thynnus Brandes, 1955 are thought to be synonyms of P. appendiculatus. Other species previously placed in the genus are discussed and the action of Yamaguti (1963) in removing them to other genera supported. It is suggested that the family Pseudocycnidae Yamaguti, 1963 cannot be differentiated from the family Dichelesthiidae Bassett‐Smith, 1898.  相似文献   

9.
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   

10.
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   

11.
于1993年7月-1995年7月,基于隐虾亚科绝大部分属的分类学,系统学、比较形态学研究及部分生物学文献资料并对17个属的标本进行解剖分析,以支序分析地隐虾亚科作了系统发育初步探讨。结果表明,隐虾亚科为一单系类群,起源于原始的行自由生活的长臂虾类祖先,该类群因躲避敌害而在石珊瑚形成的小空间中营隐蔽生活,逐渐发展到可与腔肠动物、棘皮动物、海绵动物、双壳类软体动物等营共栖生活与海绵动物和双壳类共栖才可  相似文献   

12.
Ceuthonoe, a new genus with type species C. nezhai sp. n. commensal with euplectellid glass sponge (Hexactinellida: Euplectellidae), is described and illustrated, based on the material collected from Weijia Guyot, western Pacific. The new genus is distinguished by a combination of characters: body with 32 segments; 14 pairs of elytra; prostomium with prominent cephalic peaks and facial tubercle; aciculae and chaetae on tentaculophores; biramous parapodium, each ramus with a long aciculum penetrating epidermis, without supra-or subacicular process; and noto- and neurochaetae with unidentate tips. Ceuthonoe gen. n. is mostly silimar to genera of Polynoinae in morphology. However the phylogenetic analysis based on cytochrome c oxidase subunit I, 16S, 18S, and 28S genes suggested that this new genus was separated from the main branch of Polynoinae. The study also discussed the genera related to the new genus.  相似文献   

13.
The sea anemones Calliactis conchicola Parry, 1952 and Paracalliactis rosea n.sp. are described. This is the first report of the hormathiid genus Paracalliactis for New Zealand. Calliactis conchicola occurs with living gastropods, hermit crabs, and a true crab, and Paracalliactis rosea occurs with hermit crabs and a true crab. Certain characteristics of each of the two anemones suggest that the genera Calliactis and Paracalliactis may not be as discrete as was indicated by earlier reports.  相似文献   

14.
九龙江口红树林土壤微生物的类群及抗菌活性   总被引:21,自引:2,他引:19  
研究了九龙江口的秋茄(Kandelia candel)林和白骨壤(Avicennia marina)林两个红树林群落及其相应对照光滩土壤微生物的类群及抗菌活性.对微生物类群的研究结果表明:九龙江口红树林区土壤细菌中,芽孢杆菌(Bacillus)是最占优势的属;放线菌以小单胞菌属(Micromonospora)最具优势;其次是链霉菌属(Streptomyces),从秋茄林到白骨壤林,由于潮位降低,小单胞菌比例增加,而链霉菌比例下降;丝状真菌以半知菌占绝对优势,木霉(Trichoderma)、曲霉(Aspergillus)和青霉(Penicillum)是最常见的属;随着土壤深度的增加,微生物的类群减少,但芽孢杆菌和小单胞菌的相对比例增加;红树林土壤微生物类群比对照光滩丰富,缘于林内土壤营养与微生物的栖息条件比光滩优越.对抗菌活性研究表明:土壤真菌的抗菌活性低,抗菌谱窄;放线菌的抗菌活性高,抗菌谱宽,具有抗菌活性的放线菌多为小单胞菌,小单胞菌是一类值得重视的放线菌.  相似文献   

15.
Despite the high number of species and ecological diversity of pandalid shrimps, there has been no previous attempt to resolve evolutionary relationships of several genera using molecular tools. Although mitochondrial DNA cytochrome oxidase I (COI) is widely used in barcoding studies to delimit species boundaries, additional insights into phylogenetic affinities can be obtained, especially when used in combination with data from additional genes. The knowledge of molecular diversity is essential to understand phylogenetic relationships and will help systematic clarifications. Based on partial fragments of the 16S and COI genes, we have focused specifically on addressing the systematic relationships of the economically and ecologically important shrimp genus Plesionika within a framework of five genera from within the Pandalidae. Our results showed that species within Plesionika are substantially divergent when compared with other genera, exhibiting the highest average nucleotide divergence, with 0.1123 and 0.0846 in COI and 16S genes, respectively. In addition, sequence divergence was found to vary greatly within the genus Plesionika (COI/16S): 0.0247/0.0016 between Plesionika antigai and Plesionika heterocarpus and 0.1616/0.098 between Plesionika heterocarpus and Plesionika edwardsii. We did not find amino acid sequence divergence between P. heterocarpus and P. antigai compared with P. heterocarpus and P. edwardsii (8.10%, K2P distance). Three species of Plesionika (P. antigai, P. heterocarpus and Plesionika scopifera) appear well separated from other Plesionika species in both maximum likelihood and Bayesian analyses. The present study confirms the utility of COI over 16S as a genetic marker to resolve relationships between different species of Plesionika from the Northeast Atlantic and Mediterranean Sea, in addition to species delimitation. The findings highlight the need to further review paraphyly within Plesionika in an attempt to recognize a concordance in the evolutionary history of Plesionika with major ecological and geological events.  相似文献   

