Emsian

System/
Period		 Series/
Epoch		 Stage/
Age		 Age (Ma)
Carboniferous Mississippian Tournaisian younger
Devonian Upper/
Late		 Famennian 358.9 372.2
Frasnian 372.2 382.7
Middle Givetian 382.7 387.7
Eifelian 387.7 393.3
Lower/
Early		 Emsian 393.3 407.6
Pragian 407.6 410.8
Lochkovian 410.8 419.2
Silurian Pridoli no faunal stages defined older
Subdivision of the Devonian system
according to the ICS, as of 2017.[1]

The Emsian is one of three faunal stages in the Early Devonian epoch. It lasted from 407 ± 2.8 million years ago to 397.5 ± 2.7 million years ago. It was preceded by the Pragian stage and followed by the Eifelian stage.

During this period, earliest known agoniatitid ammonoid fossils began appearing within this stage after first appearing in previous stage and began to evolutionarily radiate within this stage, in which a new ammonoid order Goniatitida rises in the end of Zlichovian stage (Siberian representation; corresponds to early Eifelian and after the end of Early Devonian, before 391.9 mya).[2][3] Later agoniatitid ammonoids would die out in the Taghanic event in the upper middle Givetian. Goniatite ammonoids would give rise to further ammonoid orders, thus starting ammonoid dominance of marine fossils in further periods until their end at the Cretaceous-Paleogene mass extinction event.

In North America the Emsian Stage is represented by Sawkill or Sawkillian time.

Palaeontology

Agnathans

Agnathans of the Emsian
Taxa Presence Location Description Images
Lochkovian-Emsian Hunsrück Slate Formation, Germany among others in Europe
Lochkovian-Emsian Wayne Hereford Quarry, England & Podolia, Ukraine
Beartooth Butte Formation, Wyoming & Idaho, USA
Lochkovian-Emsian Britain & Belgium

Placoderms

Placoderms of the Emsian
Taxa Presence Location Description Images
Hunsrück Slate Formation, Germany

References

  1. ↑ http://www.stratigraphy.org/index.php/ics-chart-timescale
  2. ↑ Klug, Christian (July 30, 1999). "Early Emsian ammonoids from the eastern Anti-Atlas (Morocco) and their succession". SpringerLink. Retrieved June 26, 2018.
  3. ↑ Chlupac, I.; Lukes, P. (January 1999). "Pragian/Zlichovian and Zlichovian/Dalejan boundary sections in the Lower Devonian of the Barrandian Area, Czech Republic". ResearchGate. Retrieved June 26, 2018.


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