From the Black Sea to the White Sea: The first record of the invasive mollusk Physella acuta in the extreme north of Europe

Freshwater mollusk Physella (Costatella) acuta (Draparnaud, 1805) was previously known in Eastern Europe from the Black Sea coasts to the southern part of the Baltic Sea basin. In 2015, population of Physella acuta was discovered in Lake Imandra (Kola Peninsula, 67°28′ N, 32°26′ E) in the spillway channel of the Kol’skaya Nuclear Power Plant affected by elevated water temperature. The finding of Physella acuta in the White Sea basin is the northernmost record of this species in Eurasia and the first finding of warm-water snail in the inland waters of Fennoscandia.