Geologic Time Scale: Silurian Period
(443.8 to 419.2 million years ago)
The Silurian Period was first identified by British geologist Roderick Murchison, who was examining fossil-bearing sedimentary rock starta (layers) in south Wales in the early 1830s. He named the sequences for a Celtic tribe of Wales, the Silures, inspired by his friend Adam Sedgwick, who had named the period of his study the Cambrian, from the Latin name for Wales.
About 60% of marine genera were wiped out in the Ordovician-Silurian extinction events. The “Silurian-Devonian Terrestrial Revolution” includes the emergence of vascular plants, fungi, and arthropods (arachnids, myriapods, and hexapods) became fuly terrestrial.
Pridoli Epoch
Late Silurian: 423.0 to 419.2 million years ago
The Pridoli Epoch is the uppermost or end of the Late Silurian Period. It was named after the area Pridoli area of the Deleje Valley on the outskirts of Prague in the Czech Republic.
European Pridoli Epoch Late Silurian: 423.0 to 419.2 million years ago

Name: Pterygotus “finned one or wing animal”
Classification: Order: Eurypterida – Superfamily: Pterygotioidea – Family: Pterygotidae
Locality: Middle Silurian in Europe (British Isles) and Devonian in North America
Time period: Silurian to mid Devonian
Large individuals up to 1.75 meters long
Diet: Carnivore

Name: Eurypterus ”wide wing”
Classification: Eurypterida, Eurypteroidea, Eurypteridae
Locality: Eastern Canada and the United States. Across Europe
Time period: Silurian (Late Llandovery to Pridoli)
Size: 13 centimeters to 1.3 meters long.
Diet: Carnivore
Ludfordian Age/Stage
Ludlow: 423.0 to 419.2 million years ago
The Ludfordian Stage is named after the village of Ludford in Shropshire, England. It marks he end of he upper Ludlow Epoch.
European Ludfordian Stage Ludlow: 423.0 to 419.2 million years ago

Name: Pterygotus “finned one or wing animal”
Classification: Order: Eurypterida – Superfamily: Pterygotioidea – Family: Pterygotidae
Locality: Middle Silurian in Europe (British Isles) and Devonian in North America
Time period: Silurian to mid Devonian
Large individuals up to 1.75 meters long
Diet: Carnivore

Name: Eurypterus ”wide wing”
Classification: Eurypterida, Eurypteroidea, Eurypteridae
Locality: Eastern Canada and the United States. Across Europe
Time period: Silurian (Late Llandovery to Pridoli)
Size: 13 centimeters to 1.3 meters long.
Diet: Carnivore
Gorstian Age/Stage
Ludlow: 427.4 to 425.6 million years ago
The Gorstian Stage of lower Ludlow Epoch was named after the Gorsty village southwest of Ludlow.
European Gorstian Stage Ludlow: 427.4 to 425.6 million years ago

Name: Pterygotus “finned one or wing animal”
Classification: Order: Eurypterida – Superfamily: Pterygotioidea – Family: Pterygotidae
Locality: Middle Silurian in Europe (British Isles) and Devonian in North America
Time period: Silurian to mid Devonian
Large individuals up to 1.75 meters long
Diet: Carnivore

Name: Eurypterus ”wide wing”
Classification: Eurypterida, Eurypteroidea, Eurypteridae
Locality: Eastern Canada and the United States. Across Europe
Time period: Silurian (Late Llandovery to Pridoli)
Size: 13 centimeters to 1.3 meters long.
Diet: Carnivore
Homerian Age/Stage
Wenlock: 430.5 to 427.4 million years ago
The Homerian Stage of the Wenlock Epoch of the Silurian Period of the Paleozoic Era. It is named after the village of Homer, Shropshire near Much Wenlock in England.
Euroean Homerian Stage Wenlock: 430.5 to 427.4 million years ago

Name: Pterygotus “finned one or wing animal”
Classification: Order: Eurypterida – Superfamily: Pterygotioidea – Family: Pterygotidae
Locality: Middle Silurian in Europe (British Isles) and Devonian in North America
Time period: Silurian to mid Devonian
Large individuals up to 1.75 meters long
Diet: Carnivore

Name: Eurypterus ”wide wing”
Classification: Eurypterida, Eurypteroidea, Eurypteridae
Locality: Eastern Canada and the United States. Across Europe
Time period: Silurian (Late Llandovery to Pridoli)
Size: 13 centimeters to 1.3 meters long.
Diet: Carnivore
Sheinowoodian Age/Stage
Wenlock: 433.4 to 430.5 million years ago
The Sheinwoodian Stage of the lower Wenlock Epoch was named after the Sheinwood village, north of Much Wenlock, United Kingdom.
European Sheinowoodian Stage Wenlock: 433.4 to 430.5 million years ago

Name: Pterygotus “finned one or wing animal”
Classification: Order: Eurypterida – Superfamily: Pterygotioidea – Family: Pterygotidae
Locality: Middle Silurian in Europe (British Isles) and Devonian in North America
Time period: Silurian to mid Devonian
Large individuals up to 1.75 meters long
Diet: Carnivore

Name: Eurypterus ”wide wing”
Classification: Eurypterida, Eurypteroidea, Eurypteridae
Locality: Eastern Canada and the United States. Across Europe
Time period: Silurian (Late Llandovery to Pridoli)
Size: 13 centimeters to 1.3 meters long.
Diet: Carnivore
Telychian Age/Stage
Llandovery: 438.5 to 433.4 million years ago
The Telychian Stage of the Llandovery Epoch of the Silurian Period of the Paleozoic Era of the Phanerozoic Eon. The Telychian the Pen-lan-Telych Farm near Llandovery, Powys, Wales.
European Telychian Stage Llandovery: 438.5 to 433.4 million years ago
