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

Ceratostoma foliatum (Gmelin, 1791)
Foliate Hornmouth; Leafy Hornmouth; Thorn Purpura
Family: Muricidae
Photo of species

© Aaron Baldwin  Email the photographer   (Photo ID #2047)

E-Fauna BC Static Map
Distribution of Ceratostoma foliatum in British Columbia
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The leafy hornmouth is a predatory marine rock snail that is found in the East Pacific Ocean from Sitka (Alaska) to San Diego, where it occurs on rocky faces near bivalves and barnacles (which it feeds on). In British Columbia, it is known from along the BC Coast, including the Queen Charlotte Islands, in the waters around Vancouver Island (including Botanical Beach, Bamfield and many records from the Victoria area), Gibsons and West Vancouver.

The leafy hornmouth shell Ceratostoma foliatum is of special interest because of its predominant varices or flanges. Are these for camouflage, stability, defense, or perhaps other things? After considerable research, mainly at the Bamfield Marine Sciences Centre, British Columbia, there is convincing evidence that the varices play a dual role in the life of the snail. Thus, they act both as destabilising devices to favour aperture-down landings during accidental falls through the water column, and also in providing defense from both shell-crushing crabs and swallowing-type sea stars. For more on Ceratostoma and its varices, go to A SNAIL'S ODYSSEY.

Note Author: Tom Carefoot, Department of Zoology, University of British Columbia.

Species Information

Illustration Source: A Snail's Odyssey

Status Information

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

Synonyms and Alternate Names

Murex foliatus Gmelin, 1791
Murex monodon Eschscholtz, 1829
Purpura alata Schumacher, 1817
Triplex pinnata Perry, 1811

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: 2024-05-24 10:34:55 AM]
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