|Silurian||Pridoli||no faunal stages defined||older|
|Subdivision of the Devonian system|
according to the ICS, as of 2017.
The Pragian is one of three faunal stages in the Early Devonian epoch. It lasted from 411.2 ± 2.8 million years ago to 407 ± 2.8 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.
In North America the Pragian Stage is represented by Siegenian or Deerparkian time.
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.
|Agnathans of the Pragian|
|Lochkovian-Emsian||Hunsrück Slate Formation, Germany among others in Europe|
|Lochkovian-Emsian||Wayne Hereford Quarry, England & Podolia, Ukraine|
|Lochkovian-Emsian||Britain & Belgium|
- Kröger, Björn (2009). "Nautiloids before and during the origin of ammonoids in a Siluro-Devonian section in the Tafilalt, Anti-Atlas, Morocco". Special Papers in Palaeontology. 79. ISBN 978-1-405-18770-1.
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