A triggerfish marked with a fine grid pattern, feeding in open water above rock rather than on the bottom.
To 30 cm. Males and females look different enough to be worth separating. Males are straw-yellow to golden with every scale outlined in black, making a honeycomb grid over the body, and the tail is red with a bright blue band inside the margin. Females have the same grid but on a slate-grey to blue ground, and a much duller tail with no red. Both have the deep diagonal grooves on the cheek that the genus is known for.
The outrigger triggerfish is the other eastern Pacific member of the genus, but it lives between 50 and 200 m and divers essentially never see it; it has plain blue lines and no crosshatch. Dark females can read as black durgon at range, and the scale grid and cheek grooves separate them.
It schools in midwater over seaward drop-offs and feeds on plankton, so it is not a bottom-grubbing triggerfish. It lives between 6 and 130 m. Its distribution skips the equator: southern Japan, Hawaii, southern California, Clipperton, Revillagigedo, Easter Island and Pitcairn, but not Cocos or the Galapagos. That makes it a Revillagigedo speciality. It is heavily collected for the aquarium trade.
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.