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The authors investigated the mycoflora developing on the dead specimens of four species of benthos crustaceans. Ninety-five zoosporic fungus species were found to grow on the fragments of crustaceans investigated. Out of these 95 species, 27 are known as parasites or necrotrophs of fish. Four fungus species were recorded for the first in Polish waters.
The analysis of the factors, connected with the different features of particular macrophyte species, determining the spatial distribution of zooplankton communities (rotifers and crustaceans) was purpose of this study. Particular zooplankton species reveal habitat preferences, which reflect variability in the spatial structure of particular macrophyte species, which is connected with different shape, length and width of stems.
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Cercopagis pengoi as an invasive species

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The fishhook waterflea (Cercopagis pengoi) native to the Ponto-Caspian region, is an excellent example of an invasive species. Within one decade from its first appearance, Cercopagis pengoi has colonized nearly the entire Baltic Sea and most of the Great Lakes of North America. The species spread rapidly owing to its ecological and biological profile. The fishhook waterflea is an euryhaline organism marked by a predominance of parthenogenetic reproduction over sexual reproduction. This taxon quickly colonized inhabited ecosystems to create stable populations. The ecological and economic consequences of the species’ appearance are noticeable, but they have not been fully investigated and require further analysis.
Little is known on the effects of nicotinoid pesticides on behavioural and physiological parameters of microcrustaceans. The aim of the study was to determine the effects of three concentrations (25, 50 and 100 mg l⁻¹) of neonicotinoid insecticide Mospilan 20 SP (containing 20% of the active ingredient acetamiprid) on swimming velocity and physiological parameters such as heart rate and thoracic limb activity in Daphnia magna. The results showed that acetamiprid induced concentration-dependent inhibition of swimming velocity and thoracic limb activity after 2 hours of the exposure. The insecticide depressed the heart rate at 100 mg l⁻¹ after 24 hours of the exposure, however stimulation was noted at 25 and 50 mg l⁻¹. The study suggests that neonicotinoids may alter on behavioural and physiological parameters in Daphnia magna thereby increasing susceptibility of these animals to higher predator pressure.
The present paper reports the occurrence of the Chinese mitten crab Eriocheir sinensis H.M ilne Edwards, 1854 in the coastal waters of the Gulf of Gdańsk, and attempts an initial characterization of the crabs occurring in this area.
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It is common knowledge that fish are a nutritious component of a human diet, as they constitute a valuable and desired source of protein and polyunsaturated fatty acids. Crustacea and shellfish, consumed chiefly for their high sensory values, also demonstrate a similar nutritive value as well as provide zinc that improves the functioning of the nervous system. Nevertheless, seafood are likely to pose risk to consumer’s health since they contain a variety of toxins. In addition, the risk is magnified by the fact that those toxins are usually thermo-resistant and cannot be eliminated by such treatments as cooking.
An assemblage of well−preserved spinicaudatan crustaceans (“conchostracans”) is described from lacustrine late Carnian claystone at Krasiejów in southwestern Poland. Their shell microstructure is similar to that in extant spinicaudatans. Five species identified there are assigned to the genera Laxitextella, Menucoestheria (first record in the European Triassic), and Menucoestheria bocki sp. nov. and Krasiestheria parvula gen. et sp. nov. are erected. Specimens of Laxitextella laxitexta are the most abundant, comprising nearly half of the assemblage, those of Menucoestheria bocki one quarter, Laxitextella sp. A, Menucoestheria? sp., and Krasiestheria parvula form a minor component. Their ecological setting was probably similar to Recent relatives: temporary ponds of fresh water. The Late Triassic fauna in the German part of the same basin is closely similar to that in Poland. In Europe, the stratigraphic range of Laxitextella laxitexta is limited to the Middle Keuper (middle–late Carnian).
