Runs a station that fish queue at, and cheats on its clients when it can get away with it.
A slender wrasse to about 11 cm, white in front shading to blue behind, with a black stripe that runs from the snout to the tail and broadens as it goes. Juveniles are black with a single electric blue dorsal stripe. It holds a fixed site — a coral head, a piece of wreckage, a rubble outcrop — and advertises with a bobbing dance, and client fish arrive, hold still and open their mouths and gills to be worked over.
The relationship is genuinely mutual and also genuinely negotiated. Cleaners prefer client mucus to parasites, and a cleaner that takes a bite of mucus makes the client jolt and sometimes leave; they cheat less on clients that can swim off to a rival station, more on captive ones, and they give a better service when another fish is watching. Pairs are a male and the largest female, and the female changes sex if the male is lost. Recorded from the shallows to about 40 m, and on muck sites the station is as often a bottle or a tyre as a coral head.
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.