The living members of the order are all in a single family Lepisosteidae with seven species in two genera. While fossils indicate that some extinct species were marine, the living types are all in the fresh waters of eastern North America, Central America, and the Caribbean islands.
Gar bodies are elongate, heavily armored with ganoid scales, and fronted by similarly elongate jaws filled with long sharp teeth. Tails are heterocercal, and the dorsal fins are close to the tail.
All the gars can be large, but the alligator gar Atractosteus spatula is the champion, specimens having been recorded up to 3 meters in length.
Gar flesh is edible, and sometimes available in markets, but unlike the sturgeons that they resemble, the gars' roe is poisonous.