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1.
Cricotopus van der Wulp and Paratrichocladius Santos Abreu are among the most common genera of Chironomidae found in fresh waters throughout New Zealand. Imago, pupa, and fourth (final) instar larva of Cricotopus hollyfordensis n. sp. are described, and the male imagines, pupae, and larvae of Cricotopus zealandicus Hutton and Para‐trichocladius pluriserialis Freeman are redescribed from new material. C. hollyfordensis n. sp. can be distinguished from other Cricotopus species by antennal ratio and absence of tibial and abdominal markings in the male imago; shape and form of the thoracic horn, distinctive abdominal spinule patterns and lateral setae in the pupa; and mentum and mandible characteristics in the larvae. The combination of tibial and abdominal markings of the male imago; thoracic horn and abdominal spinule patterns of the pupa; and mentum and mandible characteristics of the larva distinguish C. zealandicus from P. pluriserialis and all other New Zealand Cricotopus species. P. pluriserialis is distinguished from Cricotopus species by the presence of normal and erect dorsocentral setae in the adult; smooth thoracic horn and distinctive abdominal spinule patterns of the pupa; mentum and mandible characteristics, supra‐anal setae longer than 2–3 abdominal segment lengths, and abdominal setae simple, never in tufts, in the larva. C. hollyfordensis n. sp. has been recorded from a fast flowing mountain  相似文献   

2.
Vigtorniella flokati, a new species of polychaete worm associated with decaying whale remains, is described. Three separate V. flokati populations were sampled using submersibles: two associated with implanted gray whale carcasses in the San Diego Trough (1240 m depth) and the Santa Cruz Basin (1670 m) off California, and one from sperm whale and balaeanopterid bones implanted on the slope of Oahu, Hawaii at 1000 m. Extraordinarily large numbers of live specimens were observed and videotaped in situ using submersibles in the San Diego Trough and the Santa Cruz Basin. The populations on the carcass implanted for 4 months in San Diego Trough, and on the bones implanted for 2 years off Oahu, were composed only of small sized individuals (including juveniles). V. flokati most closely resembles the poorly known V. zaikai Kiseleva, 1992, described from the Black Sea. Forty-six morphological characters were used in a phylogenetic analysis of selected nereidiform polychaetes. The resulting most-parsimonious trees indicate sister taxon status between V. flokati and V. zaikai, and that this clade is sister to the putatively ancient polychaete clade Chrysopetalidae. Whale falls, which are intense point sources of organic enrichment at the deep-sea floor, pass through three successional stages. V. flokati appears to colonize the middle, “enrichment opportunist” stage, inhabiting organic-rich bones and sediments 4–24 months after carcass arrival. V. flokati exhibits remarkable behavior, clinging posteriorly to whale bones or nearby sediments to form a writhing carpet at densities exceeding 8000 m−2. Its extraordinary abundance on whale falls, and apparent absence from other habitats, suggests it to be a whale-fall specialist. The precise feeding mechanism of the worm remains unknown, but we hypothesize that it may utilize dissolved organic carbon derived from the organic-rich setting of whale falls. The widespread occurrence of V. flokati on ephemeral, food-rich habitat islands in the Pacific suggests life-history strategies analogous to those for hydrothermal-vent and cold-seep species.  相似文献   

3.
A few species in the genus Grateloupia (Halymeniaceae,Rhodophyta) have been investigated in detail with respect to morphological observations and molecular analyses.In this study,the authors document the vegetative and reproductive structures of two new species of Grateloupia,G.dalianensis H.W.Wang et D.Zhao,sp.nov.and G.yinggehaiensis H.W.Wang et R.X.Luan,sp.nov.They both have the morphological character that carpogonial ampullae and auxiliary cell ampullae are the simple Grateloupia-type.The two species can be distinguished from other species of the genus by their distinctive morphological features respectively.Based on ribulose-1,5-bisphosphate carboxylase/oxygenase (rbcL) gene sequences,the phylogenetic tree obtained in the study indicated that they are both embedded within the Grateloupia clade.G.dalianensis clusters a subclade with G.asiatica,and G.yinggehaiensis forms a single monophyletic subclade with G.hawaiiana.  相似文献   

