Rugose Land Hermit Crab

Coenobita rugosus, the Rugose Land Hermit Crab, is one of the most widespread land hermit crabs in the Indo-Pacific, distributed from the East African coast through South Asia, Southeast Asia, and into the Pacific island chains. It occupies sandy beaches, coastal scrub, and low mangrove margins, ranging far inland along river valleys in humid regions.

Its name references the rugose — rough or textured — surface of the carapace, which ranges from pale tan to vivid blue-purple, making it one of the more colourful coenobitid species. In captivity it requires the same fundamental setup as other land hermit crabs: deep moist burrowing substrate, high ambient humidity, access to both fresh and marine salt water, a wide selection of empty shells, and a varied omnivorous diet.

C. rugosus is hardy and adaptable, tolerating slight fluctuations in temperature and humidity better than some congeners. It is social and benefits from group living. Providing appropriate shell sizes and allowing the crabs to select their own shells is fundamental to their long-term welfare. Painted or varnished shells must never be offered.

Water: 24–30°C; provide both fresh dechlorinated water and marine saltwater dishes simultaneously for osmoregulation. Tank: minimum 60 L terrarium; deep moist sand, coconut fibre; 75–85% humidity; climbing branches; spare shells in variety of sizes. Feeding: omnivore — dried fruit, coconut, shrimp, algae, leafy greens, commercial hermit crab food; feed daily. Breeding: pelagic larvae require open ocean; captive breeding not possible. Compatibility: social; groups of 3 or more recommended; do not mix species; provide abundant shells.