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 407.6 ± 2.6 million years ago to 393.3 ± 1.2 million years ago. It was preceded by the Pragian stage and followed by the Eifelian stage. It is named after the Ems river in Germany.[2]

DescriptionEdit

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).[3][4] 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.

Emsian lifeEdit

AgnathansEdit

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

PlacodermsEdit

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

ReferencesEdit

  1. ^ http://www.stratigraphy.org/index.php/ics-chart-timescale
  2. ^ "Emsian stage". Encyclopedia Britannica. Retrieved 2 October 2019.
  3. ^ Klug, Christian (July 30, 1999). "Early Emsian ammonoids from the eastern Anti-Atlas (Morocco) and their succession". Paläontologische Zeitschrift. 74 (4): 479–515. doi:10.1007/BF02988158.
  4. ^ 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.