Indo-West Pacific: India, Sri Lanka, Andaman Islands, Thailand, Indonesia, Australia, South China Sea, Philippines, Taiwan, Ryukyu Islands, Japan, Mariana Islands, Minami Tori Shima [=Marcus Island], Palau, Yap, Truk, Pohnpei and Kosrae, Nauru, Kiribati, New Guinea, Solomon Islands, Vanuatu, New Caledonia, Fiji, Tonga, Samoa, Niue, Cook Islands, and Society Islands Replaced by Siganus luridus in the west Indian Ocean.

The species can adopt a number of camouflage patterns involving off-white, pale gray to blackish, and various shades of brown. The basic pattern consists of a labyrinth of narrow bands with upper half vermiculate, the lower ones tend to meander horizontally. This pattern extends to the fins. Iris golden dissected by a chocolate cross. 4-5 irregular off-white bars on caudal peduncle. Scales fine on cheeks, densely packed over lower 2/3 of preopercular region. Midline of thorax without scales between pelvic ridges. Fin spines stout, pungent, venomous. Preopercular angle 87-100 degrees.

Adults inhabit shallow coral reef flats. Found in rivers.