Achaeus japonicus
Encounter Rate
Spotting Difficulty
Best Season
Year-round
Depth Range
5-25 meters
The orangutan crab is one of Komodo's most charming and peculiar macro finds — a tiny spider crab covered in fine, reddish-orange hair that gives it an uncanny resemblance to its primate namesake. At barely 2 centimetres across, this minuscule crustacean lives exclusively among the polyps of bubble coral, where its hairy body and translucent legs allow it to blend in remarkably well. The hair is not just cosmetic — the crab actively decorates itself by collecting algae, detritus, and coral mucous on its setae to enhance its camouflage. In Komodo, orangutan crabs are found at sites with healthy bubble coral colonies, and spotting one requires either excellent eyes or a guide who knows exactly which coral heads to check. Once located, they are endearing subjects that often wave their tiny claws and rearrange their hairy coats in front of patient observers. Their small size, charming appearance, and association with a specific coral host make them a favourite among macro photographers and critter enthusiasts visiting Komodo.
Did you recently spot a Orangutan Crab?
Share your encounter with the diving community
Average Size
1-1.5cm
Size Range
0.5-2cm
Maximum Size
2cm carapace width
Feeds on plankton and organic particles captured from the water using its hairy legs. Also consumes coral mucous and detritus gathered from its bubble coral host.
The orangutan crab is one of Komodo's most charming and peculiar macro finds — a tiny spider crab covered in fine, reddish-orange hair that gives it an uncanny resemblance to its primate namesake. At barely 2 centimetres across, this minuscule crustacean lives exclusively among the polyps of bubble coral, where its hairy body and translucent legs allow it to blend in remarkably well. The hair is not just cosmetic — the crab actively decorates itself by collecting algae, detritus, and coral mucous on its setae to enhance its camouflage. In Komodo, orangutan crabs are found at sites with healthy bubble coral colonies, and spotting one requires either excellent eyes or a guide who knows exactly which coral heads to check. Once located, they are endearing subjects that often wave their tiny claws and rearrange their hairy coats in front of patient observers. Their small size, charming appearance, and association with a specific coral host make them a favourite among macro photographers and critter enthusiasts visiting Komodo.
This species plays an important role in the marine ecosystem of Komodo National Park. Responsible diving practices help protect these animals and their habitat for future generations.
No encounters shared yet
Be the first to share your sighting of this species!
Look in bubble coral colonies at macro-rich dive sites. Cannibal Rock, Pink Beach, and Wainilu are good options. Your dive guide will know which specific coral heads are hosting crabs.
Answer a few questions and our team will point you towards the perfect match!
Start nowIt's free and takes 2 mins
