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Molecular identification of ascaridoid nematodes from the deep-sea onion-eye grenadier (Macrourus berglax) from the East Greenland Sea 总被引：2，自引：0，他引：2
Esra Kellermanns Sven Klimpel Harry Wilhelm Palm 《Deep Sea Research Part I: Oceanographic Research Papers》2007,54(12):2194-2202
Macrourus berglax from the East Greenland Sea was studied for the presence of ascaridoid nematodes in 2001, 2002 and 2003. The fishes were collected between 278 and 413 m water depth using a benthopelagic net. Based on the amplification of the internal transcribed spacer ITS-1, 5.8S, ITS-2 and flanking sequences (=ITS+), three ascaridoid nematode species were identified. The prevalence of infestation during the 3 years ranged from 42.9% to 62.9% and 22.9% to 40.0% for the anisakids Anisakis simplex (s.s.) and Pseudoterranova decipiens (s.s.), respectively, and from 28.6% to 60.0% for the raphidascarid Hysterothylacium aduncum. A total of 18 specimens, two of each species and examination year, revealed no sibling species, suggesting a limited distribution of other ascaridoid siblings into the deep sea. The ITS-1, 5.8S and ITS-2 sequences of A. simplex (s.s.) from the East Greenland Sea did not differ from previously published sequence data (GenBank) from other regions in the Atlantic and Pacific oceans. The sequences of P. decipiens (s.s.) corresponded most closely to those of specimens from Richardson Bay, western Pacific, and differed in four positions (0.5%). They corresponded least to those of specimens from Japan (1.5%). The sequence data for H. aduncum differed in two positions in the ITS-1 (0.2%) and three positions in the ITS-2 (0.3%) from sequences from Japan. A high genetic similarity between the regions can be explained by (a) extensive final host migration in the case of A. simplex (s.s.), (b) an overlapping distribution of final host populations along the continental shelves for P. decipiens (s.s.) and (c) a low host specificity and large population size in the intermediate and final hosts for H. aduncum. The occurrence of the identified species in the macrourid fish underlines the potential of cosmopolitan ascaridoid nematodes to distribute not only horizontally but also vertically in the deep sea. 相似文献
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Walleye pollock (Gadus chalcogrammus) is one of the popular fish species in Korea and known to frequently harbor anisakid nematodes. Despite many papers regarding walleye pollock having been published, there is no information on the prevalence and distribution of anisakid nematodes from walleye pollock in Korean waters. We investigated 716 walleye pollock caught from Goseong, the East Sea of the Korean Peninsula during May 2015–December 2016. In total, 1,085 nematodes were collected and subsequently identified by PCR-RFLP analysis of internal transcribed spacer region of ribosomal DNA. The prevalence and mean intensity of anisakid nematodes was 63.6% (68/107) and 4.4 larvae/fish (297/68) in samples of 2015, and 21.5% (131/609) and 6.0 larvae/fish (788/131) in samples of 2016. The most abundantly isolated anisakid nematode was Anisakis simplex (Rudolphi, 1809) (73.5%, 798/1,085), followed by Contracaecum osculatum (Rudolphi, 1802) (3.1%, 34/1,085), Hysterothylacium aduncum (Rudolphi, 1802) (2.9%, 31/1,085), Anisakis pegreffii (Campana-Rouget and Biocca, 1955) (1.4%, 15/1,085), and a hybrid genotype (0.4%, 4/ 1,085). The mitochondrial DNA cox2 gene sequences of randomly selected A. simplex showed the highest similarity (99.5%–98.8%) with those from chub mackerel (Scomber japonicus) in Japan or from chum salmon (Oncorhynchus keta) in Korea. The mtDNA cox2 gene sequences of C. osculatum showed the highest similarity (99.0%) with those from bearded seals in Japan. All of these results give us clues to the geographical distribution, migration route and prey items of walleye pollock caught off Korea. Further extensive analyses will be necessary to get more information on the biology of Korean walleye pollock. 相似文献
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《African Journal of Marine Science》2013,35(1):177-183
Nine stages and substages of post-, inter- and premoult were distinguished in the West Coast rock lobster Jasus lalandii by microscopic examination of the cuticle, epidermal retraction and setal development in the pleopods. The postmoult condition is characterized by progressive thickening of the setal walls and cuticle through to inter-moult. Premoult commences with apolysis (Stage D0), followed by setal development (Stage D1', D1", D1'") and culminates with cuticle deposition (Stage D2), The diagnostic features of the stages are generally similar to those of other decapod crustaceans. 相似文献
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Tenshi Ayukai 《Journal of Oceanography》1986,42(6):487-489
Adult females ofAcartia omorii were allowed to feed on fecal pellets voided by its juveniles (copepodite stages I and II) in a mixture with the diatomThalassiosira decipiens. The rate of filtering of pellets by adult females was 50.3 ±11.5 ml indiv–1 d–1, being twice as high as the rate of filtering ofT. decipiens. 相似文献
