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1.
Abstract. The caprellid (Crustacea: Amphipoda) community associated with the alga Cystoseira usneoides (L.) Roberts 1967 was studied on a spatial scale in relation to the influence of environmental factors on the coast of Ceuta (North Africa) using multivariate analyses. Twenty-two stations were sampled and five environmental factors were tested (hydrodynamics, silting, suspended organic matter, organic matter in silt and suspended solids). The spatial distribution of the caprellid community reflected the physico-chemical conditions of the coast. Phtisica marina Slabber 1769 was the only species present at the stations of the harbour of Ceuta, characterised by the lowest values of hydrodynamics and the highest values of silting, suspended organic matter and suspended solids. The most exposed stations (high hydrodynamics and low values of silting, dissolved organic matter and suspension solids) were mainly dominated by Caprella danilevskii Czerniavskii 1868 and C. penantis Leach 1814. These two species have developed a "parallel" posture that enables them to attach strongly to the substratum and thus inhabit areas subjected to heavy exposure or strong currents. Caprella acanthifera Leach 1814 and Pseudoprotella phasma (Montagu 1804) preferred stations characterised by moderate values of silting and suspended solids, such as those located in the coastal areas in front of the city of Ceuta, but these species were not found at the most stressed harbour stations.  相似文献   

2.
The New Zealand Caprellidae (Crustacea: Amphipoda) are reviewed. Only two species previously recognised from New Zealand, Caprella equilibra Say and Caprellina longicollis (Nicolet) are accepted. A new monospecific genus near to Protomima is described.  相似文献   

3.
Orchestia gammarellus (Pallas) will tolerate temperatures from 0°C to c. 30°C but dies in < 1 h at 35°C. Both small and large animals survive > 96 h in water (aerated) between 1 and 60%(.) salinity. In distilled water and 100%(.) brine death occurred after 8–24 h. In fully saline water, pH reduction to c. 3·3 is tolerated. Highly alkaline (pH 11–13) conditions in low salinity media are rapidly fatal. Ammonium concentrations (in fully saline water) some five orders of magnitude higher than normal for seawater are tolerated, reflecting the enhanced ammonium concentration encountered in rotting weed beds. Cl ion concentration equivalent to that in normal seawater will not support O. gammarellus in the absence of Na+ ions. High NO3 concentrations (> 100 mg NO3 litre−1) are fatal in < 24 h. A large range of NaCl concentrations is tolerated (one to two orders of magnitude dilution) by immersed animals. Animals will live longer in air, however, when fed low Na+ food than when immersed in seawater diluted to an equivalent ion strength. Ca2+ and K+ ions cannot substitute for Na+. Orchestia gammarellus will, however, tolerate wide variations in the ratio of Na+:K+ ions (i.e to a shift from 30:1 to 0·3.1) in hypo-osmotic media. At 10°C it will survive c. 5 h of anoxia. It will penetrate into strongly reducing conditions (− 318 mV) even with access to better oxygenated conditions. In nature, behavioural avoidance probably ensures that O. gammarellus does not encounter many of these parameters at acutely limiting values. That this species is so tolerant, however, bears on the evolutionary adaptability of talitrid amphipods to non-marine conditions. Desiccation sensitivity and Na+ ion dependency are the species' most important barriers to life on land.  相似文献   

4.
The concentrations of butyltins along the Japanese coastline were investigated from 1997 to 1999, 7 to 9 years after implementation of legislation limiting the use of tributyltin (TBT) in Japan. Seawater was sampled at 0.5 m depth, and Caprella spp. were collected from Sargassum spp. and aquaculture facilities from 18 areas within four broad areas along the coastline of Japan, i.e., the Pacific coast of northern Japan, the coast along the Sea of Japan, Tokyo Bay and adjacent areas, and western Japan. Butyltins (MBT, DBT and TBT) were detected in 32 of the 63 seawater samples with average concentrations of 4.6 ng MBT/l, 4.5 ng DBT/l and 6.8 ng TBT/l, respectively. Butyltin concentrations in seawater from western Japan indicate "hot spots" even in unpopulated areas. Butyltins (MBT, DBT and TBT) were detected in all samples of Caprella spp., varying from 2.3 ng BTs /g wet wt in C. penantis R-type from Tobishima Island in the Sea of Japan to 464 ng BTs /g wet wt in C. decipiens Mayer from Amakusa, western Kyushu. The BT concentrations in Caprella spp. form western Japan were significantly higher than those from other areas, including Tokyo Bay and adjacent areas, where large scale industry and international ports are located. These results indicate that butyltin contamination still remains even in unpopulated areas after the regulation on TBT usage, and that the regulation governing TBT usage since 1990 has not been effective enough to concede recovery of shallow water ecosystems around Japan.  相似文献   

