Since the adoption of the decree N° 927-N from, the baseline studies have been initiated in the six river basin management areas established in the RA. Thus, the current work aims at contributing to the establishment of principles and a relevant and cost-effective biological monitoring tool for the RA aquatic ecosystems, through the development of a simplified multimetric index (MMI). However, the main goal remains unaccomplished, as the hydro-biological monitoring tools are not properly developed. The Government of the Republic of Armenia (RA) strives to ensure the measures to achieve good ecological status for Armenian surface water bodies.
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pennigerum, with its unusual nymphs and remaining populations in naturally dynamic river courses, can serve as a flagship species promoting the preservation of ecological integrity in European rivers. We propose that Europe's rarest mayfly P. Flagship species were first designated in the 1980s, when charismatic species with high habitat requirements such as the Bengal tiger or the giant panda, but also invertebrates are used to communicate conservation and protection needs.600-bp fragment of the mitochondrial cytochrome c oxidase I gene. This study showed that nymphs from the Vjosa and upper Volga rivers, two relatively natural watercourses 2,000 km apart, are morphologically indistinguishable, and show no variation across a ca.Prosopistoma pennigerum is currently known from only three European rivers, all with gravel substrates, naturally dynamic discharge regimes, summer-warm water temperatures, and little human pressure. This study evaluated general habitat characteristics and human pressures for historical and current records of this rare species.Formerly common in large rivers, it has been extirpated from central Europe over the last century. Prosopistoma pennigerum is a rare European mayfly with conspicuous nymphs.
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Relatively little is known about their ecology, but past and extant distribution patterns indicate an association with undisturbed conditions. They occur in the Palaearctic (nine species), the Oriental (12 species) and the Afrotropic as well as Australian regions (six and two species, respectively). Nymphs of all 29 described Prosopistoma species share a conspicuous synapomorphy: a round mesonotal shield, the carapace.