A bristled, humpbacked shrimp on a wire coral, patterned to match the host's banding.
A small commensal shrimp to about 2 cm with a distinctly humped back, a short rostrum and a covering of blunt spines and bristles on the carapace and abdomen that break its outline against the host. Colour follows the wire coral it sits on, usually white to pale brown with darker bands or saddles that line up with the banding of the coral itself. The other shrimp regularly found on wire corals, Pontonides ankeri, is smaller, smooth-bodied and translucent with fine coloured bands, without the spines or the humped profile; that difference is the quickest way to separate the two, and both may occupy the same coral.
Lives on wire corals of the genus Cirrhipathes and on related sea whips and gorgonians standing on sand and rubble slopes, usually singly or in pairs, feeding on mucus and trapped particles from the host. Recorded from about 10 to 35 m and generally on the deeper part of a slope where the whips are tallest. The shrimp keeps to the shaded side of the coral and rotates round the stem as the observer moves, which is the standard difficulty in photographing it; taking hold of the whip to stop the rotation damages the host and usually makes the shrimp move further off, so the animal is more often worked by following it round. The species was described from Zanzibar and is widespread through the Indo-West Pacific, and it is a routine find on muck slopes across the Coral Triangle.
Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.