76 resultados para SPECIMENS

em Aquatic Commons


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Sigara dorsalis belongs to a very closely related group of six species forming the sub-genus Sigara sensu strictu. Each of the six species has a distinct allopatric geographical distribution in Europe. Studies were started on a series of populations in the north west Midlands of England. All the populations examined, except one, contained only males with the typical diagnostic features of S. dorsalis, albeit with considerable variation. One pond near Congleton, Cheshire situated in a permanent-ley pasture and apparently free from pollution contained typical S. dorsalis males but, in addition, many atypical individuals. From one sample of forty-six males, all possessed left parameres with the slight point on the dorsal surface characteristic of S. dorsalis. However, almost half possessed additional morphological features intermediate between S. dorsalis and S. striata.

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The aim of this communication is to briefly review nomenclature in the genus Callicorixa, describe the variation in the dark markings on the posterior legs of all four species, describe alternative diagnostic features, and provide a key to identification based on these alternative features. Attention is also drawn to a small error in FBA Scientific Publication 50 (Adults of the British aquatic Hemiptera Heteroptera: a key with ecological notes).

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There are 34 species of the family Corixidae (Hemiptera Heteroptera) in Britain and Ireland of which Sigara striata and Sigara dorsalis are the only two British representatives. In this article the authors briefly consider a range of diagnostic features that may be used to separate British specimens of striata from dorsalis. Most of these morphological features have been used in keys to the British species of the subgenus Sigara sensu strictu. A scoring system has also been devised to facilitate the identification of individuals from the southeast of England, although it is applicable to the whole of the British Isles, and a new (short) key is presented.

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The beche-de-mer industry in India is a cent percent export oriented industry being confined to south east coast in Palk Bay and Gulf of Mannar in Tamil Nadu. Chemical quality of 180 trade samples of beche-de-mer of four sizes collected from the beche-de-mer curing centres of Ramanathapuram district was studied. Moisture ranged from 6.2 to 24.4% and sand content from 0.11 to 20.42% for all grades. Mean values of sand content are for grade 1=3.47%, grade 2=4.50%, grade 3=3.68%, grade 4=6.87%. Sodium chloride was almost constant for all grades at 5.7%. TVBN values ranged from 10 to 78.4 mg%. 44 laboratory samples of different grades were prepared following trade practice and examined for chemical quality. Mean moisture values are for grade 1=13.4%, grade 2=12.44%, grade 3=12.62%, grade 4=12.08% and mean values of sand are for grade 1=0.70%, grade 2=0.90%, grade 3=1.16%, grade 4=2.15%. The percentage of shrinkage of the animals ranged from 56% to 60% for dried beche-de-mer of 7.5 cm size and above.

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While working on the Smithsonian Biological Survey of the Canal Zone, Mr. E. A. Goldman of the Biological Survey, United States Department of Agriculture, collected specimens of two undescribed subspecies of birds which are characterized below. (Document contains 3 pages)

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PICES in transition: The 3rd inter-sessional Science Board and Governing Council meeting (pdf 0.3 MB) New and upcoming PICES publications (pdf 0.3 MB) PICES hosts GLOBEC Symposium on “Climate Variability and Sub-Arctic Marine Ecosystems” in Victoria (pdf 0.4 MB) First CREAMS/PICES Workshop on East Asian Seas Time-series (pdf 0.4 MB) PICES workshop discusses Oceanic Ecodynamics COmparison in the Subarctic Pacific (OECOS) - a project proposal (pdf 0.3 MB) The state of the western North Pacific in the second half of 2004 (pdf 0.4 MB) The Bering Sea: Current status and recent events (pdf 0.3 MB) Recent trends in waters of the subarctic NE Pacific (pdf 0.3 MB) CFAME workshop on “Developing a working plan for CCCC synthesis” (pdf 0.5 MB) What is winter? (pdf 0.5 MB) The first specimens of Humboldt squid in British Columbia (pdf 0.4 MB) Obituary - Dr. Daniel M. Ware (pdf 0.3 MB) PICES Calendar (pdf 0.3 MB)

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A brief synthesis of the systematics of argentine Stromateidae is given together with a general key and morphological and statistical data based on numerous specimens. The southern limit of the range of Perilus parus is discussed. (PDF tiene 12 paginas)

