Pragian
second stage and age of the Lower Devonian Series / Early Devonian Epoch
The Pragian is one of three faunal stages in the Early Devonian Epoch. It lasted from 413.02 ± 1.91 million years ago to 410.62 ± 1.95 million years ago. It was preceded by the Lochkovian Stage and followed by the Emsian Stage. The most important Lagerstätte of the Pragian is Rhynie chert in Scotland. It is named after the city of Prague. The GSSP is located within the Prague Formation at Velká Chuchle, Prague.
In North America the Pragian Stage is represented by Siegenian or Deerparkian time.
Pragian life
The first ammonoids (order Agoniatitida) appeared in later parts of this stage (at the lower boundary of the Zlichovian stage as it was known in Siberian representations). They were descended from bactritoid nautiloid ancestors, which also appeared in this stage before experiencing evolutionary radiations in the next stage.
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Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated Oct 23, 2025. The linked authority identifier is Q1089625. Authority coordinates are 50.015, 14.373. 1 of 1 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Pragian” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.