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Manoela Costa Brandão Andréa Green Koettker Andrea Santarosa Freire 《Marine Ecology》2013,34(2):171-185
We investigated the effect of interannual variation on the biodiversity and distribution of decapod larvae at Saint Paul's Rocks, an isolated small group of equatorial islands linked to the Atlantic Mid‐Ocean ridge. Zooplankton samples were collected between 2003 and 2005 from a range of different environments off the archipelago. Horizontal surface hauls were conducted in the inlet and at three increasing distances from the archipelago, both in the morning and at night, using a 200‐μm mesh net. Decapod larvae collected included 11 species and 37 individual taxa. Seven of them have not previously been recorded in the area. Samples taken at the shortest distance from the archipelago exhibited a significantly greater abundance than samples taken further away. No significant differences were detected between months in terms of decapod larvae abundance in the inlet. However, in the open ocean at night, the mean abundance was much higher in May and July. Decapod larvae abundance was much higher at night for both the open ocean and the inlet. Brachyuran and caridean larvae exhibited the greatest abundance and frequency in the inlet, mainly represented by the first‐stage larvae of: Grapsus grapsus, Plagusia depressa, Platypodiella spectabilis and Alpheidae. In contrast, Sergestidae holopelagic shrimps were the most abundant and the most frequent larvae in the surface waters of the open ocean. The composition, abundance and distribution of decapod larvae were very similar during the 2 years sampled. Species accumulation curves indicate that even greater diversity exists, demonstrating that long‐term research is important for acquiring accurate knowledge about the biodiversity of dynamic ecosystems such as those at Saint Paul's Rocks. 相似文献
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Eko Setyobudi Chan-Hyeok Jeon Kwangho Choi Sung Il Lee Chung Il Lee Jeong-Ho Kim 《Ocean Science Journal》2013,48(2):197-205
The occurrence of Genus Anisakis nematode larvae in marine fishes and cephalopods is epidemiologically important because Anisakis simplex larval stage can cause a clinical disease in humans when infected hosts are consumed raw. Common squid (Todarodes pacificus) from Korean waters were investigated for anisakid nematodes infection during 2009～2011. In total, 1,556 larvae were collected from 615 common squids and 732 of them were subsequently identified by PCR-RFLP analysis of ITS rDNA. Depending on the sampling locations, the nematode larvae from common squid showed different prevalence, intensity and species distribution. A high prevalence (P) and mean intensity (MI) of infection were observed in the Yellow Sea (n = 250, P = 86.0%, MI = 5.99 larvae/host) and the southern sea of Korea (n = 126, P = 57.1%, MI = 3.36 larvae/host). Anisakis pegreffii was dominantly found in common squid from the southern sea (127/ 140, 90.7%) and the Yellow Sea (561/565, 98.9%). In contrast, the P and MI of infection were relatively low in the East Sea (n = 239, P = 8.37%, MI = 1.25 larvae/host). A. pegreffii was not found from the East Sea and 52.0% (13/25) of the nematodes were identified as A. simplex. Most of them were found in the body cavity or digestive tract of common squid, which are rarely consumed raw by humans. Considering the differenences in anisakid nematode species distribution and their microhabitat in common squid, it remains unclear whether common squid plays an important role in the epidemiology of human anisakis infection in Korea. Further extensive identification of anisakid nematodes in common squid, with geographical and seasonal information will be necessary. 相似文献
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Malcolm R. Clark 《新西兰海洋与淡水研究杂志》2013,47(3):339-363
The food and feeding habits of hoki (Macruronus novaezelandiae), southern blue whiting (Micromesistius australis), javelin fish (Lepi‐dorhynchus denticulatus), ling (Genypterus blacodes), smooth rattail (Coelorinchus aspercephalus), silverside (Argentina elongata), and small‐scaled notothenid (Notothenia microlepidota) sampled from the Campbell Plateau in 1979 were examined. The importance of prey items in the diet has been assessed by an ‘index of relative importance’, which combines measurements of frequency of occurrence, number, and weight of prey. Hoki, southern blue whiting, and javelin fish are pelagic feeders. Hoki preyed largely on natant decapod crustaceans, amphipods, and myctophid and photichthyid fishes. The main prey of southern blue whiting were amphipods, natant decapods, and euphausiids. Javelin fish fed on natant decapods, amphipods, and small squid. Seasonal and regional differences in feeding, and dietary changes with length of fish were evident. Ling, smooth rattail, silverside, and small‐scaled notothenid are predominantly benthic feeders. Ling preyed on natant decapods, macrourid fishes, and small hoki. The diet of rattail comprised natant decapod crustaceans, opal fishes (Hemerocoetes spp.), and poly‐chaetes. Silverside fed almost solely on salps. Salps, amphipods, brachyuran crustaceans, and opal fishes were the main prey of small‐scaled notothenid. 相似文献
