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Ectoparasitic species of the genus Trichodina (Ciliophora: Peritrichida) parasitizing Macedonian freshwater fish

100%
Blazhekovikj-Dimovska D., Stojanovski S.
Acta Biologica
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2020
|
tom 27
2

Specific genomic fingerprints of Escherichia coli strains with repetitive sequences and PCR as an effective tool for monitoring freshwater environments

100%
Baldy-Chudzik K., Stosik M.
Polish Journal of Environmental Studies
|
2005
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tom 14
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nr 5
The Rep-PCR fingerprinting method has been applied to identify genomic diversity of 252 E. coli strains derived in the area of a flowing-water basin. The received results show that applying UPGMA and Nearest Neighbour-Joining clustering methods to statistical analysis of rep-PCR fingerprints has made it possible to discriminate and group the strains, revealing a characteristic structure of E. coli population for particular stands of sample drawing. The proposed procedure of the analysis may be useful for routinely monitoring water quality.
3

Freshwater green algal biofouling of boats in the Kabul River, Pakistan

84%
Khuram I., Ahmad N., Jan S., Barinova S.
Oceanological and Hydrobiological Studies
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2014
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tom 43
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nr 4
4

Introductory studies on the morphology of the genus Cladophora from the Gulf of Gdansk

84%
Plinski M., Jozwiak T.
Oceanological and Hydrobiological Studies
|
2005
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tom 34
|
nr Suppl.3
5

The occurrence of Trichodina domerguei Wallengren, 1897 and Trichodina tenuidens Faure-Fremiet, 1944 [Peritrichia] on three-spined stickleback, Gasterosteus aculeatus L., 1758 found in a brackish and freshwater environment

84%
Ozer A.
Acta Protozoologica
|
2003
|
tom 42
|
nr 1
6

The influence of fragmentation on the growth of Elodea canadensis Michx. in different light conditions

84%
Mielecki M., Pieczynska E.
Polish Journal of Ecology
|
2005
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tom 53
|
nr 2
Plant fragments are commonly noticed in a wide range of freshwater environments. However, data on their further growth remain very scarce. The post-fragmentation growth of Elodea canadensis was analysed in a laboratory experiment in which plants were exposed to different light conditions ranging from 3 to 30 µmol m⁻² s⁻¹. The growth of whole plants (12cm) and fragmented (cut) shoots (apical fragment of 3 cm and middle and lower fragments of 4 and 5 cm respectively) was analysed over 33 days (with measurements of weight and length after 11, 21 and 33 days). In all light treatments both cut and whole plants grew. The growth rates were found to vary greatly over the exposure period. During the first 11 days, whole plants or the fragments thereof exhibited the greatest increases in biomass and length in all light treatments. Following further exposure under no shade and moderate shade, the growth of all plants, although still significant, was visibly more limited. Under conditions of a 90% shade level, 11 days of exposure left both whole and cut plants still alive, but incapable of any further significant increase in length or biomass. Generally, in high light levels cut plants grew more intensively, while in conditions of the most intensive (90%) shade, no differences in growth of these groups of plants were noted or the growth of cut plants was limited to a greater extent. A greater number of new lateral shoots were noted in cut plants than in whole plants. Even in conditions of low light characterized by the poor growth of plant fragments the production of new shoots was still possible. In general, fragments of Elodea canadensis were found to be very efficient at surviving and regenerating under a wide range of light conditions.
7

Microhabitat preferences of spined loach, Cobitis sp. in the Grabia River - multivariation approach

84%
Przybylski M., Zieba G., Marszal L., Dukowska M.
Folia Biologica
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2003
|
tom 51
|
nr Suppl.
8

Long-term changes of mollusc assemblages in bottom sediments of small semi-isolated lakes of different trophic state

67%
Kolodziejczyk A., Lewandowski K., Stanczykowska A.
Polish Journal of Ecology
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2009
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tom 57
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nr 2
331-339
It is a common view that increase of the trophic state of lakes has a negative effect on littoral invertebrate macrofauna, molluscs among them. However, the available data are often contradictory, and the decline of particular species is often observed only at a very pronounced raise in trophic state. The aim of this work was to present the changes of the composition and abundance of bottom malacofauna taking place during last 30 years in five small (area from 0.12 to 1.74 km²), mainly shallow (mean depth from 3.7 to 11.8 m) lakes of different trophic state (eutrophic and mesotrophic), connected by a small river (Masurian Lakeland, Northeastern Poland). The research were conducted in years 1997 and 2006 and were compared with published data, collected in 1976. The trophic state of the lakes studied was still constant during the period of investigations. In the studied lakes the decrease of number of bottom mollusc species was observed in subsequent years. The previously recorded there alien, invasive species, Potamopyrgus antipodarum (J.E. Gray, 1843) and Lithoglyphus naticoides (C. Pfeiffer, 1828) also disappeared. Dreissena polymorpha (Pallas, 1771) remained the dominant species in most of the lakes. These changes were recorded in four eutrophic lakes as well as inone mesotrophic lake. The decline of the species in individual lakes didn’t follow any regularity. Some mollusc species disappeared and value of similarity index between malacocenoses in these lakes decreased. It seems, that the trophic state was not the cause of disappearance of some mollusc species from the studied lakes. However, the effect of frequent anoxia in littoral zone related to eutrophication was raised up as the possible cause. The decline is of long-term character, probably resulting from small size and relative isolation of the lakes, which impede their recolonisation.
9

Three new species of the amoebozoan genus Vexillifera Schaeffer, 1926

67%
Dykova I., Kostka M., Peckova H.
Acta Protozoologica
|
2011
|
tom 50
|
nr 1
10