4.
似三核线虫属的两个新种似三核线虫红树林种（Tripyloides mangrovensis n.sp.）和似三核线虫厦门种（Tripyloides amoyanus n.sp.）在本文中分别被描述,标本分别采自中国厦门同安湾红树林和海门岛红树林。两个新种都具有6根较粗的外唇刚毛,雄性标本不具有肛前附器,尾部圆锥圆柱形且不具有末端突起。似三核线虫红树林种（Tripyloides mangrovensis n.sp.）口器分成两部分,化感器圆形,尾部具有显著的近端圆锥形和远端纤细的圆柱形,圆柱形部分占尾部的2/3。似三核线虫厦门种（Tripyloides amoyanus n.sp.）口器分成3部分,具有小齿,化感器小,双环状,尾部1/3部分为圆柱形,引带有4个小齿。  相似文献   

5.
本研究利用高通量测序技术获得采自新疆昭苏琥珀螺科一未知种的线粒体全基因组序列。该种琥珀螺线粒体基因组全长14219bp,由13个蛋白质编码基因,22个tRNA基因,2个rRNA基因及1个控制区组成。基因组中AT含量为76.43%,GC含量为23.57%,表现出明显的AT偏好性。13个PCGs多使用ATG为起始密码子,TAA为终止密码子。tRNA基因中tRNA-Ser1和tRNA-Ser2缺少DHU臂,其中tRNA-Ser1在缺失的DHU臂处有一个小的茎环结构。非编码区位于COX3与tRNA-Ile之间,长度为58bp。琥珀螺科中现有腐败琥珀螺Succineaputris、五家渠尖缘螺Oxylomawujiaquensis和Omalonyxunguis的线粒体基因组被报道。三者的基因排列顺序和结构基本相似。昭苏琥珀螺未知种的基因排列顺序与它们有所不同。昭苏琥珀螺未知种的tRNA-Tyr和tRNA-Trp基因位于COX2和tRNA-Gly之间,上述三种tRNA-Tyr和tRNA-Trp基因位于tRNA-Ser2和tRNA-Ser1之间。系统发育树结果显示,琥珀螺科的四种聚为一支,为单系群,其中腐败琥珀螺和Omalonyxunguis亲缘关系更近。本研究结果支持昭苏琥珀螺未知种为中国一未报道的属种,但要确定其是否为一新属新种尚需更多的分子和形态数据。  相似文献   

6.
Seventeen demersal fish species collected during a commercial line fishing trip off northern New Zealand are listed together with data on abundance, location, and habitat. These are the first records for the area; 15 are the most northerly records for the species and major range extensions are recorded for Centroscymnus owstoni, Deania calcea, Etmopterus lucifer, Pseudophycis barbata, and Hyperoglyphe antarctica. A prespawning aggregation of ling, Genypterus blacodes, is recorded for the first time from this region.  相似文献   

7.
贻贝隶属于软体动物门(Mollusca)、双壳纲(Bivalvia)、翼形亚纲(Pteriomorphia)、贻贝目(Mytilida)、贻贝超科(Mytiloidea),大约有400种贻贝分布在世界各地,可适应淡水、潮间带至深海多种生境。本实验以贻贝科6亚科12属28种中国沿海常见贻贝的28SrDNA为目的片段,构建系统发育进化树,运用最大似然法和贝叶斯推演法分析了贻贝科的系统发生,并追踪贻贝科物种系统演化历史。结果显示:贻贝亚科Mytilinae、偏顶蛤亚科Modiolinae、石蛏亚科Lithophaginae均非单系群。在属阶元,深海偏顶蛤属Bathymodiolus、贻贝属Mytilus和股贻贝属Perna为单系群。本研究发现应接受将原隔贻贝属Septifer分为Septifer属和Mytilisepta属的分类提议;应接受将原石蛏属Lithophaga中的膜石蛏亚属Leiosolenus提升至属的地位的分类提议。此外,短齿蛤属Brachidontes的单系性不被支持,刻缘短齿蛤Brachidontessetiger并未与短齿蛤属其他物种在系统发育树上聚拢,亲缘关系较远,为不同属物种,建议恢复刻缘短齿蛤原属名Volsella (Dunker, 1857)。  相似文献   

