Chameleon Crab

Geographical Origin and Habitat: Broadly distributed in the tropical Indo-Pacific, including New Guinea, Indonesia, and various Pacific islands. Inhabits damp coastal forests, mangrove areas, and coastal riverbanks.

Taxonomy: Classified under the Sesarmidae family. Features a squarish, robust carapace, strong walking legs, and well-developed claws suited for climbing on wood and rocks. Grows to 4-5 cm.

Social Behavior: Mainly terrestrial and nocturnal. Can be shy during the day. Best kept in small groups if provided with a spacious land area featuring numerous caves and hiding spots.

Coloration and Sexual Dimorphism: Display color shifts from dark brown and purple to bright yellow-orange based on humidity, temperature, and mood. Males have larger claws and a narrow abdomen.

Tank Setup: Demands a paludarium or humid terrarium with roughly 80% land area and 20% water. Use moist coco-fiber, forest soil, and moss as substrate. Provide plenty of logs and rocks for climbing.

Diet and Feeding: Omnivorous with a preference for plant matter. Consumes fresh fruits, vegetables, dried leaf litter (e.g. catappa), specialized crab foods, and small insects. Ensure diet diversity.

Water Quality: The water section should have clean fresh or slightly brackish water with pH 7.2-8.0. Temperature 22-28°C. Maintain high air humidity levels (70-80%) inside the enclosure.

Compatibility and Tankmates: Never house in a standard aquarium as they will drown. In a paludarium, they can share the water section with small fish or shrimp, though the crab may occasionally hunt them.

Aquarium Breeding: Extremely difficult. Females carry eggs, but larvae require marine or brackish water conditions to develop and metamorphose, which is highly complex in home setups.

Risks and Diseases: Low humidity causes fatal molting issues and dehydration. Extremely sensitive to pesticides, land fertilizers, and copper inside the water section.