5.
A preliminary diagnosis is given for Parawaldeckia stephenseni from New Zealand, and the genus is briefly reviewed.  相似文献   

6.
Basic biological investigations on the intertidal amphipod Parhyale basrensis are made. The incubation period is 1–2 weeks. The generation time is 5–6 weeks. Females produce at least 4 broods before they die. The number of eggs carried by the female is a linear function of size of the female. Egg numbers varies from 4–37. Maturity occurs at a size of 4 mm for the female and 4·5 mm for the male. The breeding season is extending from late February to late November or December. Recruitment starts at the beginning of May. Successive broods may have different life spans. The maximum life span of the population is 13–15 months and the minimum life span is 6–7 months.  相似文献   

7.
Benthic amphipod,Grandidierella japonica widely inhabits the Korean coastal waters and is developed as a standard test species for sediment toxicity tests. We exposedG . japonica to various pollutants including 4 kinds of inorganic metals (Ag, Cd, Cu and Hg), tributyltin [TBT], ammonia and 7 polycyclic aromatic hydrocarbon (PAH) compounds (acenaphthene, chrysene, fluoranthene, fluorene, naphthalene, phenanthrene and pyrene) to estimate the no observed effect concentration (NOEC) and the median lethal concentration (LC50) of each pollutant during the 96-hour acute exposure. Among all tested pollutants, TBT was most toxic toG. japonica, and Hg was most toxic among inorganic metals. The toxicity of pyrene toG. japonica was greatest among PAH compounds, followed by fluoranthene, phenanathrene, acenaphthene, fluorene and naphthalene. The toxicity of PAH compounds was closely related to their physico-chemical characteristics such as Kow and water solubility.G. japonica responded adequately to pollutant concentrations and exposure durations, and the sensitivity ofG. japonica to various inorganic and organic pollutants was generally comparable to other amphipods used as standard test species in ecotoxicological studies, indicating this species can be applied in the assessment of environments polluted by various harmful substances.  相似文献   

8.
Abstract

The influence of temperature on the acute toxicity of a technical formulation (86%) and pure formulation (99%) of pentachlorophenol (PCP) to less than 24‐h‐old Simocephalus vetulus neonates was determined with 48‐h static toxicity tests. The technical grade PCP was significantly more toxic to S. vetulus than the pure PCP (P < 0.05). Sensitivity of S. vetulus to technical PCP also significantly increased with temperature (P < 0.05), but a significant temperature effect was not found with the pure PCP. The mean 48‐h LC50 values for neonates exposed to technical PCP were 140 and 199 μg l?1 at 22°C and 16°C, respectively, and for those exposed to pure PCP were 262 and 304 μg l?1, respectively.  相似文献   

9.
1971-1973年,作者在山东省胶南县参加对虾(Penaeus orientalis Kishinouye)人工养殖,发现有几种无脊椎动物是对虾的优良基础饵料,其中特别使我们感到有兴趣的是一种底栖端足甲壳类,它们不仅数量较大,而且繁殖周期短,生长快。经过详细鉴定,作者确认它是端足目、蜾蠃蜚科、蜾蠃蜚属中的一个新种,定名为中华蜾蠃蜚(Corophium sinense sp. nov.)。  相似文献   

