Gar bodies are elongated, heavily armored with ganoid scales, and fronted by similarly elongated jaws filled with long sharp teeth. Their tails are heterocercal, and the dorsal fins are close to the tail. As their vascularised swim bladders can function as lungs,most gar surface periodically to take a gulp of air, doing so more frequently in stagnant or warm water when the concentration of oxygen in the water is low. As a result, they are extremely hardy and able to tolerate conditions that would kill most other fish.

All the gars are relatively big fish, but the alligator gar is the biggest.

Gar tend to be slow moving fish except when striking at their prey. They prefer the shallow and weedy areas of rivers, lakes, and bayous often congregating in small groups. They are voracious predators, catching their prey with their needle-like teeth, obtaining with a sideways strike of the head. Gar feed extensively on smaller fish and invertebrates such as crabs. Gar are found across all of North America. Although gar are primarily found in freshwater habitats several species enter brackish waters and a few are sometimes found in the sea.

Gar in Oklahoma