Peprilus triacanthus

The American butterfish (Peprilus triacanthus), also known as the Atlantic butterfish, is a butterfish of the family Stromateidae. 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.