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

Carapace: shield longer than broad. Eyestalk stout; cornea not dilated. Right cheliped shorter than walking legs; carpus and hand with numerous granules and lateral margins beaded; outline of hand semi-oval. Left cheliped smaller than right with ventral margin of merus cut into strong teeth. 1st and 2nd walking legs stout and setose; dactyl slightly shorter than propodus and with stout movable spines ventrally; claw strong and curved. Propodus and dactyl of left 2nd walking leg (3rd pereiopod) with spines and granules ventrally. This is also found in several other intertidal species and the function does not seem to be known. It may be useful for gripping rock faces.

Shield length: male 8 mm.

Carapace mottled blue, brown and green or black with 5 opaque white stripes, the central 3 running from the rostrum to the posterior margin, the other 2 postero-laterally. Right cheliped with ischium olive green dorsally and blue ventrally; merus and carpus olive green with red granules; palm greenish brown with red and white-tipped granules; fingers blue to white with orange tips. Left cheliped similar but more orange on finger tips. 1st and 2nd walking legs olive green to brownish green with dark red striae and an irregular china blue band margined with a narrow red brown band; dactyl china blue with a thin red mid-lateral stripe on both faces and, on dorsal ridge, a patch of orange and of white terminally; claw dark. Eyestalk red brown and olive green with white band distally; cornea black with white flecks forming concentric circles. Antennal flagellum translucent red.