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The genus Percichthys (Serranidae) includes three nominal species in Argentina, trucha, vinciguerrae and altispinis. The authors of this paper examine materials from: 1: the Río Negro river in its inferior course, in front of Viedma; 2: lake Pellegrini, near Neuquén, where the rivers Neuquén and Limay meet and form the Negro; 3: Plottier, near the place just named; 4: Colorado river, in Fortín Uno; 5: Curacó river, a tributary to the Colorado, now cut into separate sections since years ago on account of the lack of water; this river normally would connect the Colorado with the rivers up to the San Juan where the « trucha » lives; 6: Luro or La Salada lagoon, formed by the Colorado river near its mouth; 7: Argentino lake, in the southern Patagonia. These fishes are known as « trucha criolla » or « native trout » although the old Spanish name was « perca », more appropiate. Percichthys altispinis Regan 1905 is a good species ; it has been re-found in the Colorado river, at Fortín Uno. An illustration of it is given, characters of four specimens and a note on its scales. P. trucha C. V. reveeals itself on close examination as a complex species or linnean species (linneon) ; with several combinations of characters, but even more materials are needed to establish if there are geographical races (subspecies). A new examination of the Chilean materials is required (former authors considered them jointly with the Atlantic versant or Argentine materials). Some of the infraspeciíic forms are prognathous, and low finned ; others, the contrary; the head may be normal, or conical and bony; etc. As to P. vinciguerrae its standing as a valid species is doubtfull; perhaps, with P. laevis Jenyns it is a southern form. In the same reduced habitat (lagoon, or isolated course) diversified forms are present; some show parallelism with those of other places ; it is supposed that they show ecological influences according to the year or season of birth or developpment. A thorough study of the scales is given, with epidological characteristics and general conciusions as to the method of measuring and comparing their « reading». There are some marked differences even in the same habitat.

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With the cooperation of several of the executive departments, and of the Field Museum of Natural History, a party of about 10 naturalists was accordingly sent to the zone, and the results so far accomplished have been very satisfactory. Large collections of biological material have been received, including specimens of a considerable number of genera and species new to science. It also seemed important to determine exactly the geographical distribution of the various organisms inhabiting the Isthmus, which is one of the routes by which the animals and plants of South America have entered North America and vice versa. The estimated cost of the survey which would have to be met by the Institution is $11,000...

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Lionfish (Pterois volitans/miles complex) are venomous coral reef fishes from the Indian and western Pacific oceans that are now found in the western Atlantic Ocean. Adult lionfish have been observed from Miami, Florida to Cape Hatteras, North Carolina, and juvenile lionfish have been observed off North Carolina, New York, and Bermuda. The large number of adults observed and the occurrence of juveniles indicate that lionfish are established and reproducing along the southeast United States coast. Introductions of marine species occur in many ways. Ballast water discharge, a very common method of introduction for marine invertebrates, is responsible for many freshwater fish introductions. In contrast, most marine fish introductions result from intentional stocking for fishery purposes. Lionfish, however, likely were introduced via unintentional or intentional aquarium releases, and the introduction of lionfish into United States waters should lead to an assessment of the threat posed by the aquarium trade as a vector for fish introductions. Currently, no management actions are being taken to limit the effect of lionfish on the southeast United States continental shelf ecosystem. Further, only limited funds have been made available for research. Nevertheless, the extent of the introduction has been documented and a forecast of the maximum potential spread of lionfish is being developed. Under a scenario of no management actions and limited research, three predictions are made: ● With no action, the lionfish population will continue to grow along the southeast United States shelf. ● Effects on the marine ecosystem of the southeast United States will become more noticeable as the lionfish population grows. ● There will be incidents of lionfish envenomations of divers and/or fishers along the east coast of the United States. Removing lionfish from the southeast United States continental shelf ecosystem would be expensive and likely impossible. A bounty could be established that would encourage the removal of fish and provide specimens for research. However, the bounty would need to be lower than the price of fish in the aquarium trade (~$25-$50 each) to ensure that captured specimens were from the wild. Such a low bounty may not provide enough incentive for capturing lionfish in the wild. Further, such action would only increase the interaction between the public and lionfish, increasing the risk of lionfish envenomations. As the introduction of lionfish is very likely irreversible, future actions should focus on five areas. 1) The population of lionfish should be tracked. 2) Research should be conducted so that scientists can make better predictions regarding the status of the invasion and the effects on native species, ecosystem function, and ecosystem services. 3) Outreach and education efforts must be increased, both specifically toward lionfish and more generally toward the aquarium trade as a method of fish introductions. 4) Additional regulation should be considered to reduce the frequency of marine fish introduction into U.S. waters. However, the issue is more complicated than simply limiting the import of non-native species, and these complexities need to be considered simultaneously. 5) Health care providers along the east coast of the United States need to be notified that a venomous fish is now resident along the southeast United States. The introduction and spread of lionfish illustrates the difficulty inherent in managing introduced species in marine systems. Introduced species often spread via natural mechanisms after the initial introduction. Efforts to control the introduction of marine fish will fail if managers do not consider the natural dispersal of a species following an introduction. Thus, management strategies limiting marine fish introductions need to be applied over the scale of natural ecological dispersal to be effective, pointing to the need for a regional management approach defined by natural processes not by political boundaries. The introduction and success of lionfish along the east coast should change the long-held perception that marine fish invasions are a minimal threat to marine ecosystems. Research is needed to determine the effects of specific invasive fish species in specific ecosystems. More broadly, a cohesive plan is needed to manage, mitigate and minimize the effects of marine invasive fish species on ecosystems that are already compromised by other human activities. Presently, the magnitude of marine fish introductions as a stressor on marine ecosystems cannot be quantified, but can no longer be dismissed as negligible. (PDF contains 31 pages)

