Patera appressa (Say, 1821), an introduced land snail in Ontario, Canada (Mollusca: Gastropoda: Polygyridae)

Robert G. Forsyth, Michael J. Oldham, Frederick W. Schueler


The geographic distribution and habitat of Patera appressa (Say, 1821) in Canada are described. This is a North American land snail native to the southern Appalachians but it has been known, since 1994, from a cluster of sites in Trenton, City of Quinte West, Ontario, where it is presumably introduced. It may no longer be extant at any of the known Ontario sites.


introduced species; geographic distribution; Mollusca; Gastropoda; Polygyridae; Ontario; Canada

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