Perciformes means perch-like. They belong to the class of ray-finned fish and have over 7,000 species in almost all aquatic environments.
They have the widest range of sizes of any order of vertebrates, ranging from the 7 mm Schindleria brevipinguis to the 5 metre Makaira species. They first appeared and diversified in the Upper Cretaceous.
The dorsal and anal fins are divided into front spiny and back soft-rayed portions, which may be partially or completely separated.
The pelvic fins usually have one spine and up to five soft rays, positioned unusually far forward under the chin or under the belly. Scales are usually ctenoid (rough-edged).