Petalodontiformes ("thin-plate teeth") is an extinct order of marine cartilaginous fish related to modern day chimaera found in what is now the

United States of America The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territo ...

and

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

.Lund, Richard, E. D. Grogan, and M. Fath. "On the relationships of the Petalodontiformes (Chondrichthyes)." Paleontological Journal 48.9 (2014): 1015-1029. Most species are known only from isolated teeth.Dalla Vecchia, Fabio Marco, and Museo Paleontologico Cittadino. "A new petalodont tooth (Chondrichthyes, Petalodontiformes) from the Lower Permian of the Carnic Alps (Friuli, NE Italy)." Bollettino della Società Paleontologica Italiana 39 (2000): 225-228. All fossils range from the

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

to the

Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

, where they are presumed to have died out during the Permian/Triassic extinction event. The two best known species are ''

Belantsea montana ''Belantsea'' (named after a legendary ancestor of the Crow Nation) is a genus of extinct petalodontid cartilaginous fish that lived during the Lower Carboniferous, about 350 million years ago. Its fossils are found in the Bear Gulch Limestone ...

'', from the Carboniferous Bear Gulch,

Montana Montana () is a state in the Mountain West division of the Western United States. It is bordered by Idaho to the west, North Dakota and South Dakota to the east, Wyoming to the south, and the Canadian provinces of Alberta, British Columbi ...

, and '' Janassa bituminosa'', from the

upper Permian The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleoz ...

of Europe, as whole fossil specimens have been found of these two.

References

Carboniferous cartilaginous fish Permian cartilaginous fish Mississippian first appearances Mississippian taxonomic orders Pennsylvanian taxonomic orders Cisuralian taxonomic orders Permian extinctions Prehistoric cartilaginous fish orders {{Paleo-cartilaginous-fish-stub