10.
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   

11.
Sandy beaches are harsh environments, driving resident arthropod populations to various typical adaptations, particularly behavioural ones. Here we evaluated the effects of seasonal meteorological variability on the behaviour of Talitrus saltator on Berkoukesh beach (N-W Tunisia). The site is characterised by a Mediterranean climate, but is particularly exposed to seasonal winds and storms. The shoreline is in morphodynamic equilibrium. We tested sandhopper Talitrus saltator orientation in April, when sudden rainfall and storms are common, and in June, when as a rule the weather is warm and dry. The results were analysed with circular statistics and multiple regression models adapted to angular distributions, in order to highlight differences in orientation under the various conditions. Depending on the environmental conditions, amphipods from the same population appeared to utilise various orientation strategies as a response to different environmental constraints. The use of a range of behavioural mechanisms (sun-orientation seaward, sun-orientation landward, and phototaxis) resulted in links to the local landscape and to the animals’ life cycle. As a general conclusion, we can infer that the behavioural variability found within the same population represents a response to seasonal environmental fluctuation. Such an increase in variability is likely to develop on a beach in dynamic equilibrium, where landscape references are stable, and a variable behaviour represents a strategy for dealing with environmental fluctuations.  相似文献   

12.
用化学品对藻类毒性测试的标准试验方法,分别研究了硫属元素Se(IV)和Te(IV)单组分对钝顶螺旋藻(Spirulina platensis)的毒性效应,用相加指数法评价了Se(IV)和Te(IV)双组分对螺旋藻的联合毒性效应。结果表明,Te(IV)对螺旋藻的毒性大于Se(IV),其EC50,96h分别为125.2mg/L和36.1mg/L;Se(IV)和Te(IV)的联合毒性效应为拮抗作用,其EC50,96h为103.1mg/L。  相似文献   

13.
分别在两种不同水温条件下,采用静水试验法,进行了Cd2+对菲律宾蛤仔的急性毒性实验,以概率单位法求得Cd2+对菲律宾蛤仔的半致死质量浓度(LC50)。结果表明,在12±0.5℃水温下,Cd2+对菲律宾蛤仔的24h、48h、72h、96h的LC50分别为95.05mg/L、46.87mg/L、32.65mg/L和11.31mg/L;在17±0.5℃水温下,Cd2+对菲律宾蛤仔的24h、48h、72h、96h的LC50分别为70.08mg/L、35.28mg/L、22.36mg/L和14.38mg/L。水温12℃和17℃时,Cd2+对菲律宾蛤仔的96h最大容许质量浓度分别为0.113mg/L和0.144mg/L。Cd2+对菲律宾蛤仔属于高度毒性物质,并且随着水温的升高,Cd2+的毒性作用增强。  相似文献   

14.
口足目系统分类学研究进展   总被引:1,自引:0,他引:1  
程娇  王永良  沙忠利 《海洋科学》2015,39(12):173-177
<正>口足目Stomatopoda隶属甲壳动物亚门Crustacea软甲纲Malacostraca掠虾亚纲Hoplocarida。掠虾亚纲是软甲纲三个亚纲中形态构造最为特殊的一个类群,仅含口足目1目,现生种超过450种,分隶于7总科17科[1]。口足类在世界各大海域广泛分布,但主要分布于热带和亚热带水域,其中在印度-西太平洋热带海域种类最为丰富[1]。口足类是十分重要的海洋底栖甲壳动物,在海洋底栖生物和海岸软泥沙底质群落食物链中占据  相似文献   

15.
Amphipoda are a diverse and important faunal component of deep‐sea habitats worldwide. However, relatively little is known about species that are associated with cold‐water corals, in particular concerning their genetic diversity, population genetic processes, population differentiation, and potential host specificity. We exemplarily investigate these questions studying three pleustid species—Stenopleustes aff. malmgreni (Boeck, 1871), Stenopleustes aff. nodifera (Sars, 1883) and Neopleustes aff. boecki (Hansen, 1888)—that are associated with cold‐water corals and polychaete assemblages along the Reykjanes Ridge southwest of Iceland. We sequenced mitochondrial COI and performed ddRAD to study thousands of nuclear loci. These species and a pair of morphologically cryptic species within Stenopleustes aff. nodifera were consistently delimited by COI and ddRAD. We conclude that all of our studied species are new to science, raising the number of pleustids reported from cold‐water corals to six. Two species were collected only once, and these species exhibited high levels of inbreeding, suggesting little exchange with other populations, which might be a result of strong host specificity. The other two species were wider distributed, with very low differentiation among populations, even between populations separated by 130 km. These species showed signs of recent population expansions, possibly in relation to changes in the cold‐water coral associated ecosystem (e.g., due to glacial cycles and/or volcanic or geothermal activities). They had lower levels of inbreeding and were each associated with three different host coral species, which might facilitate dispersal and gene flow. Our results show divergent population genetic patterns for the studied pleustid species. These might be attributed to the species’ host specificity and highlight important differences among species with seemingly similar life‐styles. Species diversities appear to be greatly underestimated, limiting our abilities to truly assess the vulnerability of the fauna living in these threatened cold‐water coral habitats.  相似文献   

