Decorator Crab (Camposcia Retusa)

Decorator Crab
Also Known As: Spider Decorator Crab

Compatibility and Behavior
The Decorator Crab (Camposcia retusa) is the reef's master of disguise, and it builds the costume itself. Its body and long spidery legs are covered in fine hooked hairs, and the crab uses them like Velcro to attach bits of algae, sponge, coral rubble, and whatever else it can find, turning itself into a slow-moving patch of living reef that all but vanishes against the rockwork. Because its look depends entirely on what it picks up, no two are alike, and a single crab will change appearance over time as it swaps out and upgrades its wardrobe. It is a nocturnal, slow-moving scavenger that spends the daylight hours tucked into crevices and does its foraging after lights out. Temperament is the easy part: it is generally peaceful toward fish and larger inverts. The catch is decoration, which is why this one lands at reef safe with caution. While it mostly works with algae, sponge, and detritus, a crab that runs short on materials may pluck small polyps, soft coral tissue, or zoanthids to add to its disguise. Small, delicate corals or frags placed within easy reach can end up as part of the outfit, so it is best suited to robust mixed reefs where a little natural wildness is welcome.

Aquarium Requirements
This crab wants a mature reef with plenty of porous live rock, overhangs, and caves, both for hiding and for raw decorating material. It does well across a wide range of tank sizes, from larger nanos to big systems, as long as there is ample rock structure and stable, reef-quality water. Moderate flow is ideal, letting fine particles and food settle into the crevices it forages rather than blasting it out of hiding. The trick to keeping it off your corals is keeping it supplied: feed small meaty foods like frozen mysis, finely chopped seafood, or sinking pellets, and offer natural materials such as macroalgae or dried seaweed so it has plenty to decorate with. As with the other long-legged climbers, secure loose frags and top-heavy rockwork it might dislodge while exploring at night.

Specifications

Approximate Size: 1.5–3" (body size; overall span larger with legs and decorations)
Diet: Omnivorous scavenger; detritus, algae, sponge, and leftover meaty foods, and may sample soft coral or polyps for decoration
Origin: Indo-Pacific
Care Level: Moderate
Reef Safe: With caution
Temperament: Peaceful
Special Considerations: May harvest small polyps, soft coral tissue, or zoanthids for camouflage when other materials are scarce, so keep it well supplied and avoid placing delicate frags within reach; nocturnal climber that can dislodge loose frags or top-heavy rockwork