Intertidal Organisms EZ-ID GUIDES


on this species


Cancer oregonensis (Pygmy rock crab)

photo of pygmy rock crab
Copyright © 2005 Mary Jo Adams


This small crab has a carapace width of less than 2 inches.   The rounded carapace is widest at the 7 th or 8 th lateral tooth and unlike other cancer crabs, the carapace lacks angular corners.   The carapace is usually red-brown but color varies; the tips of the claws look like they were dipped in black ink.   Its legs are quite hairy.     Look for this crab low in the intertidal under rocks, hiding in crevices, or tucked away in the otherwise empty shell of a giant barnacle ( Balanus nubilus ).   It is found subtidally to a depth of 1400 feet.


The pygmy rock crab accesses the small barnacles that it preys on by crushing their shells with powerful claws.     Other common names for this crab are hairy cancer crab and Oregon cancer crab.  


The crab most likely to be confused with this species is Lophopanopeus bellus bellus (the black clawed crab) as both are small and have black tipped claws.   To distinguish between the two, look for the 3 lateral teeth along the edge of the carapace of the black-clawed crab.   The pygmy rock crab carapace is more rounded, has more numerous teeth, and has very hairy legs.   


This page was created by Mary Jo Adams on 12/5/05.



photo of pygmy rock crab

photo of pygmy rock crab


photo of pigmy rock crab claws