The Bowfin (Amia calva) is a prehistoric fish that has survived for millions of years. It is known for its elongated body, long dorsal fin, and rounded tail. Bowfin can grow up to 36 in... The Bowfin (Amia calva) is a prehistoric fish that has survived for millions of years. It is known for its elongated body, long dorsal fin, and rounded tail. Bowfin can grow up to 36 inches in length and are often found in sluggish waters and swamps across North America. They are voracious predators, feeding on fish, crustaceans, and insects. Bowfin are unique in their ability to breathe both air and water, allowing them to survive in low-oxygen environments.Click here to read more about Bowfin.