Search results for "Amphipod"
showing 6 items of 126 documents
Growth and production of three macrozoobenthic species in the Gulf of Riga, including comparisons with other areas
1999
Three soft-bottom stations in the southern part of the Gulf of Riga were studied during the period December 1993 to January 1995. The amphipods, Monoporeia affinis and Pontoporeia femorata, and the poychaete Marenzelleria viridis, were analysed for production, using the cohort growth method. Animals were also analysed for carbon and nitrogen content in a CHN-analyser. Based on size measurements, the quantitative data were divided into age-classes and the growth of each cohort was calculated first as wet weight and then converted into carbon and nitrogen content. Total annual production of each species was calculated as well as turnover ratios. The turnover ratio for Monoporeia affinis was e…
Data from: Morphological vs. molecular delineation of taxa across montane regions in Europe: the case study of Gammarus balcanicus Schäferna, 1922 (C…
2015
Mountainous areas are characterized by substantial biodiversity and endemicity due to their complex geological history and habitat fragmentation. Hence, it can be assumed that particularly high species richness can be found in organisms with limited dispersal capabilities that inhabit mountain streams. A number of scientific papers focus on molecular phylogeography or traditional taxonomy of species or species groups inhabiting such habitats. However, there is a lack of studies that integrate morphological and molecular data to identify and delineate cryptic species. For practical reasons, uncovering cryptic diversity is crucial in taxa used in biomonitoring. Distinct species, hard to separ…
Data from: Multidimensionality in host manipulation mimicked by serotonin injection
2014
Manipulative parasites often alter the phenotype of their hosts along multiple dimensions. ‘Multidimensionality’ in host manipulation could consist in the simultaneous alteration of several physiological pathways independently of one another, or proceed from the disruption of some key physiological parameter, followed by a cascade of effects. We compared multidimensionality in ‘host manipulation’ between two closely related amphipods, Gammarus fossarum and Gammarus pulex, naturally and experimentally infected with Pomphorhynchus laevis (Acanthocephala), respectively. To that end, we calculated in each host–parasite association the effect size of the difference between infected and uninfecte…
Sediment quality of the ecoregion Engure, Gulf of Riga, assessed by using ecotoxicity tests and biomarker responses
2014
Pētījuma mērķis bija novērtēt Engures ekoreģiona (Rīgas līča rietumu piekrastes) sedimentu kvalitāti, izmantojot sedimentu ekotoksicitātes testus. Lai noteiktu bioloģiskās atbildes reakcijas uz dažāda veida stresoriem, kā testorganismi pielietotas sānpeldes Monoporeia affinis and Pontogammarus robustoides, un izvēlēti biomarķieri (AChE, GST, GR, CAT, MT), kas noteikti gliemenēs Macoma balthica. Engures ekoreģionu varētu uzskatīt par nepiesārņotu rajonu, jo tā sedimentus raksturo salīdzinoši zemas smago metālu koncentrācijas. Engures ekoreģiona sedimentu ekotoksicitātes testu rezultāti neuzrādīja statistiski būtisku (>20% mirstība) toksisko efektu. Testorganismu izdzīvotība bija robežās no 8…
Selective Fatty Acid Retention and Turnover in the Freshwater Amphipod Pallaseopsis quadrispinosa
2021
Gammarid amphipods are a crucial link connecting primary producers with secondary consumers, but little is known about their nutritional ecology. Here we asked how starvation and subsequent feeding on different nutritional quality algae influences fatty acid retention, compound-specific isotopic carbon fractionation, and biosynthesis of omega-3 and omega-6 polyunsaturated fatty acids (PUFA) in the relict gammarid amphipod Pallaseopsis quadrispinosa. The fatty acid profiles of P. quadrispinosa closely matched with those of the dietary green algae after only seven days of refeeding, whereas fatty acid patterns of P. quadrispinosa were less consistent with those of the diatom diet. This was ma…
Makroäyriäisten (Gammaracanthus lacustris, Mysis relicta, Monoporeia affinis, Pallaseopsis quadrispinosa) vuorokausivaellukset Saimaan Paasivedellä; …
2010
We examined the diel vertical migrations of the macroscopic pelagic relict crustaceans Gammaracanthus lacustris, Mysis relicta, Monoporeia affinis and Pallaseopsis quadrispinosa in the deep Lake Paasivesi basin of the Saimaa lake complex. The samples were collected in October 2006 and 2007 using a Hydro-Bios Multi Plankton Sampler onboard the research vessel R/V Muikku. The study provides information about the day-and-night and year-to-year changes in the vertical distribution of these crustaceans. Regarding G. lacustris we explored if body size (length), sex or maturity have bearing on the individuals' depth preference or possible diel migrations. We noticed that G. lacustris females occur…