alligator gar

Alligator gar (Atractosteus spatula) are ray-finned euryhaline fishes related to bowfin in the infraclass Holostei (ho'-las-te-i). The fossil record traces the existence of alligator gars back to the Early Cretaceous over a hundred million years ago. They are the largest in the gar family, and among the largest freshwater fishes in North America. Gars are often referred to as "primitive fishes", or "living fossils" because they have retained some morphological characters of their earliest ancestors, such as a spiral valve intestine which is also common to the digestive system of sharks, and they can breathe both air and water. Their common name was derived from their resemblance to American alligators, particularly their broad snout and long sharp teeth. Anecdotal scientific reports suggest that alligator gars can grow up to in length and weigh as much as ; however in 2011 the largest alligator gar ever caught and officially recorded was long, weighed , and was around the girth. Their bodies are torpedo shaped, usually brown or olive fading to a lighter gray or yellow ventral surface. They do not have scales like other fish, rather they are armored for protection against predation with hard, enamel-like, jagged diamond-shaped ganoid scales that are nearly impenetrable. Unlike other gar species, mature alligator gars have a dual row of large sharp teeth in the upper jaw which they use for impaling and holding prey. They are stalking, ambush predators that are primarily piscivores, but will also ambush and eat water fowl and small mammals that may be floating on the surface.