Ornate Butterflyfish

Chaetodon ornatissimus is most easily identified by its color pattern, which helps protect it from predators. Ornate butterflyfish have white bodies with orange to orange-brown oblique bands. They also have two yellow-edged black bars on their head: one runs across the eyes and the other is on the snout, and the tail has two black bars. The size of the ornate butterflyfish ranges from 13 to 18 cm total length (mean ± SD = 16.2 ± 1.4 cm) and pair members are nearly always indistinguishable based on size.

The ornate butterflyfish is widespread throughout the tropical waters of the Indo-Pacific area, ranging from Sri Lanka to Hawaii, the Marquesas, the Pitcairn Islands, North to Southern Japan, South to Lord Howe, and Rapa in the Austral Islands. Over three-quarters of the world's fish species inhabit this region. The environment C. ornatissimus lives in is marine, inshore, tropical (30°N – 30°S, 77°E – 124°W) and reef associated. They tend to live at a depth range between 1–36 meters.

Ornate butterflyfish adults are predominately found in pairs that occupy exclusive territories, including Clearwater lagoons and seaward reefs rich in coral growth (size range ~100–1400 m2). On the other hand, juvenile Chaetodon ornatissimus live in solitary, tend to be shy, and hide in the arms of branching corals for protection. Once juveniles reach breeding age, they form pairs. It is uncommon to find adult Chaetodon ornatissimus without a mate. Pairs also establish a "home range" where they are likely always to be found.