Givetian

The Givetian is one of two faunal stages in the Middle Devonian period. It lasted from 387.7 million years ago to 382.7 million years ago. It was preceded by the Eifelian stage and followed by the Frasnian stage. It is named after the town of Givet in France. The oldest forests occurred during the late Givetian.[2]

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]

Name and definition

The Givetian stage was proposed in 1879 by French geologist Jules Gosselet and was accepted for the higher stage of the Middle Devonian by the Subcommission on Devonian Stratigraphy in 1981.[3]

Givetian life

Fish

Sarcopterygians
Actinistia
Actinistians of the Frasnian
Taxa Presence Location Description Images
Gavinia Upper Givetian Bindaree Formation, Victoria, Australia A basal actinistian
Tetrapodomorphs
Tetrapodomorphs of the Givetian
Taxa Presence Location Description Images
Elpistostege Escuminac Formation, Quebec, Canada A very basal stegocephalian and a sister taxon of either Tiktaalik or tetrapods.
Livoniana upper Givetian Gauja Formation, Latvia A transitional form between fish and the earliest stegocephalian tetrapodomorphs.
Platycephalichthys upper Givetian A derived eotetrapodiform fish very closely related to Elpistostegalia that includes tetrapods.
Tinirau upper Givetian Red Hill Formation, Eureka County, Nevada A derived eotetrapodiform fish closely related to Elpistostegalia that includes tetrapods.
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References
  1. http://www.stratigraphy.org/index.php/ics-chart-timescale
  2. Becker, R.T.; Gradstein, F.M.; Hammer, O. (2012). "Chapter 22 - The Devonian Period". In Gradstein, F.M.; Ogg, J.G.; Schmitz, M.D.; Ogg, G.M. (eds.). The Geologic Timescale 2012. Elsevier. p. 578. doi:10.1016/b978-0-444-59425-9.00022-6. ISBN 978-0-444-59425-9.
  3. Préat, Alain; Bultynck, Pierre (2006). "Givetian" (PDF). Geologica Belgica. 9 (1–2): 9–18. Retrieved 12 March 2013.

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