Kelp humpback shrimp (Hippolyte clarki):
The kelp humpback or eelgrass shrimp is an abundant species found in a variety of habitats. Variable in color, it typically matches the color of the substrate. Specimens found in eelgrass are usually bright green or transparent. Specimens found in the kelp canopy tend to be yellow brown. Easily confused with other hippolytid shrimps, this species is distinct in being our only species that has the carpus ("wrist") of the second walking leg divided into three flexible segments, all other local hippolytids have the carpus divided into seven segments. This species is the only local species that possess both a branchiostegal and a supraorbital spine. Males of this species are half the size of females (or smaller) and are unique in possessing a third walking leg that may be 2/3 the length of the entire body and bearing grasping structures at the end. The specific function of this structure is unknown.
Kelp humpback shrimp (Hippolyte clarki)