Activation of NMDA receptors evokes sustained fictive locomotion in the isolated spinal cord of the sea lamprey Petromyzon marinus (P. marinus), but in the river lamprey Lampetra fluviatilis (L. fluviatilis) the ventral root activity is often irregular. A previous study showed that the number of 5-HT immunoreactive fibres, neurones and varicosities are much lower in the spinal cord of L. fluvia...

So far, perch egg strands have been considered unpalatable biological material. However, we repeatedly found egg strands of European perch (Perca fluviatilis) in the diet of European catfish (Silurus glanis) caught by longlines in Milada and Most Lakes, Czech Republic. The finding proves that perch egg strands compose a standard food source for this large freshwater predatory fish. It extends t...

Selection can alter predator-prey interactions. However, whether and how complex food-webs respond to selection remain largely unknown. We show in the field that antagonistic selection from predators and pathogens on prey body-size can be a primary driver of food-web functioning. In Windermere, U.K., pike (Esox lucius, the predator) selected against small perch (Perca fluviatilis, the prey), wh...

Three haemocyte groups were identified in the freshwater crab, Potamon fluviatilis: hyalinocytes, semigranulocytes and granulocytes. The proportion of hyalinocytes was found to be 15%, that of semigranulocytes 54.25% and that of 30.75% granulocytes.

anopheles fluviatilis complex is known to be a vector of malaria in iran. since mosquitoes of this species cover a wide geographical range in iran, they might have evolved into different separated populations. random amplified polymorphic dna polymerase chain reaction (rapd-pcr) assay was used to differentiate geographic populations of this species. dna was extracted from individual mosquitoes ...

Generalist species commonly have a fundamental role in ecosystems as they can integrate spatially distinct habitats and food-web compartments, as well as control the composition, abundance and behavior of organisms at different trophic levels. Generalist populations typically consist of specialized individuals, but the potential for and hence degree of individual niche variation can be largely ...

Dengue represents a serious threat to human health, with billions of people living at risk of the disease. Wolbachia pipientis is a bacterial endosymbiont common to many insect species. Wolbachia transinfections in mosquito disease vectors have great value for disease control given the bacterium's ability to spread into wild mosquito populations, and to interfere with infections of pathogens, s...

DNA barcoding utilizes short standardized DNA sequences to identify species and is increasingly used in biodiversity assessments. The technique has unveiled an unforeseeably high number of morphologically cryptic species. However, if speciation has occurred relatively recently and rapidly, the use of single gene markers, and especially the exclusive use of mitochondrial markers, will presumably...

The near-surface distribution of young-of-the-year perch was observed with a towed upward beaming echosounder system (SIMRAD EK60 with a circular 7◦ transducer). Perch aggregated densely in the epilimnion during daytime and dispersed evenly below the surface at night. Shoaling commenced in late June when perchmetamorphosed from the larval to juvenile stage. Average shoal widthwas 6.6m and avera...