8.
Several species of Gastrotricha were found among samples of nematodes extracted from a sandy ocean beach, South Broulee beach, in southeastern Australia. One of these Gastrotricha turned out to be a species new to science which is described as Halichaetonotus australis sp. nov. in this study. Although the spines of the hydrofoil scales resemble those of the cosmopolitan H. aculifer, a distinctive feature of the new species is the presence of three prominent posterior dorsal spines. These are exaggerations of the keels found on the dorsal overlapping scales that cover the dorsal surfaces of the head, neck, and trunk. The spines are almost as long as the rami of the terminal furca. H. australis sp. nov. also resembles H. marivagus, but differs in lacking both a cephalion and hypostomion. Freeze drying is introduced as a preparation method for scanning electron microscopy of Gastrotricha.  相似文献   

9.
蛟龙号载人潜水器在位于雅普海沟北部6 745 m深处的底栖沉积环境中采集到两只石鳖样本,这是石鳖物种分布于此的新记录。形态学和DNA分子标记均支持两只石鳖为鳞侧石鳖属（Leptochiton）同一物种。该种在形态上与L.vanbellei和L.deforgesi接近;在系统发生方面,与L.vanbellei,L.deforgesi和L.boucheti的亲缘关系密切。这是截至目前世界石鳖分布报道的第三深度记录。  相似文献   

10.
相手蟹科的诸多种类因其形态极其相似成为方蟹总科分类中疑问较多的一个类群。通过对中国沿海相手蟹线粒体COI和16S rRNA基因序列进行分子系统发育分析,结果表明14种相手蟹COI和16S rRNA基因序列之间差异分别为5.7%～14.5%和1.5%～12.1%,均达到了种间差异水平。构建的系统发育树显示,14种相手蟹分别为独立有效物种,但分属于拟相手蟹属和近相手蟹属的4种拟相手蟹和3种近相手蟹,没有分别形成2个独立的支系,而是混合聚成一大支系。而属于螳臂相手蟹属的无齿螳臂相手蟹则首先与属于中相手蟹属的中华中相手蟹聚成一支,再与红螯螳臂相手蟹聚为一大支,表现出与形态分类的不一致。错综复杂的分子系统关系预示着相手蟹类为多系起源,也表明它们之间的种间关系乃至于属间关系尚有诸多问题有待进一步厘定。  相似文献   

11.
调查了大亚湾海域13种石斑鱼(Epinephelus spp.)寄生单殖吸虫群落,结果发现有10种鱼感染单殖吸虫,占调查鱼种类的四分之三,检获单殖吸虫16种,隶属于3科5属,其中拟合片虫属(Pseudorhabdosynochus spp.)10种;除鞍带石斑(E.lanceolatus)和拟青石斑(E.fasciatomaculosus)外,8种鱼可分别感染3—7种单殖吸虫;感染单殖吸虫种类最多的是玳瑁石斑(E.quoyanus)达7种,次之是青石斑(E.awoara)和养殖的橙点石斑(E.bleekeri)均感染6种;各单殖吸虫种类中,感染强度最大的是拟合片虫(P.serrani))(棕点石斑,E.fuscoguttatus)128只/尾,次之是石斑拟合片虫(P.grouperi)(青石斑)62只/尾,接下来是斜带拟合片虫(P.coioidesis)(大斑石斑,E.macrospilos)59只/尾和杯阴拟合片虫(P.cupatus)(玳瑁石斑)49只/尾;平均密度最高的是棕点石斑上检获的拟合片虫128只/尾;在检获的16种单殖吸虫中,8种可分别寄生于2种或2种以上石斑鱼,石斑鳞盘虫(Diplectanum grouperi)和拟合片虫在6种石斑鱼上都能检获,符合广寄生单殖吸虫种特征。有5种鱼检查尾数5尾以上的,其中玳瑁石斑单殖吸虫感染率最高62.07%,其内群落的物种丰富度与宿主体长呈显著正相关。  相似文献   

