Chaetodon striatus is one of 88 members of the genus Chaetodon, which together with 11 additional genera make up the butterflyfishes family (Chaetodontidae) in which a total of 129 species are currently described. This species is found in the western Atlantic Ocean, from the coasts of Massachusetts to Brazil, including the entire Gulf of Mexico and the Caribbean Sea. It inhabits rocky and/or coral bottoms and can be seen at depths of up to 55 meters.
With a short snout, the body of Chaetodon striatus adopts a square to oval shape, with the body compressed laterally. They can reach maximum total lengths of 15 cm. The snout is short and pointed, and at its end there is a small mouth with several bands of small teeth. The dorsal fin is composed of 12 spines and 20 soft rays; the anal fin has 3 spines and 16-17 soft rays. The rear ends of the dorsal and anal fins adopt an angulation and make them look like a continuation of the caudal fin perimeter. The pectoral fins are of moderate size and consist of 14 rays, while the caudal fin is slightly rounded.
The predominant color of the body of Chaetodon striatus is white, with the presence of 2 thick vertical black stripes in the center of its body, one just after the insertion of the pectoral fins, and the second just at the level of the soft region of the anal fin. On the rostrum there is also a black stripe, in this case somewhat thinner than the previous ones, and from the beginning of the dorsal fin and forming a 'C' across the eye to end at the base of the pelvic fins. Both the dorsal and anal fins are black with the outer edge bordered by a thin strip of soft color. On the caudal peduncle there is also another black stripe, which runs towards the dorsal end in a faded manner. Finally, the dorsal fin is white from its caudal peduncle, to later present a black band and end with the outermost edge of white.
Chaetodon striatus feeds mainly on polychaete worms, coral polyps, crustaceans and molluscs, and eggs, scraping the invertebrates with its teeth. Adults may form aggregations of up to 20 individuals, occasionally also with other reef fish species. It is a diurnal species, active during the day; it sleeps at night.
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