Which freshwater fish genus includes the ancient-looking bichirs?

The genus Polypterus includes the ancient-looking freshwater fish called bichirs.

Polypterus contains the true bichirs, a group of African fishes known for their elongated bodies, rows of dorsal finlets, and thick, rhomboid scales. They inhabit slow-moving rivers, floodplains, lakes, and swamps across tropical Africa.

Bichirs can breathe atmospheric air using paired lungs, allowing them to tolerate warm, oxygen-poor water. They also use their pectoral fins to move across the bottom, giving them a distinctive, almost walking appearance.

Bichirs are often described as living fossils because they retain several traits associated with early ray-finned fishes. The ropefish, or reedfish, is closely related but belongs to the separate genus Erpetoichthys. Bichirs are popular aquarium fish because of their unusual shape and ancient lineage.