Fossil range: Lower Carboniferous - Permian
| Scientific classification
Petalodontiformes ("petal or flattened teeth") is a group of extinct marine cartilaginous fish related to modern day Chimaeras found in what is now the United States of America and Europe. With a very few exceptions, they are known entirely from teeth. All fossils range from the Carboniferous to the Permian, where they are presumed to have died out during the Permian/Triassic Extinction Event.