A large puffer with contour lines radiating from the eye.
To about 65 cm, pale grey-white covered in a maze of fine dark lines that radiate from around the eye like contours, with a dark patch at the pectoral fin base and dark blotches on the belly. The similar Arothron nigropunctatus is plain with black spots; A. stellatus is white with even black dots and grows larger.
Puffers carry tetrodotoxin in the skin, liver and gonads, which is a hazard to eating rather than to divers, and inflate by drawing water into a specialised stomach when threatened — behaviour a diver should not provoke, since it is stressful to the fish and sometimes fatal. It feeds on sponges, algae, corals and molluscs, moving slowly along the reef, and is one of the easier large fish to approach because it does not flee quickly. Recorded from about 3 to 40 m.
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.