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Carole P. McArthur 《新西兰海洋与淡水研究杂志》2013,47(3):537-538
Unidentified trichodinid ciliates (Protozoa: Ciliophora: Urceolariidae) were recorded within the tissues of the New Zealand freshwater eels, Anguilla australis schmidtii (Phillips) and Anguilla dieffenbachii (Gray). Organisms were small, measuring approximately 10 μm in diameter, and it is not known how they enter the eels. This is thought to be the first recording of usually ectoparasitic trichodinids occurring within their hosts. 相似文献
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B. B. Marinovic D. A. Croll N. Gong S. R. Benson F. P. Chavez 《Progress in Oceanography》2002,54(1-4)
Zooplankton abundance and euphausiid community composition were sampled seasonally (spring, summer, fall) within Monterey Bay, California, between 1997 and 1999. Measurements of sea surface temperature (SST), mixed layer depth, and upwelling indices provided concurrent data on physical oceanographic parameters. Both total zooplankton and krill abundance dramatically declined in the summer of 1997 coincident with a rapid increase in SST and mixed layer depth. Changes in euphausiid community composition occurred in concert with the decline in overall abundance. The relative abundance of the southern neritic Nyctiphanes simplex increased from August to November in 1997, the abundance of cold temperate Euphausia pacifica decreased significantly, and that of the northern neritic Thysanoessa spinifera declined dramatically. The sudden appearance of an adult cohort of N. simplex in July 1997 suggests that rapid poleward flow characteristic of coastally trapped Kelvin waves occurred between June and July of 1997. The persistent presence of warm temperate and subtropical taxa in samples collected between August 1997 and October 1998 indicates that this poleward flow continued in 1998. Zooplankton abundance, euphausiid community composition, and physical oceanographic parameters gradually returned to a more typical upwelling-dominated state in the spring and summer of 1998. E. pacifica and T. spinifera abundances gradually increased during the summer and fall of 1998, while N. simplex abundance abruptly declined in the spring of 1998. However, this recovery was confined to a narrow coastal band as a result of the onshore movement of the oceanic waters of the California Current. This was reflected by higher than normal numbers of the oceanic Nematoscelis difficilis within samples collected during the spring and summer of 1998. By the spring and summer of 1999, both zooplankton and euphausiid abundance had increased to the highest levels recorded during the 3-year study. Both E. pacifica and T. spinifera abundance increased relative to 1998 while N. simplex was completely absent in all samples. These changes reflected the cooler, highly productive environmental conditions associated with the 1998/1999 La Niña. 相似文献
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《African Journal of Marine Science》2013,35(2):215-222
Remotely operated vehicle (ROV) video observations were used to document benthic fauna at a hydrocarbon drilling location, at 2 720 m depth, in the poorly studied deep water off northern Egypt. The decapod Chaceon mediterraneus was the most common organism at the site and the only benthic megafaunal invertebrate observed. Three species of fish, Coryphaenoides mediterraneus, Cataetyx laticeps and Bathypterois mediterraneus, were also encountered. These findings confirmed these three species as the deepest-distributed benthic fish in the eastern Mediterranean, and confirmed that the deep Mediterranean, in particular the eastern basin, is one of the world's poorest deep-sea ecosystems in terms of diversity. The behaviour exhibited by the species observed was consistent with their natatory capacity, deduced from their feeding intensity (gut fullness) and diet (mainly suprabenthic prey were consumed), and conservative life strategies adapted to an extremely low energy environment. 相似文献
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Charles McCann 《新西兰海洋与淡水研究杂志》2013,47(4):619-640
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Yesenia Gallegos-Navarro Scott Monks Sergio García-Ibáñez Agustín A. Rojas-Herrera José Luis Rosas-Acevedo 《新西兰海洋与淡水研究杂志》2019,53(3):377-396
Metazoan parasites communities of marine fishes can include both adults and larval stages of several endoparasite groups that use fishes as intermediate or paratenic hosts. The richness and abundance of parasite species larvae that harbour a fish species can therefore be a good indicator of that species’ role as an intermediate host to endoparasite species.
