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

Ceramaster patagonicus (Sladen, 1889)
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Family: Goniasteridae
Photo of species

© Neil McDaniel  Email the photographer   (Photo ID #15873)

E-Fauna BC Static Map
Distribution of Ceramaster patagonicus in British Columbia
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Family Description

Flat body. Prominent marginals; the supero- and inferomarginals are similar. The aboral plates are flat or paxilliform, bearing granules, low stumps or spines. Only the radial areas have papulae. Pedicellariae are generally present. The tube feet have suckers.

Species Information

Click on the image below to view an expanded illustration for this taxon. If more than one illustration is available for a species (e.g., two subspecies may be illustrated) then links to the separate images will be provided below.

Ceramaster patagonicus is pentagonal in shape and up to 8.2 cm in greatest radius, often with the aboral surface swollen and soft to the touch in living specimens. It is creamy orange to red-orange on the aboral side and pale yellow orally. The ratio of arm to disc ranges from 1.3 to 1.7. C. patagonicus has regular hexagonal aboral plates on the radii of the arms, and square or rhomboid plates between the radii. Each aboral tabulate plate is covered with 12 to 15 marginal granules and 4 to 12 central granules; a few plates bear spatulate pedicellariae. The marginals are massive and the granules crowded together. The oral intermediates are four sided, with granules and pedicellariae similar to those on the aboral plates. The adambulacrals have 3 to 5 robust spinelets on the edge of the furrow; distal to these on the oral surface is a longitudinal row of 2 or 3 short, stubby spinelets and then 5 to 8 irregular granules. The mouth plates have 8 or 9 blunt, prismatic marginal spines.

Similar Species

Ceramaster patagonicus is larger than C. arcticus, and it has more granules on the aboral tabulate plates and more furrow spines.



Ceramaster patagonicus (including subspecies patagonicus and fisheri) ranges from the Bering Sea to Cape Horn, South America, in depths of 10 to 245 metres. It is found on rocks or mud. Within diving depth, it is common in some British Columbia inlets, but uncommon in the Strait of Georgia and exposed locations.

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

Ceramaster patagonicus Fisher, 1911
Pentagonaster patagonicus Sladen, 1889

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: 2024-06-22 4:10:15 PM]
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© E-Fauna BC 2021: An initiative of the Spatial Data Lab, Department of Geography, UBC