Sponge Crab (Marcocoeloma trispinosum)

The Decorator Sponge Crab (Marcocoeloma trispinosum) is a fascinating and cryptic crustacean known for its unique habit of carrying sponges, shells, or other debris on its back for camouflage. This small, nocturnal crab has a compact, oval-shaped body covered in fine hairs that help it hold onto its protective covering. It is native to the warm waters of the Caribbean and Western Atlantic, typically found in reef environments and sandy or rubble-covered areas where it hides during the day.

Decorator Sponge Crabs are peaceful scavengers that help keep the aquarium clean by feeding on detritus, leftover food, and organic matter.

They are generally considered reef-safe, though they may inadvertently disturb small corals or fragile structures while moving about. Due to their nocturnal nature, they are most active at night, making them a unique addition to a well-established saltwater aquarium. Breeding in captivity is extremely difficult due to their complex larval development. They thrive on a varied diet, including meaty foods, high-quality pellets, and algae-based options. Providing ample hiding spaces and soft substrate will help them feel secure and exhibit their natural behaviors.