We find this amphipod amoung blades of the green alga Ulva, low intertidal, where it is beautifully camouflaged. Note the prominent compound eye. The bright red color is due to the visual pigment rhodopsin, present in all known animal photoreptors.
In many of our images of this species, the crab is almost undistinguishable from the background being completely covered with algae and invertebrates. This individual, in contrast, apparently covered with tunicates, stands out well posing on Corynactis anemones. Dept 16 m.