Species of mollusks of the family Pisidiidae (Mollusca, Bivalvia) in water bodies and watercourses of the north of the right-bank Polissya of Ukraine and characterization of their habitat ; Види молюсків родини Pisidiidae (Mollusca, Bivalvia) у водоймах та водотоках півночі правобережного Полісся України та характеристика умов їх оселення

Despite their small size (from 1.5 to 22 mm), Mollusks of the family Pisidiidae (Mollusca, Bivalvia) play an important role in the freshwater ecosystems of Ukraine although having small size (from 1.5 to 22 mm). They are natural filterers and therefore determine the quality of water in water bodies. Due to the divergence of views among taxonomists and due to the small size of these molluscs, their exact number in water bodies and watercourses of Ukraine is not known. According to the results of our own collections conducted in 2019-2022 in the river basins of the Teteriv, Uzh, Ubort, Sluch, Southern Bug, 18 species of Pisidiidae were found, namely Musculium lacustre Müller, 1774, Sphaerium corneum Linnaeus 1758, S. rivicola Lamarck, 1818, S. nusleus Studer, 1820, S. solidum Normand, 1844, Pisidium amnicum Muller, 1774, P. supinum Schmidt, 1851, P. pseudosphaerium Falve, 1927, P. milium Held, 1836, P. subtruncatum Malm, 1855, P. tenuilineatum Stelfox, 1918, P. obtusale Lamarck, 1818, P. nitidum Jenyns, 1832, P. casertanum Poli, 1791, P. henslowanum Sheppard, 1823, P. personatum Malm, 1855, P. moitessierianum Paladilhe, 1866, P. globulare Clessin, 1873. Species identification was carried out using common European approaches to the systematics of this group of animals on the basis of comparison of morphological characters with those described in the literature. Brief autecological characteristics of the species are also were given. The catastrophic disappearance of molluscs of the family Pisidiidae from water bodies and watercourses of Ukraine has been stated, which is probably happened due to anthropogenic impact and the resulted in the reduction and disappearance of suitable habitats suitable for these species. The lack of molluscs can be Eevidenced for this can be found in by the fact that there were in no cases were of the species found report in the regulated areas, i.e. those located between two dams and that characterized by the absence of current lotic water and significant development of muddy bottom ...