E-Fauna BC: Electronic Atlas of the Wildlife of British Columbia

Allogona townsendiana (I. Lea, 1839)
Oregon Forestsnail
Family: Polygyridae
Species account author: Robert Forsyth.

Photo of species

© Robert Forsyth  Email the photographer   (Photo ID #304)

E-Fauna BC Static Map
Distribution of Allogona townsendiana in British Columbia
Details about map content are available here.


The Oregon Forestsnail is restricted in distribution in British Columbia to the southwestern corner of the province. It is found typically in woods dominated by Bigleaf Maple (Acer macrophyllum) and is frequently associated with seepage areas. It is often associated with stinging nettle (Urtica dioica). This species is hermaphroditic, lays eggs, and may be slow-maturing and long-lived.

Species Information


This species is most similar to Allogona ptychophora but differs in being larger and has coarser, more irregular axial riblets below the sutures and is frequently sculptured with fairly strong malleations.


Large, heliciform, brown or yellow-brown, with lighter coloured, irregular ribs; periostracum never hairy; lip thickened and expanded, white; aperture without denticles.




Global Distribution

BC to northwest Oregon.

BC Distribution

Fraser Valley; one isolated location on southeast Vancouver Island (Forsyth 2004; map data).



Genus name derived from the Greek "allos" meaning "other" or "different" + "gona" , "genitalia"; the gender is feminine. The species is named after John Kirk Townsend (1809–51), the Philadelphia physician and naturalist who accompanied Thomas Nuttall on the 1834–35 Wyeth Expedition across the Rockies to Fort Vancouver on the Columbia River.

Status Information

Origin StatusProvincial StatusBC List
(Red Blue List)
NativeS2RedE (Apr 2013)
BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Additional Notes

Recommended Reading

Forsyth, Robert G. 2004. Land Snails of British Columbia. Handbook. Royal BC Museum, Victoria.

Additional Range and Status Information Links

Additional Photo Sources

General References

Recommended citation: Author, Date. Page title. In Klinkenberg, Brian. (Editor) 2021. E-Fauna BC: Electronic Atlas of the Fauna of British Columbia [efauna.bc.ca]. Lab for Advanced Spatial Analysis, Department of Geography, University of British Columbia, Vancouver. [Accessed: 2024-04-21 7:41:51 PM]
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© E-Fauna BC 2021: An initiative of the Spatial Data Lab, Department of Geography, UBC