Increasing imposex in populations of Bolinus brandaris (Gastropoda: Muricidae) in the northwestern Mediterranean.

The muricid gastropod Bolinus brandaris exhibited imposex, a phenomenon linked to the use of organotin biocides. Several stages of imposex development (1-5) could be distinguished and were documented with SEM-photographs for the first time in this species. Additional alterations of the genital tract in females (blocked vulva preventing copulation and deposition of egg capsules) and males (excrecences on the penis and vas deferens) were shown. Imposex intensity on the Catalan coast was very high. The frequency of imposex off Barcelona and Vilanova i la Geltrú was 100%, with all females showing stage 4. Imposex frequency off Sant Carles de la Ràpita was 99.7% and the VDS index scored 3.9. Despite regulations of TBT-containing antifouling paints in Spain since 1990, the present study revealed that frequency and intensity of imposex have increased on the Catalan coast, at least since 1997. However, at present, imposex does not apparently affect the population dynamics of B. brandaris in the studied area, since no serious consequences on female reproduction (only one case of female sterilization) were detected. Gonadal activity and oogenesis were not suppressed or supplanted by spermatogenesis. Sex ratios were not male-biased. Possible sources of organotin biocides are examined.     

Nursery areas of red mullet (Mullus barbatus), hake (Merluccius merluccius) and deep-water rose shrimp (Parapenaeus longirostris) in the Eastern-Central Mediterranean Sea

The spatial pattern of the nursery areas of red mullet (Mullus barbatus), hake (Merluccius merluccius) (Linnaeus, 1758) and deep-water rose shrimp (Parapenaeus longirostris) (Lucas, 1846) was studied in the South Adriatic and North Ionian Seas (Eastern-Central Mediterranean) applying geostatistical techniques and data from time series trawl surveys conducted in the area. The analysed variables were: R (number of recruits/km²) and R/Tot (fraction of recruits on the total sampled population). The structural analysis showed a spatial pattern of both variables characterized by continuity on a small scale. Predictions of nursery area localization with probability of finding recruits at different threshold values were obtained through median indicator kriging. For the red mullet the nurseries were mainly identified in the South Adriatic Sea off the Gargano peninsula and between Molfetta and Monopoli within 50 m in depth. The main concentration of hake juveniles was found to be between 100 and 200 m in depth along the Gargano peninsula and between Otranto and Santa Maria di Leuca, where a nursery of deep-water rose shrimp was also detected. An overlapping depth, between 100 and 200 m, was identified for hake and deep-water rose shrimp nurseries. Protection of these areas through limitations of fishing pressure is discussed.     

沼蜷属螺一新种记述(腹足纲: 黑贝科)

探讨并殖吸虫螺类宿主自然资源。发现采自福建北部的沼蜷属螺Paludomus一新种,命名为闽北沼蜷。参照《医学贝类学》和相关文献进行形态描述。正模(FJ6135)壳高18.15 mm,壳宽13.46 mm,壳口高14.05 mm,壳口宽8.04 mm。产地武夷山九曲溪。螺层5层,顶层及原壳层多缺失,螺面呈绿褐色,各螺层宽度上向体螺层增长迅速,体螺层大而膨胀,其高度上约占全部高度的4/5。齿舌中央齿呈尖峰状,中部支齿大而突出。内缘齿单支而宽大,两侧缘各有3或5枚不甚突出小齿,分布不对称,排列公式:3-1-3,3-1-5(3),7,5。本新种可与黔沼蜷(P.quianensis Liu et al,1994)、带沼蜷(P.cinctus Liu et al,1994)比较鉴别。     

Small-scale distribution characteristics of Munida spp. populations (Decapoda: Anomura) off the Catalan coasts (western Mediterranean)