Larval survival strategy during winter of Chordodes nobilii Camerano, 1901 [Gordiida, Nematomorpha]

67%
Zanca F., De Villalobos C., Rumi A.
Acta Parasitologica
|
2007
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tom 52
|
nr 4
There are numerous open questions concerning the life cycle of Gordiida (Nematomorpha), especially about egg development and viability of larvae during winter, when the temperature of freshwater environments where they inhabit is low. On the basis of experimental studies we demonstrate that egg development of Chordodes nobilii takes 20–25 days at 22°C and 45–55 days at 5°C. We also observed that larvae of C. nobilii obtained from egg strings at 5°C and maintained at that temperature during six months remained inside their egg shells as a survival strategy.
11

The role of river bank habitat in the early life of fish: the example of grayling, Thymallus thymallus

67%
Gaudin P., Sempeski P.
International Journal of Ecohydrology and Hydrobiology
|
2001
|
tom 01
|
nr 1-2
In many rheophilic fish species, young stages with low swimming capacities are confined to lateral habitats protected from the main current. Among these lateral habitats, we defined „dead zones” as small bays with shallow water and slow water current caused by physical structures (obstacles or curves of the bank), but without a clear frontier with the main channel. Nevertheless, a study using two and three dimensional hydraulic models revealed the existence of a transiton zone characterized by a strong velocity gradient between these dead zones and the adjacent channel. Young stages of grayling constitute a good model for the study of the different aspects of the use of these lateral habitats. An approach based on direct observation in the field and on experimentations in an artificial channel allowed a precise description of young grayling sizedependent distribution patterns. The grayling undergoes an ontogenetic shift between larval and juvenile habitats. Larval stages are only found in dead zones: the smallest (15-20 mm) are found very close to the river bank and, with increasing age and size (20-40 mm), they begin to get closer to the transition zone. From a size of 40 mm, an increasing number of individuals is observed in the river channel, holding a benthic feeding station. A diel habitat shift also occurs between feeding habitats of larvae and juveniles and dead zones, where the fish are observed resting on the bottom in very shallow water at night. This points out the importance of lateral habitats as (1) exclusive nursery areas for larvae that use them both by day and by night and (2) resting habitats for juveniles at night.
12

On the biology of Pallitrichodina rogenae gen.n., sp.n. and P. stephani sp.n. [Ciliophora: Peritrichida], mantle cavity symbionts of the giant African snail Achatina in Mauritius and Taiwan

67%
Van As J. G., Basson L.
Acta Protozoologica
|
1993
|
tom 32
|
nr 1
13

The effect of salinity of freshwater crustaceans

67%
Grzesiuk M., Mikulski A.
Polish Journal of Ecology
|
2006
|
tom 54
|
nr 4
Recent advancing industrialization and urbanization have increased salt concentrations in formerly-freshwater habitats. Freshwater animals are being affected, especially those like crustaceans that are unable to emigrate to escape the problem. The effects of increased salinity, first observed at the molecular level, are found to extend to the levels of the individual, population, community and ecosystem. Crustacean morphology, behaviour and life histories may be influenced, with growth rate, and age and size at first reproduction, being disturbed, along with clutch and neonate size. Mortality rates are also elevated where the salt concentration is high, though susceptibility to salt differs both between species and between clones of the same species. The effect may be to modify the composition of crustacean assemblages in terms of the species and clones present.
14

A new species of Hysterothylacium (Ascaridoidea, Anisakidae) parasitic in Zenopsis conchifer (Zeiformes, Zeidae) from Argentinean waters

59%
Rossin M. A., Datri L. L., Incorvaia I. S., Timi J. T.
Acta Parasitologica
|
2011
|
tom 56
|
nr 3
A new species of parasitic nematode, Hysterothylacium spirale sp. nov. (Ascaridoidea, Anisakidae), is described based on specimens collected from the intestine and pyloric caeca of the silvery john dory Zenopsis conchifer (Lowe) (Zeiformes, Zeidae), from the Argentinean Shelf (35°05′–40°46′S, 53°03′–58°07′W). Among the 66 valid species described so far in the genus, the new species most closely resembles H. zenis (Baylis, 1929). Both species, apparently specific for fishes of the family Zeidae, share the shape of the dorsal lip, the long expanded lateral alae originating from subventral interlabia and the ornamentation of the tail tip, as well as general morphometry. The combination of these shared features distinguishes both species from all congeners so far known. However, the new species is distinguishable from H. zenis by having shorter interlabia, and consequently the lateral alae originating more posteriorly, shorter spicules, a smaller number of postcloacal papillae and the presence of two pairs of double postcloacal papillae.
15

The occurrence of epibionts of Gordiida [Nematomorpha] in Catamarca, Argentina

59%
De V. C., Salas L., Zanca F., Atencio A.
Acta Parasitologica
|
2010
|
tom 55
|
nr 3
281-285
The presence of larvae and pupae of the genus Metrichia (Trichoptera, Hydroptilidae), larvae of the genus Macrelmis and Phanocerus (Coleoptera, Elmidae), three diatom genera Achnanthes, Cocconeis, Gomphonema, and some specimens of very small diatoms that could not be determined to species or genus level, were recorded for the first time as epibionts for Chordodes brasiliensis (Gordiida, Nematomorpha). Such epibionts were found on the body surface of this species of hairworms, captured from El Tala stream, Catamarca, Argentina.
16

The sorption and removal of heavy metals by algal biomasses

51%
Pawlik-Skowronska B., Pirszel J., Skowronski T.
Oceanological Studies
|
1998
|
tom 27
|
nr 1
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