The parasite communities of two small carangid fishes (Selar crumenophthalmus and Decapterus muroadsi) from Mexican Pacific coasts were quantified and analysed. Five hundred sixty-three carangids (S. crumenophthalmus, n?=?402; and D. muroadsi, n?=?161) were collected between April 2014 and April 2018 from three locations. Twenty-four metazoan parasite species were identified in both hosts: five species of Monogenea (adults), eight of Digenea (7 adults and 1 metacercaria), two of Cestoda (larvae), two of Nematoda (one adult and one larva), two of Acanthocephala (adults), and five of Copepoda. Larval helminths numerically dominated the endoparasite communities of both hosts, suggesting that these carangids are important intermediate hosts for several parasite species. Component parasite community richness and species composition differed between hosts, locations, and sampling years. Variations in host feeding behaviour, and body size were considered as important factors influencing these differences. 相似文献
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Adaptation of diet in a changed environment: Increased consumption of lobster krill Munida gregaria (Fabricius, 1793) by Argentine hake 
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下载免费PDF全文 A well‐replicated decadal‐term (2005–2014) stomach content data set was analysed in order to infer inter‐annual fluctuations in the diet of the Argentine hake, Merluccius hubbsi, an opportunistic predator in the San Jorge Gulf (SJG) ecosystem in the Southwest Atlantic. Ten research cruises were carried out each year during January from 2005 to 2014. A total of 18,461 specimens of Me. hubbsi was analysed, of which 6,777 (36.71%) contained food in their stomachs. The diet of Me. hubbsi changed markedly from 2011 onwards, with much greater consumption of the lobster krill Munida gregaria compared to the years before 2011. The frequency of occurrence (%F) of Mu. gregaria in the stomach contents of Argentine hake increased from the year 2009 onwards, most noticeably since 2011, and mostly over the southern region of the SJG. The main predators of Mu. gregaria in the SJG are two species of teleost fish (pink cusk eel, Genypterus blacodes, Argentine seabass, Acanthistius brasilianus) and three Rajidae skates (Zearaja chilensis, Psammobatis spp. and Sympterygia bonapartii), which exhibited decreased catches in the years analysed. The increased consumption of Mu. gregaria by Me. hubbsi, coupled with decreased trends in abundance of the main predators of the lobster krill during the last decade, indicate that top‐down trophic dynamic control occurs in the SJG ecosystem. 相似文献
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R. A. Prestidge 《新西兰海洋与淡水研究杂志》2013,47(1):193-199
In a laboratory study of the ingestion and assimilation efficiency of larvae of Aeshna brevistyla Rambur and Hemicordulia australiae Rambur, ingestion was determined using Cerenkov radiation techniques and assimilation efficiency by a double‐labelled isotope technique. Of each prey item (Daphnia carinata), 30% was not ingested but lost as body fluids and as material within the alimentary canal of the prey. Assimilation efficiency was greater than 70% for both dragonfly species, which appears to be typical for most other invertebrate predators. The efficiency with which 12th‐15th‐instar Aeshna assimilated 14C did not increase with feeding rate, but Hemicordulia increased its efficiency through instars 12–14. When dragonfly larvae were pre‐fed before experimentation, assimilation efficiency decreased in both species. 相似文献
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J. L. McKoy 《新西兰海洋与淡水研究杂志》2013,47(2):171-180