The small-scale distribution characteristics of three species of the anomuran genus Munida, namely Munida rutllanti, Munida intermedia and Munida tenuimana, have been studied on the lower shelf and upper-middle continental slope near the coasts of Tarragona and the Ebro delta region in the western Mediterranean. The differential bathymetric distribution showed that a fair degree of overlap exists between M. rutllanti and M. intermedia, with the former being mainly found at shallower depths. The size population structure of the three species showed that polymodality, as indicative of a longer life-span and of a higher degree of population structuring was more evident in the deeper-living species, whereas unimodality, as an indication of a recruitment dependent population, was more evident in the shallowest-occurring species. Geostatistics have been applied to determine the degree of spatial variability occurring in M. intermedia abundance, the better-sampled species. The Mantel test has been used to assess the significance of the overlap between the three species distributions as well as the relation between certain population parameters. A discussion on the population characteristics of M. rutllanti is made in relation with its expansion along the western Mediterranean in the last decades.     

Comparison of the biology, dynamics, and secondary production of Talorchestia brito (Amphipoda, Talitridae) in Atlantic (Portugal) and Mediterranean (Tunisia) populations

The biology, population dynamics, and production of Talorchestia brito were studied at two sandy beaches located on the Atlantic (Portugal) and on the Mediterranean (Tunisia) coasts, respectively. The seasonal variation in abundance and the overall densities were similar in both populations. Reproduction occurred from February to September in the Atlantic, and from March to early November in the Mediterranean. The sex ratio was male biased in the Atlantic, and female biased in the Mediterranean. Based on data from the Atlantic population, both abundance and the proportion of reproductive females were positively correlated with temperature, while the proportion of juveniles in the population was positively correlated with temperature and sediment moisture. On average, individuals from the Atlantic were larger than the ones from the Mediterranean. Life span was estimated at six to nine months in the Atlantic, and five to eight months in the Mediterranean. Talorchestia brito was shown to be a semiannual species, with iteroparous females producing two broods per year, and exhibited a bivoltine life cycle. The minimum age required for males' and females' sexual differentiation and for female sexual maturation was shorter in the Mediterranean. Growth production (P) was estimated at 0.19 g m⁻² y⁻¹ ash free dry weight (AFDW; 4.3 kJ m⁻² y⁻¹) in the Atlantic population, and 0.217 g m⁻² y⁻¹ AFDW (4.9 kJ m⁻² y⁻¹) in the Mediterranean one. Elimination production (E) was estimated at 0.35 g m⁻² y⁻¹ AFDW (7.9 kJ m⁻² y⁻¹) in the Atlantic, and 0.28 g m⁻² y⁻¹ AFDW (6.3 kJ m⁻² y⁻¹) in the Mediterranean. The average annual biomass ( ) (standing stock) was estimated at 0.032 g m⁻² in the Atlantic beach, and 0.029 g m⁻² in the Mediterranean one, resulting, respectively, in ratios of 5.9 and 7.5 and ratios of 10.8 and 9.6. Like other talitrids, T. brito exhibited geographic variation in morphometrical characteristics, sex ratio, growth rates, life span, and reproduction period, with the Atlantic population presenting a slower life history.     

中国近海鱼篮螺属的分类以及种名修订(腹足纲, 蛾螺科)

对分布于中国近海的蛾螺科Buccinidae、鱼篮螺属Nassaria种类进行了系统的分类学研究,确定了其分类地位,共鉴定出该属12种,分别为:尖鱼篮螺Nassaria acuminata(Reeve,1844),尖旋鱼篮螺N.acutispirata(Sowerby,1913),多刺鱼篮螺N.cirsiumoides Fraussen,2004,带扣鱼篮螺N.fibulaFraussenStahlschmidt,2008,光滑鱼篮螺N.laevior Smith,1899,美好鱼篮螺N.magnifica(Lischke,1871),坚硬鱼篮螺N.solida(KurodaHabe in Habe,1961),棘刺鱼篮螺N.spinigera(HayashiHabe,1965),缝合鱼篮螺N.suturalis(Adams,1855),脉管鱼篮螺Nassaria varicosa ZhangZhang,2014以及两个鱼篮螺未定种Nassaria sp.。文中对物种的主要鉴别特征进行了描述,并根据最新分类系统对相关种名进行了修订。     

Temporal and spatial variability in shallow- and deep-water populations of the invasive Caulerpa racemosa var. cylindracea in the Western Mediterranean

