The Pragian is one of three faunal stages in the Early Devonian Epoch. It lasted from 410.8 ± 2.8 million years ago to 407.6 ± 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. It is named after the city of Prague . The GSSP is located within the Prague Formation at Velká Chuchle , Prague.
2-568: 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
4-460: The next stage. This geochronology article is a stub . You can help Misplaced Pages by expanding it . Siegenian The Siegenian was an epoch of the Devonian period spanning from 411.2 +/- 2.8 To 407 +/- 2.8 Ma. The term overlaps with parts of the internationally recognised Pragian and Emsian epochs, and although once widely used is now deprecated. This geochronology article
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