The seasons of settlement of shipworms in Tauranga and Wellington harbours in 1970–72 were studied using Pinus radiata test‐blocks. At Wellington the seasonal abundance of late‐stage shipworm larvae was monitored in the plankton. In Tauranga Harbour Bankia australis, Lyrodus medilobatus, Lyrodus pedicellatus, and Nototeredo edaxspawned and settled predominantly in summer, when water temperatures were above 17–18°C. Bankia neztalia had peak periods of settlement in winter and early summer and there was no correlation of settlement with water temperature. In Wellington Harbour B. neztalia spawned and settled mainly during winter when water temperatures were 11–15°C. Total larval abundance at the 2 test sites in Wellington Harbour was an approximate indication of the relative intensity of settlement, but seasonal larval abundance did not correlate well with seasonal settlement. B. neztalia larvae settled on air‐dried Pinus radiata wood within 6 days of the immersion of the wood. Annual variations in patterns of settlement of shipworms in the 2 harbours are related to variations in water temperatures. 相似文献
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对分布在黄、渤海沿岸的单条胶黏藻Dumontia simplex Cotton的形态结构、生物量、成熟个体比例与成熟个体生物量/总生物量(R/T指数)的变化、温度性质以及rbcL、COI基因序列进行了详细研究。结果表明:(1)10个采集地点的单条胶黏藻藻体直立、扁平或螺旋状,质地胶质黏滑,颜色为红色或紫红色。在大连黑石礁与付家庄采集到的藻体长度和宽度明显高于其他采集地点;(2)藻体由皮层与髓部组成,皮层由4—8层细胞组成,髓部有疏松的根丝细胞。囊果散生,包埋于皮层内,刚发育的囊果较小,色淡,随着藻体生长囊果变大,颜色加深。四分孢子囊侧生在内皮层上,成熟的四分孢子囊呈十字形分裂;(3)4月生物量最大,平均生物量为4.384g/m2。12月至次年6月成熟个体比例逐渐增大,6月达到100%,且均为四分孢子体;(4)单条胶黏藻生长周期为12月至次年6月,属于一年生海藻,温度性质属于亚寒带性;(5)rbcL与COI基因序列分析表明,十个采集地点的样本间无碱基差异,与产自美国单条胶黏藻聚在一起,形成一个独立的分支,均确定为单条胶黏藻。 相似文献
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Larvae of the decapod Crangon uritai were reared in the laboratory in a factorial experiment employing three temperatures (9, 12 and 15 °C) and three salinities (29‰, 32‰ and 35‰) from hatching to the post‐larval stage. The effects of temperature and salinity on survival, intermolt period (IP) and molt increment (MI) were investigated. Larvae from one brood were subdivided into groups of 20 and reared in glass bowls containing filtered sea‐water at a number of temperature–salinity combinations. The reared larvae were transferred daily to the clean bowls prepared with newly hatched Artemianauplii, and number of molts and mortality within each bowl were recorded. The zoeal size (carapace length) was determined from exuvia and dead larvae, and the IP was also recorded. Larvae of C. uritai completed larval development only at 15 °C temperature. The first zoeal stage completed their development at all temperature–salinity combinations and exhibited the highest survival rate. IP at each stage increased with increasing size and greatly decreased with increasing temperature, and intermolt duration (range of days) increased with larval development especially at the lower temperature. Although the MI decreased with increasing size, it was little affected by temperature. This led to a better growth rate with increasing temperature. 相似文献
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We investigated whether trochophore larvae of the polychaete Hesiocaeca methanicola, which lives on exposed ice‐like methane hydrates between 500 and 600 m, could consume near‐bottom picoplankton. In laboratory trials larvae significantly reduced the growth rates of all types of picoplankton, including heterotrophic bacteria, Prochlorococcus sp., Synechococcus‐type cyanobacteria and phototrophic eucaryotes <3 μm. Our findings suggest that these types of plankton may be important food sources for deep‐sea planktotrophic larvae. 相似文献