Das zweite Beinpaar der Gespensterkrabbe ist dicht mit Algen besetzt, die von "Angelhaaren" festgehalten werden, und dient als Tarnbeinpaar; Laufen mit erhobenen Tarnbeinen.

Inachus dorsettensis, like other Majidae, camouflages itself by plucking off pieces of algae or sponges, working them with the mandibles and fixing them to the carapax, to the second legs, and to the coxae of the remaining legs. The second legs are longer and twice as thick as the other ones. The other legs (except the coxae) as well as the chelipeds lack hooked hairs. Supplementory to the masking, Inachus holds its second legs spread horizontal, so that the crab looks like a band of algae from the anterior side. Now and then these legs are raised alternatively and moved slowly forward to the front in an arch shaped path. These movements mimic a swaying tuft of algae in the swells.