16.
王琦  孙萍  辛明  张学雷  李艳 《海洋与湖沼》2023,3(3):732-746
东印度洋受到印尼贯穿流(Indonesian Throughflow,ITF)等多个大洋流系影响,是太平洋水在低纬度进入印度洋的重要通道,具有显著的生态效应,是金枪鱼的重要渔场之一。为了解上述海域浮游植物群落组成、时空特征及其影响因素,基于2020年1~2月在该海域采集到的浮游植物样品及同步的环境数据,对其种类组成、生态类型、细胞丰度、优势类群等群落组成及其与环境因子关系进行了研究,并与赤道东印度洋浮游植物群落进行了比较。结果表明:研究海域共鉴定浮游植物4门57属268种(含变种、变型),其中,硅藻38属129种,甲藻17属136种,金藻1属2种,蓝藻1属1种;生态类型以热带大洋性种类、大洋暖水种和热带近岸种为主,浮游植物区系属于热带-亚热带生物区系。细胞丰度介于1.28×103~7.84×104 cells/m3之间,平均值为1.55×104 cells/m3。优势种中硅藻占绝大多数,分别为短叉角毛藻(Chaetoceros messanensis)、伏氏海毛藻(Thalas...  相似文献   

17.
研究了热带西太平洋雅浦Y3海山冬季和马里亚纳M2海山春季网采浮游植物群落结构,对调查区浮游植物的物种组成、优势种类、细胞丰度以及多样性指数进行了分析。结果表明,两个海山区共鉴定浮游植物4门50属219种,其中硅藻门30属106种,甲藻门17属112种,蓝藻门1属2种,金藻门2属3种。两个航次研究区浮游植物优势种均以链状硅藻如根管藻(Rhizosolenia)、半管藻(Hemiaulus)和角毛藻(Chaetoceros)等属的种类为主,此外太阳漂流藻(Planktoniella sol)、铁氏束毛藻(Trichodesmium thiebautii)以及部分角藻(Ceratium)物种优势度也比较明显。Y3海山区浮游植物细胞丰度介于1.60~16.61 cells/L,平均值为5.02 cells/L; M2海山区浮游植物细胞丰度介于1.36~10.20 cells/L,平均值为4.12cells/L。两个海山区浮游植物细胞丰度的分布趋势均受硅藻影响较大,甲藻细胞丰度相对较低。在属的水平上,角毛藻、根管藻、角藻和半管藻等属的细胞丰度对两个海山区浮游植物总细胞丰度的贡献较大。多样性指数方面, Y3海山区浮游植物群落香农-威纳指数H′(shannon-wiener index)介于3.95~4.69,平均值为4.30; M2海山区浮游植物群落香农-威纳指数介于3.23~4.46,平均值为3.83。两个海山区浮游植物群落多样性指数均处于较高水平,但站位间的变化不明显。目前,关于热带西太平洋海山区浮游植物群落结构的研究还非常缺乏,亟需后续研究的补充。  相似文献   

18.
描述了采自东海陆架沉积物中自由生活线虫HopperiaNemanema属的两个新种。新种大化感器霍帕线虫主要特征是螺旋形化感器5圈,较大;弓形交接刺近端宽大具有中肋,延伸至三分之一处;引带具有弯曲的引带突;6个乳突状的肛前辅器;锥柱状尾具有膨大的末端和尾端刚毛。新种小线虫的主要特征是身体大小是属内最小的;具有较大的椭圆形化感器;尾锥状;交接刺细,具有腹面翼膜,近端弯钩状;引带环形;1个肛前辅器乳突状,其上着生3条刚毛。更新完善了Hopperia属17个种的二岐检索表。  相似文献   

19.
The muscle myogen proteins of 10 species of the family Galaxiidae exhibited a high degree of species specificity when separated by starch gel electrophoresis. Non‐diadromous, non‐lacustrine species had some variation in the proteins present, while diadromous and lacustrine species, except for Galaxias maculatus, had remarkably uniform muscle myogen electrophero‐grams. The variation can be explained by polymorphism and mosaic evolution of isolated freshwater populations. It was found that previously erected specific and generic categories, except for G. vulgaris, are clearly defined by differences in muscle protein. The standardised electropherogram types obtained were subjected to cluster analysis using both squared Euclidean distance and the complement of Jacard's coefficient with average sorting strategy. A principal component analysis was also carried out. The first two components of the principal component analysis widely spaced the three genera included in this study (Salmo, Galaxias, and Neochanna), with N. burrowsius occupying an intermediate position between Galaxias and Neochanna. Previous workers have considered this species to be a connecting link between the two genera. The dendrogram produced by using squared Euclidean distance (which included all available information) first clustered the types into Salmoniidae and Galaxiidae. The latter were split into the genus Neochanna and the genus Galaxias which was then subdivided into stout‐bodied species (G. argenleus and G. jasciatus) and slender‐bodied species. G. brevipinnis and G. vulgaris types were further separated from the three alpine Galaxias species and G. maculatus. The substantial agreement of these results with previous taxonomic efforts indicates that electrophoretic data can be a valid taxonomic tool.  相似文献   

20.
采用分子生物学方法,对分离的米氏凯伦藻4株藻际异养细菌进行分子鉴定和功能分析。结果表明,经16S rRNA序列分析,4株藻际异养细菌分别隶属于Formosa、Erythrobacter、Shewanella和Marinobacter四个属,P1菌株与Formosa的16S rRNA核苷酸序列的同源性为95%,P2、P3和P4菌株与Erythrobacter、Shewanella和Marinobacter的同源性在99%以上。通过4株异养细菌及其同源性大的24株细菌构建进化树得出,28株细菌在系统发育树中主要分成4个分支,与同源性分析相符。  相似文献   

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