• Permian of United States (1: Alaska collection)

• Carboniferous of United States (1: Colorado)

• Devonian of Canada (2: Northern Territories, Nova Scotia), China (10), Germany (1), Norway (1), the Russian Federation (7), United States (16: Alaska, New York, Pennsylvania, West Virginia, Maryland, and Pennyslvania)

• Silurian of Canada (59: Manitoba, Northwest Territories, Nunavut, Ontario, Quebec), Germany (1), Lithuania (4), Norway (6), the Russian Federation (26), Sweden (9), Ukraine (8), the United Kingdom (5), United States (118: Alaska, California, Indiana, Iowa, Maryland, Michigan, Michigan and Ohio, New York, Ohio, Oklahoma, Pennsylvania, West Virginia, Wisconsin)

• Chazyan of Canada (9: Northwest Territories, Ontario, Quebec), United States (59: New York, Tennessee, Virginia)

• Whiterockian of Canada (7: Newfoundland, Northwest Territories), United States (60: California, Nevada, Oklahoma, Utah, Virginia)

• Arenig of United States (1: Nevada)

• Arenigian of Canada (2: Northwest Territories), United States (2: Utah)

• Ordovician of Argentina (1), Australia (2), Canada (40: Newfoundland, Northwest Territories, Nunavut, Nunvait, Ontario, Quebec), the Czech Republic (1), Greenland (1), the Russian Federation (4), United States (216: Alaska, Georgia, Indiana, Kentucky, Missouri, Nevada, New York, Ohio, Oklahoma, Tennessee, Utah, Virginia, Wisconsin, Wyoming)

• Tremadoc of Canada (1: Northwest Territories)

• Ibexian of United States (3: Nevada)

• Cambrian of the United Kingdom (1), United States (4: Texas)

Total: 689 collections including 813 occurrences