Fish of this species are usually deep-bodied, flattened sideways, and somewhat circular or rounded, with blunt noses and small mouths with weak teeth. Some other characteristics of this fish are the absence of
ventral fins, one long, continuous
dorsal fin, long
pectoral fins, and tiny,
cycloid scales. The tail fin is nearly as long as the dorsal fin and deeply forked. The American butterfish is similar in appearance to its close relative, the
harvestfish (
Peprilus alepidotus), but can be distinguished by its much lower dorsal and tail fin. This fish is a lead-blue color above with pale sides and a silvery belly. It often has dark, irregular spots. It is generally , though some individuals reach . They can weigh from . ==Distribution and habitat==