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

Hemigrapsus nudus (Dana, 1851)
Purple Shore Crab
Family: Grapsidae

Species account author: Josephine Hart.
Extracted from Crabs and their relatives of British Columbia.
Photo of species

© Liz Watkinson  Email the photographer   (Photo ID #3963)

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

Species Information

Carapace surface relatively flat and slightly convex anteriorly with a median H-shaped depression. Chelipeds smooth, stout; fingers long and irregularly toothed. Walking legs somewhat flattened, smooth stout and naked.


Carapace: male 48 x 56.2 mm, female 28 x 34 mm.


Variable, especially in small individuals. Large males usually dark purplish red on the surface of the carapace and with pink or yellow granules in a symmetrical pattern of spots; narrow margins reddish with pale violet granules and yellowish streak posteriorly. Chelipeds reddish with purple splotches; palm violet with reddish spots; fingers violet to white and yellow ventrally, and pubescence pale brown. Walking legs dark purple with some red and yellow patches on joints; claw tan. Ventrally lighter. Eyestalk white, red and brown; cornea black. Occasionally one finds an olive green and yellow male.


Upper intertidal, under rocks and gravel.



Yakobi Island (57°57’N, 135°23’W), Lisianski Strait, Alaska, to Turtle Bay, Mexico; intertidal.
Distribution In British Columbia


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.

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: 2024-07-17 4:43:20 PM]
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© E-Fauna BC 2021: An initiative of the Spatial Data Lab, Department of Geography, UBC