12.
Marthasterias glacialis are found in the cool-temperate waters of the north-eastern Atlantic Ocean, in the subtropical waters of the Mediterranean Sea and along the south-western tip of Africa. The South African Marthasterias population includes two morphotypes, a smooth, spineless rarispina form and a spiny africana form, that have been described as separate species, subspecies, or forma by various authors over the past century. To test whether these two morphotypes represent separate species, and whether either, or both, are conspecific with the North-East Atlantic species, 78 Marthasterias were collected from the Cape Peninsula of South Africa. Morphological comparisons between individuals of the two forms showed no significant clustering of samples, indicating that there is no morphological separation of the two South African forms into distinct groupings. The africana and rarispina forms were also shown to be genetically indistinguishable, using a fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene and the nuclear internal transcribed spacer 1 (ITS1). In addition, the COI sequences were also compared to those from European specimens, and phylogenetic reconstruction and intra- and interspecific levels of divergence suggested that the South African specimens form a single group that is genetically distinct from the European M. glacialis. Although the allopatric distribution, high genetic divergence (more than 3% for the COI fragment) and morphological differences suggest that the South African form should be raised to species status under the name Marthasterias africana, further work must assess an independent genetic marker (nuclear) to support raising the COI clade to species level. True M. glacialis have a spine-armament pattern of a series of three or more regular spine rows down the length of each arm, whereas M. africana are either covered in many irregularly spaced spines, or have an extraordinarily bare surface with only two spine rows per arm. Marthasterias africana may also have an actinal spine simulating the presence of a third inferomarginal spine. This work tentatively resolves the taxonomic dispute, elucidates the separation and amalgamation of the two African forms and suggests a single, uniquely South African Marthasterias species that might be distinct from the north Atlantic M. glacialis, although further analyses to test reproductive isolation between the North-East Atlantic and South African forms are required.  相似文献   

13.
A new homoscleromorph sponge species was observed for the first time in 2002 along the coast of Provence (France) and since then, several investigations have been implemented. The new homoscleromorph species is devoid of skeleton and it is thus related to the Oscarella genus. Oscarella balibaloi sp. nov. has been found in several littoral submarine caves of the Western Mediterranean Sea (France and Spain). After several years of monitoring, we show that this sponge is becoming abundant in several locations. The species has a peculiar habit, often overgrowing massive sponges, gorgonians or some erected bryozoans. Oscarella balibaloi sp. nov. is thinly encrusting, with an irregular morphology, lobate surface, and soft and very slimy consistency. Its color is white to orange. At the cytological level, this new species is characterized by three distinct types of cells with inclusions in its mesohyl: one with vacuoles and the others with paracrystalline inclusions. The reproduction pattern is very similar to other Oscarella species. We also present a specific metabolic fingerprint and compare it to that of other Mediterranean Oscarella species.  相似文献   

14.
为了明确分布于中国海域点带石斑鱼(Epinephelus malabaricus)、青石斑鱼(E.awoara)、巨石斑鱼(E.tauvina)、六带石斑鱼(E.sexfasciatus)和宝石石斑鱼(E.areolatus))等石斑鱼属(Epinephelus)鱼类的系统发育关系,作者采用PCR和DNA测序技术,测定了5种石斑鱼属鱼类的核糖体DNA ITS1序列,获得其ITS片段长度分别为537、536、535、528、532 bp。研究结果表明:5种石斑鱼r DNA ITS1序列的碱基组成趋势相似,A+T含量皆低于C+G含量,A+T含量最低为宝石石斑鱼(37.6%),最高为六带石斑鱼(41.5%);基于Kimura-2双参数模型计算得到上述石斑鱼种间遗传距离在0.0000~0.3002。基于MP法、ML法和NJ法构建的3种分子系统树表明,r DNA ITS1序列与形态呈同步进化关系,宝石石斑鱼与其他4种石斑鱼的亲缘关系较远,表明在所研究的物种中最早分化而出,而点带石斑鱼与青石斑鱼的亲缘关系最近,分化的时间最晚。  相似文献   

15.
The whale‐louse Scutocyamus antipodensis n.sp., ectoparasitic on Hector's dolphin, Cephalorhynchus hectori (van Beneden), is described and figured from material collected in Cloudy Bay, Cook Strait, New Zealand. Morphologically the new species is very close to S. parvus Lincoln & Hurley, the type and only other species of the genus, known only from the North Sea. However, the two species differ in the detailed structure and spinosity of the body and pereopods.  相似文献   

