Overview

• Alienacanthus malkowskii, a 365-million-year-old fish, had the longest underbite ever recorded, with its lower jaw being twice as long as its skull.
• The fish, part of an extinct group called placoderms, provides insights into the evolution of vertebrates, particularly the development of jaws and teeth.
• Alienacanthus used its sharp teeth and elongated jaw to catch and trap live prey, possibly using its jaw to confuse or injure its future meal.
• The fish lived during the Devonian period, also known as the Age of Fishes, a time when a variety of fish groups dominated the oceans.
• The presence of Alienacanthus fossils in both Poland and Morocco suggests that migration occurred in the ocean at that time, despite sea level fluctuations.