The invasive green alga Caulerpa racemosa var. cylindracea represents an important threat to the diversity of Mediterranean benthic coastal ecosystems by interfering with native species and modifying benthic assemblages. The present study deals, for the first time, with the temporal and spatial variability of the biomass and phenology of C. racemosa considering both deep- and shallow-water populations. Two sampling depths (30 and 10 m) were sampled at three different rocky bottom sites every 3 months in the Archipelago of Cabrera National Park (Western Mediterranean). All morphometric variables analysed showed a spatial variation and temporal patterns depending on depth. Between depths, C. racemosa biomass, stolon length, number of fronds and frond length were usually significantly higher at deep-water populations, suggesting that C. racemosa grows better in deep-waters. Deep- and shallow-water populations displayed a high temporal variation although no evidence of seasonal patterns was found, in contrast with what has been reported by other authors. The sources of this variability are still unknown but probably both physical factors and differential herbivory pressures display a key role.     

Shallow Cystoseira (Fucales: Ochrophyta) assemblages thriving in sheltered areas from Menorca (NW Mediterranean): Relationships with environmental factors and anthropogenic pressures

The distribution of Cystoseira species was studied at 103 coves in the island of Menorca (Balearic Islands, NW Mediterranean). Both geomorphological parameters and anthropogenic pressures were considered in order to investigate which were the main environmental factors explaining their distribution. Several factors contributed to explain the composition of Cystoseira assemblages in the sampled coves being coastal morphology, bottom nature, nutrient concentration in seawater and urbanization level of the coast the most important. The relatively high number of Cystoseira species found in Menorca suggested a general high quality of the environment. However, in southern coves the number and abundance of Cystoseira spp. was reduced compared to the northern ones. This pattern seems to be related both to a higher anthropogenic pressure and to a less favourable geomorphology at southern coves. When strong anthropogenic disturbances were present (proximity to harbour areas), coves were completely devoid of Cystoseira specimens. As historical data is available for some of these sites, we can document the disappearance of some Cystoseira species at these coves, which seems to be related to increased pollution levels. However, as the absence of Cystoseira assemblages can also respond to a lack of a suitable geomorphology, their use as bioindicators of water quality needs of a definition of proper reference sites.     

High occurrence of the elasipodid holothurian Penilpidia ludwigi (von Marenzeller, 1893) in bathyal sediment traps moored in a western Mediterranean submarine canyon

One hundred and fifty specimens of the elasipod holothurian Penilpidia ludwigi (von Marenzeller, 1893) were collected in sediment traps moored near the seabed in the La Fonera Canyon (Catalan Sea, north-western Mediterranean) and on the adjacent continental slope. These provide the third record of this apparently endemic Mediterranean species and the first record from the western Mediterranean. This was the only holothurian species trapped and the most abundant macroscopic organism found in the traps between 1200 and 1700 m depth over the whole sampling period (March–November 2001). It was particularly abundant in spring during the main flux of organic particles in the canyon. This coupling suggests that Penilpidia may aggregate at the seafloor during these events, making food availability a plausible explanation of the seasonal occurrence. Lateral transport of material re-suspended locally or up-canyon by near bottom currents appear to be the mechanism behind this uncommon occurrence, although in situ observations have recently been made on the swimming capability of this holothurian. The occurrence of benthic organisms in sediment traps set close to the seabed can provide information on bathyal benthic and benthopelagic populations.     

Appearance of Chelophyes appendiculata and Abylopsis tetragona (Cnidaria, Siphonophora) in the Bay of Villefranche, northwestern Mediterranean

The vertical and temporal distribution of two calycophoran siphonophores, Chelophyes appendiculata (Eschscholtz, 1829) and Abylopsis tetragona (Otto, 1823) in the Bay of Villefranche (northwestern Mediterranean) was investigated by an analysis of three different planktonic time series. A daily series (1993–1995) showed seasonal peaks of the nectophores of C. appendiculata during spring and particularly in late summer, while the abundance of A. tetragona remained similar throughout the year. A weekly series (1994–1995) showed that C. appendiculata (nectophores and eudoxids) became concentrated above the thermal discontinuity, in the most stratified and warm waters, whereas A. tetragona was collected in large numbers below this discontinuity. A 27-year survey (1966–1993) showed long-term fluctuations of these siphonophore populations, which became abundant in the Bay starting from 1980 and especially after 1984, when the water column grew warm and hypersaline, corresponding to a less rainy period. Temporal (seasonal and long-term) and bathymetric (between 10 and 60 m depth) successions of these two siphonophores were noted in this shallow coastal bay.     

