Tetragraptus is an extinct genus of graptolites from the Ordovician period.
Species Source: T. akzharensis T. approximatus T. fruticosus T. insuetus
Distribution Fossils of Tetragraptus have been found in Argentina, Australia, Bolivia, Canada (Quebec, Yukon, Newfoundland and Labrador and Northwest Territories), Chile, China, Colombia (near Caño Cristales, Meta), the Czech Republic, France, Morocco, New Zealand, Norway, the Russian Federation, Spain, Sweden, the United Kingdom, and the United States (Alaska, Idaho, Nevada, Utah).Tetragraptus at Fossilworks.org
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