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Which body features are common among perciform fishes?

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Bluefin tuna swimming underwater in a group, with silvery bodies and streamlined shapes, near Japan. — perciform Bluefin tuna (*Thunnus thynnus orientalis*) in the waters near Japan.

Due to the immense diversity within the order Perciformes, which comprises over 6,000 species of bony fishes, defining universal characteristics is challenging. However, many perciforms share several common anatomical features:12

Common Anatomical Features

Spiny Fins: Most perciforms possess spines on their dorsal, anal, and pelvic fins. The dorsal fin is typically divided into two sections, with the anterior portion supported by spiny rays, which are thought to have evolved for defense.1
Pelvic Fin Position: The pelvic fins are generally located directly below or slightly ahead of the pectoral fins. This positioning provides these fishes with a significant advantage in maneuvering over short distances.1
Protrusible Jaws: A common trait among the group is the presence of protrusible jaws, which allow for a variety of specialized feeding behaviors. The structure of these jaws and the associated teeth—ranging from sharp, piercing canines in piscivores to chisel-like incisors in herbivores—are highly adapted to the specific diet and environment of each species.1