Type
Zone
Age range
304–303.7 Ma
Pennsylvanian
Gzhelian
Kasimovian
Streptognathodus simulator
Streptognathodus firmus
Idiognathodus toretzianus
304.00303.98303.96303.94303.92303.90303.88303.86303.84303.82303.80303.78303.76303.74303.72303.70