Paddlefish (family Polyodontidae) are basal Chondrostean ray-finned fish. They have been referred to as "primitive fish" because they have evolved with few morphological changes since the earliest fossil records of the Late Cretaceous, seventy to seventy-five million years ago.  Polyodontids are exclusively North American with the exception of the genus Psephurus, which includes solely the Chinese paddlefish (Psephurus gladius).

Paddlefish (family Polyodontidae) are basal Chondrostean ray-finned fish. They have been referred to as "primitive fish" because they have evolved with few morphological changes since the earliest fossil records of the Late Cretaceous, seventy to seventy-five million years ago.  Polyodontids are exclusively North American with the exception of the genus Psephurus, which includes solely the Chinese paddlefish (Psephurus gladius).