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

Semibalanus cariosus (Pallas, 1788)
Thatched Barnacle
Family: Archaeobalanidae

Species account author: Ira Cornwall.
Extracted from The Barnacles of British Columbia (1955).

Introduction to the Barnacles of BC

Distribution of Semibalanus cariosus in British Columbia

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Species Information

Description

The size varies greatly up to 1¼ inches in diameter and 2½ inches in height. The normal shell is a steep-walled cone with numerous downward-pointing spines, giving it a "thatched" appearance. When crowded they take on a tubular form and may lack the spines. The base is membranous.

Colour

White in young or uncrowded individuals; otherwise dirty grey.

Distribution

Coasts of Western North America and Japan. At about the quarter-tide level, on rock.

Notes

On the British Columbia coast this is the only large barnacle with a membranous base. It is usually found on the rocks, and much crowded.

Status Information

Origin Status	Provincial Status	BC List (Red Blue List)	COSEWIC
Unlisted	Unlisted	Unlisted	Unlisted

BC Ministry of Environment: BC Species and Ecosystems Explorer--the authoritative source for conservation information in British Columbia.

Taxonomic and Nomenclatural Links

Genetic and lineage information (NCBI Taxonomy Browser)

Additional Photo Sources

Flickr Image Search
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Images from Calphoto

Related Databases

A Snail's Odyssey

General References

A glossary of terms for barnacles
Google Scholar Search

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: 2025-03-22 8:52:18 AM]

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