Feeding ecology of Ammothella longipes (Arthropoda: Pycnogonida) in the Mediterranean Sea: A fatty acid biomarker approach

Fatty acid analysis has proved valuable in determining seasonal trophic links and the feeding behavior in organisms in which these diet and trophic links cannot be inferred from stomach content analyses. Seasonal variations in total free fatty acid content (TFFA) and fatty acid composition of seston (<250 μm), the brown macroalgae Stypocaulon spp., polychaetes (Nereididae) and the pycnogonid Ammothella longipes have been used to establish their trophic links, with particular focus on seasonality and feeding ecology of A. longipes. Samples were collected in a coastal environment (NW Mediterranean Sea) at 7–10 m depth, in five different periods (August and October 2008, February, June and September 2009). Seston and Stypocaulon spp. samples did not show significant seasonal variations in TFFA content, while nereids showed a significant variation. Analysis of fatty acid profile showed high similarities of fatty acid composition between seston and Stypocaulon spp. Nereids were closer to seston and Stypocaulon spp. than A. longipes, which seemed to follow a seasonal trend. The results of this study reveal that A. longipes may change its feeding behavior depending on the season and available food. This pycnogonid species appears to be carnivore during spring and early summer but seems to feed on detritus when availability of prey diminishes during winter. Notable high amounts of odd-chain fatty acids are found in summer–autumn for this species, which may come from bacteria acquired from the detrital diet or from de novo biosynthesis from propionate. The results obtained provide new and valuable data on the understudied feeding biology of pycnogonids in general, and contribute to the understanding of their functioning of Mediterranean shallow oligotrophic systems and their trophic links.     

Morphometric or morpho-anatomal and genetic investigations highlight allopatric speciation in Western Mediterranean lagoons within the Atherina lagunae species (Teleostei, Atherinidae)

Current distribution of Atherina lagunae poses an interesting biogeographical problem as this species inhabits widely separate circum-Mediterranean lagoons. Statistical analyses of 87 biometric parameters and genetic variation in a portion of the cytochrome b gene were examined in four populations of A. lagunae from Tunisian and French lagoons. The results suggested a subdivision into two distinct Atherinid groups: one included the French lagoonal sand smelts and the second included the Tunisian ones. Tunisian lagoonal sand smelts were distinguished from the French ones by the lower number of lateral line scales, vertebrae, pectorals and first dorsal fin rays and the higher number of lower and total gillrakers. In addition, A. lagunae from Tunisian lagoons are characterised by short preorbital length, developed operculum, broad interorbital space, larger head, robust body and a relatively small first dorsal fin which is positioned backwards. In addition, intraspecific sequence variation in a portion of the cytochrome b gene was examined in 87 individuals from Tunisia and France. The high correlation between the results of the molecular phylogenetic tree and biometric statistical data analysis suggested that two different sibling species or at least sub-species or semi-species have colonised the lagoons. In addition, our analyses suggested that the evolution of A. lagunae probably occurred in two steps including marine sympatric speciation within the large Atherina boyeri complex and a post-Pleistocene colonisation of the lagoons.     

糖原含量与糖原磷酸化酶基因(GPH)和己糖激酶基因(HK)的表达在福建牡蛎生殖周期中的相关性分析

Glycogen, a polymer of glucose, is an important means of storing energy. It is degraded by glycogen phosphorylase (GPH) and hexokinase (HK), glycogen phosphorylase, and hexokinase cDNAs (Ca-GPH andCa-H...     