16.
17.
崔冬玲  沙忠利 《海洋科学》2015,39(8):110-115
<正>1鼓虾科简介鼓虾科(Alpheidae)隶属于节肢动物门(Arthropoda)甲壳动物亚门(Crustacea)十足目(Decapoda)真虾下目(Caridea),是一个物种丰富和生态多样性非常高的科[1],至今已建立47属[2],其中仅鼓虾属(Alpheus)就已发现近300种[2-5]。本科中多为穴居或潜伏生活的种类,大部分种生活于热带和亚热带浅海,以印度洋-西太平洋区种类最为丰富[6],少数种生活在寒温带。几乎所有的鼓虾都生活在海底,很少有离开底部  相似文献   

18.
Annual production was calculated for the dominant ampeliscid amphipod Ampelisca mississippiana [Soliman, Y., Wicksten, M., 2007. Ampelisca mississippiana a new species (Amphipoda: Gammaredea) dominated the head of the Mississippi Canyon (Northern Gulf of Mexico). Zootaxa, submitted] at the head of the Mississippi Canyon in the northern Gulf of Mexico. Average densities were 12,094±2499 ind m−2, with secondary production of 6.93 g dry wt m−2 yr−1, based on the “size-frequency method” [Hynes-Hamilton, H.B.N., Coleman, M., 1968. A simple method for assessing the annual production of stream benthos. Limnology and Oceanography 13, 569–573; Menzies, C.A., 1980. A note on the Hynes-Hamilton method of estimating secondary production. Limnology and Oceanography 25(4), 770–773], with a production/biomass (P/B) ratio of 3.11. Growth rates of this magnitude are comparable to available data for freshwater and shallow marine ampeliscids, but are unexpectedly high for deep-ocean habitats. Growth efficiency appeared to be approximately 35% (Growth/Assimilation×100).  相似文献   

19.
在水温18.5~20℃的静水条件下,用4种卤素类消毒剂对刺参幼参进行了急性毒性试验。结果表明,三氯异氰尿酸(trichloroisocyanuric acid,简称TCCA)对刺参幼参的24 h LC50、48 h LC50和安全质量浓度(Cs)分别为33.22、25.32、4.41 mg/L,二溴海因(dibromo dimethyl hydantoin,简称DBDMH)的24 h LC50、48 h LC50和Cs分别为371.17、339.65、85.32 mg/L,聚维酮碘(povidone-iodine,简称PVP-I)的24 h LC50、48 h LC50和Cs分别为3.14、1.450、.09 mg/L,季铵盐络合碘(quaternary ammonium salt-iodine,简称QASI)的24 h LC50、48 h LC50和Cs分别为4.24、2.02、0.14 mg/L。研究表明,4种消毒剂对幼参的毒性大小依次为聚维酮碘>季铵盐络合碘>三氯异氰尿酸>二溴海因。  相似文献   

20.
为了评估大菱鲆(Scophthalmus maximus)耐氨氮性状的遗传参数和为循环水养殖大菱鲆提供科学指导,作者研究了养殖海水中氨氮对4月龄和8月龄大菱鲆的急性毒性效应,同时对比了氨氮对白化和正常个体、雌性和雄性个体的急性毒性效应差别。结果表明:非离子氨对4月龄大菱鲆的24、48、72、96 h LC50分别为2.19、1.94、1.80、1.72 mg/L,对8月龄大菱鲆的24、48、72、96 h LC50分别为3.64、3.02、2.93、2.86 mg/L,非离子氨对4月龄和8月龄大菱鲆的安全质量浓度分别为0.17和0.29 mg/L;氨氮对白化和正常大菱鲆以及雌性和雄性大菱鲆的急性毒性效应均没有显著性差异,研究结果为进一步选育大菱鲆的耐氨氮品系提供科学依据。  相似文献   

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