16.
This study investigated differences in Symbiodinium diversity in the scleractinian coral species Agaricia lamarcki between shallow (20–25 m) and mesophotic (50–70 m) depths in the Northern Caribbean. Corals were sampled in each of four shallow sites (20–25 m; n = 18) and three mesophotic sites (50–70 m; n = 18) from Mona Island (Puerto Rico) and the US Virgin Islands during a mesophotic exploratory cruise and from the La Parguera shelf edge, off Southwestern Puerto Rico. Symbiodinium diversity was assessed using internal transcribed spacer 2 sequences clustered into operational taxonomic units (OTUs). Clustering resulted in eight clade C OTUs and one clade D OTU. Of these, there were three common Symbiodinium OTUs consisting of C3 and D1a.N14 in shallow reefs and C11.N4 in mesophotic reefs. Statistical tests (permutational multivariate analysis of variance and analysis of similarity) showed significant differences between clade C Symbiodinium OTUs in A. lamarcki colonies located at shallow and mesophotic depths, indicating symbiont zonation. Symbiodinium diversity in A. lamarcki from the Northern Caribbean is comparable to previous reports in the Southern Caribbean for this species. This is the first report of the thermal tolerant species Symbiodinium trenchii (D1a) in A. lamarcki.  相似文献   

17.
通过整理近年来中国科学院海洋研究所采集的深海海参标本,发现了"蛟龙"号载人潜水器在南海珍贝海山水深2463m处采集的1号蝶参科标本,经鉴定为一个新记录属底游参属Benthodytes Théel, 1882的一个新记录种西伯加底游参Benthodytes sibogae Sluiter, 1901。西伯加底游参与底游参属其他物种的显著差异在于其背部有5—6对大疣,沿背部步带区近乎对称的排列为两行。本文对新记录种的外部形态特征进行了详细的描述,与该种的模式标本进行了分类学讨论,提出背部大疣的数量及排列方式为该属物种区分的重要依据。在对骨片进行超微结构研究时发现,该种背部疣足的骨片与背部和腹部体壁骨片在大小、中央突起的高度和分叉部位上有较大差异,此前的报道未对疣足骨片进行过描述,本文对此进行了补充。  相似文献   

18.
Four similar sponges of different colors, all unknown to science, were collected in submarine caves of New Caledonia. We aimed at determining whether the four chromotypes represented different species or phenotypic variations of a unique new species. We used an integrative taxonomic approach combining morphologic, molecular and metabolomic analyses. The main traits that define these specimens are a skeleton made of monolophose, trilophose and tetralophose calthrops only, high chemical diversity and a high abundance and diversity of prokaryotic symbionts. The symbiotic community includes two unique prokaryote morphotypes, which are described for the first time in Homoscleromorpha, and appeared to be vertically transmitted. Although several features slightly differ among chromotypes, the most parsimonious conclusion was to propose a single new species Plakina kanaky sp. nov. Our phylogenetic analysis indicated the paraphyly of the Plakina genus, with P. kanaky sp. nov. belonging to a clade that includes Plakina jani and Plakina trilopha. The present work demonstrates that integrative taxonomy should be used in order to revise the entire Plakinidae family and especially the non‐monophyletic genus Plakina.  相似文献   

19.
拟相手蟹属因其形态极其相似成为相手蟹科分类中最有疑问的一个属。通过对中国沿海近亲拟相手蟹Parasesarma affine、斑点拟相手蟹P. pictum、三栉拟相手蟹P. tripectinis、P. ungulatum及褶痕拟相手蟹P. plicatum 5种拟相手蟹的形态对比发现,可从它们的螯足形状(包括螯足掌节背面的梳状栉,可动指背面突起数目)及雄性第一腹肢形状对其进行区分。对其线粒体16S rRNA基因序列进行分子系统发育分析,结果表明5种拟相手蟹之间的遗传距离为1.9%～9.3%,达到了种间差异水平;构建的系统发育树显示近亲拟相手蟹与褶痕拟相手蟹汇聚成一支,随后与P. ungulatum聚在一起,斑点拟相手蟹与三栉拟相手蟹汇聚成独立支系。形态和分子证据均支持5种拟相手蟹分别为独立有效物种。  相似文献   

20.
In a study of meiofauna polychaete from the Huanghai Sea, a previously undescribed species belonging to Hesionura has been found and described. The new species differs from the other species of the genus Hesinura mainly by the chaetation.  相似文献   

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