中国海域长眼寄居蟹属两个新记录种

在我国南海海域大型底栖生物进行分类和多样性研究中,发现我国长眼寄居蟹属2个新记录种,紫斑长眼寄居蟹(Paguristes gonagrus)和条纹长眼寄居蟹(Paguristes runyanae),并对其进行描述。紫斑长眼寄居蟹采集自海南岛,主要特征为：螯足和步足密布刚毛,第一触角柄未达到角膜基部,螯足腕节、掌节背面刺和突起密集而发达,螯足和第二、三步足长节末端有紫色色斑;条纹长眼寄居蟹采集于西沙群岛,主要特征为：右螯足略大于左螯足,第一触角柄短,长度仅为眼柄长度的1/2,螯足和第二、三步足背腹面均有黄色条纹。     

中国尖缘螺属一新种记述(柄眼目, 琥珀螺科)

作者利用形态解剖和扫描电镜方法对采自新疆五家渠市琥珀螺科(Succineidae)一未知种类进行了研究。结果如下:该种贝壳长卵圆形,黄棕色,壳质薄,半透明,中等大小,壳高12.56~15.10 mm,壳宽6.48~7.72 mm,有2.8~3.1个螺层;软体密布色素点,整体黑褐色;阴茎较短,绝大多数个体阴茎一侧扩展呈片状沿纵向与囊状的另一侧相折叠;阴茎附属物片状,长度约为阴茎长度的1/4;阴茎基背板长,在阴茎鞘中折叠6~7次;阴茎内部具数条纵褶,阴茎内表面密布微小乳状突。结果显示该种属于尖缘螺属(Oxyloma),与该属已报道的相近种差异明显,为一新种,即五家渠尖缘螺(Oxyloma wujiaquensis sp.nov.)。模式标本保存于新疆大学生命科学与技术学院。     

中华蛸寄生丛集球虫(顶复亚门:丛集球虫科)新种的形态学与分子生物学研究

丛集球虫(顶复亚门:类锥体纲:丛集球虫科)是头足类消化道中一类常见寄生虫,在福建连江海域以及浙江南麂岛周边海域采捕到的中华蛸(Octopussinensis)盲囊及肠组织内发现一丛集球虫新种,命名为多刺丛集球虫Aggregata octaculeata sp. nov.。光学显微镜和扫描电镜下观察发现,中华蛸体内的多刺丛集球虫存在配子生殖阶段和孢子生殖阶段,其中,孢子生殖阶段成熟卵囊呈近球形或椭球形,长径653.6—806.5μm,短径588.1—787.1μm。孢子囊为卵球形或椭球形,长径22.4—26.1μm,短径20.5—24.6μm,孢子囊壁为双层,外部光滑,内层多刺。孢子囊内子孢子呈卷曲状,数目范围8—13个,子孢子长度为22.2—28.6μm,宽度为3.0—5.0μm。基于18SrRNA基因构建的系统发育树进一步证实该物种隶属于丛集球虫属,并高度支持了属内[(中华丛集球虫A. sinensis+A. octopiana)+A. eberthi]+多刺丛集球虫A. octaculeata的系统发生关系。     

副溶血弧菌攻毒过程中文蛤肝胰腺弧菌载量变化的分析

文蛤(Meretrixpetechialis)是我国一种重要的海水养殖贝类,其养殖过程中病害导致的规模性死亡时有发生,已有的工作证实致病性弧菌是导致文蛤大规模死亡最为常见的病原。在本研究中,我们通过浸泡感染实验模拟了文蛤在自然条件下的弧菌胁迫环境,明确了攻毒水体中弧菌生长变化规律;攻毒过程中宿主载菌量分析显示,文蛤肝胰腺组织弧菌载量在攻毒后呈第1天急剧上升,第3天迅速下降的变化趋势,而且不同个体间载菌量差异较大;通过不同弧菌含量攻毒实验,发现在攻毒早期文蛤体内弧菌载量与水体环境的弧菌含量之间呈显著的正相关(Spearman’sρ=0.899,P=0.000),而在感染中后期不同攻毒强度组之间无显著差异,且呈现较低水平,为0～205CFU/mg,预示着宿主免疫系统和肝胰腺微生物群落可将致病菌的数量控制在一定的范围。上述研究为开展文蛤感染发病过程中弧菌载量和免疫抗性评价相关研究提供了参考。     