The experiment, with the use of sand deposit from hygroarenal (shore sand beach wetted by lake waves) of the beach of eutrophic Lake Mikołajskie (Masurian Lakeland, Poland), was performed in order to test the hypothesis that shore sand deposit is the bank of resting forms of ciliate, rotifer and crustacean species. The experiment was conducted over a 38 days period in March-April 2004. Frozen sand taken in winter was exposed in aquariums filled with pre-filtered (GF/C) lake water in stable temperature (20ºC), oxygen saturation and 12:12 light/dark conditions. Samples (three replicates) were taken each day. A total number of 44 ciliate, 59 rotifer and 9 crustacean taxa were identified during the studied period. Resting forms of different species and/ or taxonomic groups developed in different time and it may be the result of different strategies in colonization of new habitats. Organisms forming resting cysts such as ciliates (11 species) and bdelloid rotifers appeared after the first day of the incubation whereas organisms hatching from resting eggs (monogonont rotifers and crustacea) were observed from the 2nd-3rd day of the experiment. The numbers of all the studied groups of organisms increased gradually and then strongly decreased indicating probably nutrient and/or organic matter limitation. The highest numbers of ciliates (731 ind. cm⁻² of sand) was found on the 5th day, rotifers (987 ind. 100 cm⁻²) on the 23rd day, cladocerans (60 ind. 100 cm⁻²) on the 21st day and copepods (30 ind. 100 cm⁻²) on the 33rd day of the experiment. The results of this study suggests that shore sand deposits being the temporal refugium for the small-bodied invertebrates transported here with the wave action may also play an important role as the transfer for their further dispersal in addition to postulated ways of expansions such as wind, rain, animals and surface runoff.
The trace fossil Spongeliomorpha iberica locally occurs in the Tortonian (Upper Miocene) marine strata of the Fortuna basin in southeastern Spain, and its excellent preservation state allows a reliable reconstruction of its main morphologic features. The burrow systems are branched (but not anastomosing), and they include numerous, short, blind tunnels. The burrow walls are strongly ornamented with bioglyphs displaying a rhomboidal pattern, consisting mostly of individual “Y”−shaped scratches. Smaller, secondary bioglyphs consist of sets of less incised transverse scratches. These features allow us to assign the ichnospecies to a decapod crustacean, most likely an alpheid or thalassinidean shrimp. The burrow apparently served as a refuge for the inhabitant, which fed upon microorganisms growing on the walls of the burrow by means of scraping the interior surfaces with the maxillipeds or other mouth parts. It is also likely that the shrimp used the multiple blind tunnels to store organic material (probably plant detritus) to be used for later consumption. The crustaceans colonized mud firmgrounds, which were formed by erosion during a rapid sea−level fall. Thus, the burrows occur in direct association with erosional regressive surfaces and therefore are good stratigraphic indicators of abrupt paleoenvironmental change.
The article shows the results of studies on the influence of heavy metal ions (manganese, nickel, lead) on the viability and metabolic enzyme activity of marbled crayfish Procambarus virginalis (Lyko, 2017) (Decapoda). Due to the fact that marbled crayfish got into the reservoirs of the Dnipropetrovsk region in 2015, it was necessary to study the possibilities of its adaptation to environmental factors of reservoirs for further prediction of its distribution or even acclimatization under conditions of toxicological contamination of the ponds of the steppe Prydniprovya. In the experiment with marbled crayfish, chronic effects of various concentrations of heavy metal ions on the physiological state and enzyme activity were investigated. The obtained results showed that among the investigated heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. According to the results of the research, significant changes were noted in the individual biochemical parameters of marbled crayfish under the influence of manganese, lead and nickel ions. The most significant changes in the activity of lactate dehydrogenase were detected in muscle tissues affected by manganese and nickel ions. A significant decrease in the activity of succinate dehydrogenase in muscle of marbled crayfish was determined after the action of heavy metal ions. Investigation of changes in the activity of alkaline phosphatase under the influence of the ions of manganese, lead and nickel has its own characteristics, which indicates certain violations in the tissues of cell membranes. Changes in the activity of enzymes were also reflected in the overall protein content. In conclusion, changes in these parameters may indicate a rapid biochemical response of crustaceans to the toxic effects of heavy metals.
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