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Summary: The offshore shelf and canyon habitats of the OCNMS (Fig. 1) are areas of high primary productivity and biodiversity that support extensive groundfish fisheries. Recent acoustic surveys conducted in these waters have indicated the presence of hard-bottom substrates believed to harbor unique deep-sea coral and sponge assemblages. Such fauna are often associated with shallow tropical waters, however an increasing number of studies around the world have recorded them in deeper, cold-water habitats in both northern and southern latitudes. These habitats are of tremendous value as sites of recruitment for commercially important fishes. Yet, ironically, studies have shown how the gear used in offshore demersal fishing, as well as other commercial operations on the seafloor, can cause severe physical disturbances to resident benthic fauna. Due to their exposed structure, slow growth and recruitment rates, and long life spans, deep-sea corals and sponges may be especially vulnerable to such disturbances, requiring very long periods to recover. Potential effects of fishing and other commercial operations in such critical habitats, and the need to define appropriate strategies for the protection of these resources, have been identified as a high-priority management issue for the sanctuary. To begin addressing this issue, an initial pilot survey was conducted June 1-12, 2004 at six sites in offshore waters of the OCNMS (Fig. 2, average depths of 147-265 m) to explore for the presence of deep-sea coral/sponge assemblages and to look for evidence of potential anthropogenic impacts in these critical habitats. The survey was conducted on the NOAA Ship McARTHUR-II using the Navy’s Phantom DHD2+2 remotely operated vehicle (ROV), which was equipped with a video camera, lasers, and a manipulator arm for the collection of voucher specimens. At each site, a 0.1-m2 grab sampler also was used to collect samples of sediments for the analysis of macroinfauna (> 1.0 mm), total organic carbon (TOC), grain size, and chemical contaminants. Vertical profiles of salinity, dissolved oxygen (DO), temperature, and pressure were recorded at each site with a small SeaCat conductivity-temperature-depth (CTD) profiler. Niskin bottles attached to the CTD also obtained near-bottom water samples in support of a companion study of microbial indicators of coral health and general ecological condition across these sites. All samples except the sediment-contaminant samples are being analyzed with present project funds. Original cruise plans included a total of 12 candidate stations to investigate (Fig. 3). However, inclement weather and equipment failures restricted the sampling to half of these sites. In spite of the limited sampling, the work completed was sufficient to address key project objectives and included several significant scientific observations. Foremost, the cruise was successful in demonstrating the presence of target deepwater coral species in these waters. Patches of the rare stony coral Lophelia pertusa, more characteristic of deepwater coral/sponge assemblages in the North Atlantic, were observed for the first time in OCNMS at a site in 271 meters of water. A large proportion of these corals consisted of dead and broken skeletal remains, and a broken gorgonian (soft coral) also was observed nearby. The source of these disturbances is not known. However, observations from several sites included evidence of bottom trawl marks in the sediment and derelict fishing gear (long lines). Preliminary results also support the view that these areas are important reservoirs of marine biodiversity and of value as habitat for demersal fishes. For example, onboard examination of 18 bottom-sediment grabs revealed benthic infaunal species representative of 14 different invertebrate phyla. Twenty-eight species of fishes from 11 families, including 11 (possibly 12) species of ommercially important rockfishes, also were identified from ROV video footage. These initial discoveries have sparked considerable interests in follow-up studies to learn more about the spatial extent of these assemblages and magnitude of potential impacts from commercial-fishing and other anthropogenic activities in the area. It is essential to expand our knowledge of these deep-sea communities and their vulnerability to potential environmental risks in order to determine the most appropriate management strategies. The survey was conducted under a partnership between NOAA’s National Centers for Coastal Ocean Science (NCCOS) and National Marine Sanctuary Program (NMSP) and included scientists from NCCOS, OCNMS, and several other west-coast State, academic, private, and tribal research institutions (see Section 4 for a complete listing of participating scientists). (PDF contains 20 pages)

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Fish were collected weekly in Biscayne Bay using a monofilament gill net set from a small skiff during 20-30 minute intervals. Although weekly sampling took place for 2.5 years, only the data from samples collected from June 1976 to June 1977 were used in this document. Abnormal external conditions of fins and body were observed on each fish and recorded. Fish were returned immediately to their habitats. Fish collected in the time period for this study numbered 3,765 and included 32 species. Of these, 16 species, totaling 3,556 fish, were caught in sufficient numbers (20 or more) to warrant data analysis. Only 3 of the 16 species could be considered relatively unafflicted: Aetobatus narinari (spotted eagle ray), Diodon hystrix (porcupinefish), and Selene vomer (lookdown). More than 80% of the examined specimens of these three species were unaffected. Less than 20% of the specimens of Diapterus plumieri (striped mojarra), Micropogonias undulatus (Atlantic croaker), and Pogonias cromis (black drum) displayed normal conditions. The three most afflicted species were Diapterus plumieri, striped mojarra; Micropogonias undulatus, Atlantic croaker; and Pogonias cromis, black drum. Only 7, 3, and 7% respectively showed no external evidence of disease. Data described in this document were originally tabulated in the mid-1970s, remained unpublished, and are no longer available. This document was based on archived unpublished text, a data summary table, and figures. Most of the text and cited references were the ones used in the original manuscript and no attempt was made to update them. (PDF contains 44 pages)