基于COI和ITS-1基因对魁蚶野生群体和人工繁育子代的遗传分析

采用线粒体 COI 基因和核糖体第一内转录间隔区 ITS-1基因,对荣成(RC)和即墨(JM)2个魁蚶(Scapharca broughtonii Schrenck)野生地理群体及一个人工繁育的即墨子代(JZ)群体,进行遗传多样性和遗传结构分析,探讨即墨人工繁育的子代作为荣成魁蚶底播增殖苗种的可行性。分子方差分析(AMOVA)结果表明,3个群体的遗传差异主要存在群体内。荣成野生群体和即墨野生群体间的Fst值,基于COI基因和ITS-1基因分别为0.1678和0.1193,表明荣成野生群体与即墨野生群体之间存在中等程度的遗传分化。单倍型多样性和核苷酸多样性分析结果表明,人工繁育的即墨子代群体的遗传多样性明显降低。荣成野生群体与即墨子代群体之间的遗传差异,较之与即墨野生群体间的遗传差异更大。如果采用即墨子代在荣成底播,可能会对荣成野生魁蚶野生群体的遗传结构产生一定影响,因此,采用即墨人工繁育子代作为荣成魁蚶底播增殖的苗种来源时必须十分慎重,并在苗种繁育时尽量采用大群体有效亲本。     

Imposex and surface sediment speciation: a combined approach to evaluate organotin contamination in Guanabara Bay, Rio de Janeiro, Brazil

An integrated biological-chemical survey of organotin compounds was carried out in Guanabara Bay, the second most important Brazilian harbor complex. The biological survey revealed high levels of imposex in Stramonita haemastoma populations. Inside the bay values of relative penis length index from 42.7 to 107.6 and vas deferens sequence index from III to VI were found, while organisms collected outside the bay had values ranging from <0.1 to 35.2 and from 0 to II. None of the females sampled inside the bay were normal and imposex was found in all stations. Surface sediments in the bay are contaminated by tributyltin (10-522 ng/g d.w.) and triphenyltin (<3.9-39.4 ng/g d.w.) with greater concentrations close to shipyards and marinas. The observed predominance of parent compounds (TBT and TPT) is commonly found when recent inputs occur, but may also indicate slow degradation processes in the anoxic conditions of these sediments. To our knowledge, this is the first report of a combined imposex-sediment approach to evaluate organotin contamination in marine environments of South America, and also the first report of TPT detection in environmental matrices in this region.     

斑节对虾TSG101基因的克隆及表达分析

为探究肿瘤易感基因101(简称TSG101)对斑节对虾(Penaeusmonodon)的免疫应答作用,了解在细菌刺激下斑节对虾的机体发生的变化机制,本研究以哈维弧菌(Vibrioharveyi)和金黄色葡萄球菌(Staphylococcusaureus)为实验组,以磷酸缓冲液(PBS)为对照组,通过荧光定量分析展开对斑节对虾对菌刺激的免疫应答作用。结果显示,斑节对虾的TSG101在各组织中均有表达,在肝胰腺中的表达量最高。在金黄色葡萄球菌刺激下,斑节对虾的TSG101在肝胰腺中的表达量与对照组相比呈极显著上调(P0.01),第12小时的TSG101 mRNA的表达量达到最大(为对照组的21.60倍);在鳃中的表达量与对照组相比呈极显著上调(P0.01),第6小时斑节对虾TSG101的表达量达到最大值(为对照组的3.64倍)。在注射哈维弧菌第9小时,肝胰腺中的PmTSG101 mRNA表达量极显著上调(P0.01)且达到最大(为对照组的2.50倍)。实验结果初步表明,斑节TSG101参与斑节对虾的先天免疫反应,在金黄色葡萄球菌和哈维弧菌的刺激的情况下,该基因RNA水平的表达情况发生明显变化。