Ecological Risk Screening Summary - Lister's River Snail (Viviparus contectus) - Uncertain Risk

Species that are considered uncertain risk need a more in-depth assessment beyond the Risk Summary to better define the species’ risk to U.S. environments.

Viviparus contectus, Lister’s River Snail, is a freshwater snail native to most of Europe, from the United Kingdom east to Estonia and Turkey. Viviparus contectus has not been reported as introduced outside its native range and there is no indication this species is in trade outside its native range. The history of invasiveness for this species is classified as No Known Nonnative Population. The overall climate match to the contiguous United States was High, with high matches particularly concentrated in the Great Lakes and central Appalachian regions and scattered throughout the West. All States had high individual climate scores except Florida, with a medium individual climate score. The certainty of assessment is Low due to the lack of information on introductions and trade as well as the difficulty in distinguishing this species from similar species. The overall risk assessment category for Viviparus contectus is Uncertain.