Osmoregulation in the euryhaline snail Theodoxus fluviatilis

The euryhaline snail Theodoxus fluviatilis occurs both in freshwater and in brackish water habitats. Individuals of both lineages ("ecotypes") are indistinguishable using conventional genetic markers, but differ slightly in morphological characters and markedly in their responses to salinity changes. We investigate the molecular mechanisms and biochemical pathways that define the ranges of osmotolerance in the two lineages of Theodoxus fluviatilis.