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]
Palaeontology
Fish
Sarcopterygians
Actinistia
| Actinistians of the Frasnian | ||||
|---|---|---|---|---|
| Taxa | Presence | Location | Description | Images |
| Upper Givetian | Victoria, Australia | A basal actinistian. | ||
Tetrapodomorphs
| Tetrapodomorphs of the Givetian | ||||
|---|---|---|---|---|
| Taxa | Presence | Location | Description | Images |
| Escuminac Formation, Quebec, Canada | A very basal stegocephalian and a sister taxon of either Tiktaalik or tetrapods. | |||
| upper Givetian | Latvia | A transitional form between fish and the earliest stegocephalian tetrapodomorphs. | ||
| upper Givetian | A derived eotetrapodiform fish very closely related to Elpistostegalia that includes tetrapods. | |||
| upper Givetian | Eureka County, Nevada | A derived eotetrapodiform fish closely related to Elpistostegalia that includes tetrapods. | ||
References
- http://www.stratigraphy.org/index.php/ics-chart-timescale
- 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.
- Préat, Alain; Bultynck, Pierre (2006). "Givetian" (PDF). Geologica Belgica. 9 (1–2): 9–18. Retrieved 12 March 2013.
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