Appearance
Petrolisthes manimaculis has a red or chocolate colored carapace, tan legs, gray antennae, and long chelipeds (claw-bearing arms) that extend 2-3 times the width of the carapace. The species name manimaculis is derived from the Latin for "spotted hands," due to the pattern of turquoise-blue spots on this species' claws that distinguish it from other sympatric species. Another distinguishing feature is that, unlike P. eriomerus, which has blue coloration at the base of its dactyls (the claw's movable appendages), P. manimaculis has a distinctly orange coloration at the base of its dactyls.