Artinskian

In the geologic timescale, the Artinskian is an age or stage of the Permian. It is a subdivision of the Cisuralian epoch or series. The Artinskian likely lasted between 290.1 and 283.5 million years ago (Ma) according to the most recent revision of the International Commission on Stratigraphy (ICS) in 2013,[2] though older versions of the ICS preferred a younger age range. It was preceded by the Sakmarian and followed by the Kungurian.

System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Triassic Lower/
Early
Induan younger
Permian Lopingian Changhsingian 251.902 254.14
Wuchiapingian 254.14 259.1
Guadalupian Capitanian 259.1 265.1
Wordian 265.1 268.8
Roadian 268.8 272.95
Cisuralian Kungurian 272.95 283.5
Artinskian 283.5 290.1
Sakmarian 290.1 295.0
Asselian 295.0 298.9
Carboniferous Pennsylvanian Gzhelian older
Subdivision of the Permian system
according to the ICS, as of 2017.[1]

Stratigraphy

Jimbacrinus bostocki Artinskian of Australia. (Found near Jimba Jimba Station )

The Artinskian is named after the small Russian city of Arti (formerly Artinsk), situated in the southern Ural mountains, about 200 km southwest of Yekaterinburg. The stage was introduced into scientific literature by Alexander Karpinsky in 1874.[3]

Base of the Artinskian

The base of the Artinskian stage is defined as the first appearance datum (FAD) of the conodont species Sweetognathus whitei and Mesogondolella bisselli. In order to constrain this age, the ICS subcommission on Permian stratigraphy informally proposed a candidate GSSP in 2002, later followed by a formal proposal in 2013. This candidate GSSP is the Dal'ny Tulkas roadcut in the Southern Urals, near the town of Krasnousolsky.[2]

U-Pb radiometric dating found that the base of the Artinskian was approximately 290.1 million years old (Ma), based on the position of the rock layer at the Dal'ny Tulkas roadcut containing the FAD of S. whitei relative to three precisely dated ash beds surrounding it.[4] Earlier radiometric reported a much younger age of 280.3 Ma for the Sakmarian-Artinskian boundary.

Top of the Artinskian

The top of the Artinskian (and the base of the Kungurian) is defined as the place in the stratigraphic record where fossils of conodonts Neostreptognathodus pnevi and Neostreptognathodus exculptus first appear.[3]

Artinskian life

Arthropods

Arthropoda of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Wellington Formation, Kansas and Oklahoma, United States A dragonfly with a wingspan over 70 cm (28 in)

Cartilaginous fishes

Chondrichthyes of the Artinskian
TaxaPresenceLocationDescriptionImages
Carboniferous to Cisuralian Germany An acanthodian
Carboniferous to Cisuralian Russia A eugeneodontid holocephalian
Cisuralian Russia, Australia An eugeneodont holocephalian, "buzzsaw shark"
  • Triodus
Carboniferous to Cisuralian Germany A xenacanthidan elasmobranch
  • Xenacanthus
Carboniferous to Cisuralian Germany A xenacanthidan elasmobranch

Ray-finned fishes

Actinopterygii of the Artinskian
TaxaPresenceLocationDescriptionImages
Carboniferous to Cisuralian Czech Republic An aeduellid non-neopterygian
Cisuralian Czech Republic, France An amblypterid non-neopterygian

Lungfishes

Dipnoi of the Artinskian
TaxaPresenceLocationDescriptionImages
Carboniferous to Early Triassic North America
Carboniferous to Cisuralian Germany

†Temnospondyls

Temnospondyli of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Texas, United States A temnospondyl
Cisuralian Texas A temnospondyl of uncertain affinities.
Cisuralian Abo Formation, New Mexico and Seymour, Baylor County, Texas
Texas, New Mexico, Oklahoma, United States A zatracheidid.

†Embolomerians

Embolomeri of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Texas, USA A reptiliomorph

†Seymouriamorphs

Seymouriamorpha of the Artinskian
TaxaPresenceLocationDescriptionImages
Boskovice Furrow, Czech Republic A reptiliomorph
  • Seymouria
    • Seymouria baylorensis
    • Seymouria sanjuanensis
USA
Tambach Formation, Germany
A reptiliomorph

†Diadectomorphs

Diadectomorpha of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian North America A reptiliomorph
Cisuralian Germany A reptiliomorph

†Mesosaurs

Mesosauria of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Irati Formation, Paraná Basin, Brazil earliest aquatic reptile
Cisuralian Brazil
Mangrullo Formation, Uruguay
Namibia
South Africa
earliest aquatic reptile
Cisuralian Brazil
South Africa
earliest aquatic reptile

†Procolophonomorphs

Procolophonomorpha of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Europe A genus of lizard-shaped parareptile
Cisuralian North America and North Asia A genus of lizard-shaped parareptile
Cisuralian Oklahoma, United States A lanthanosuchoid parareptile
Cisuralian Germany A genus of biped lizard-shaped parareptile

Eureptilians

Eureptilia of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian North America and Europe A captorhinid reptile
Cisuralian United States A captorhinid reptile

Diapsids

Diapsida of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian North America One of the earliest diapsids

Synapsids

Synapsida of the Artinskian
TaxaPresenceLocationDescriptionImages
Cisuralian Wichita Group, Texas, United States A sphenacodontid
Sakmarian-Kungurian Greene Formation, Ohio; Belle Plains Formation, Texas; Cutler Formation, Utah, all in the USA A sphenacodontid
Cisuralian United States, Canada A sphenacodontid
Pennsylvanian to Cisuralian United States, Germany An edaphosaurid. One of the oldest herbivorous amniotes
Cisuralian United States A caseasaurian
Cisuralian United States A caseasaurian
Kasimovian-Kungurian Kenilworth, Kenilworth Sandstone Formation, Warwickshire Group, Warwickshire, England; Autun, France, Cutler Formation, Arizona, Colorado, New Mexico and Utah; Fort riley, Chase Group, Kansas, Greene Formation, Dunkard Group, Ohio; Wellington Formation, Oklahoma; Clyde Formation, Texas and Oklahoma; Admiral Formation; Belle-Plains Formation; Wichita Group, all three in Texas,
Cisuralian United States A caseasaurian
Wichita Group and Clear Fork Group, both in Texas, USA
Gzhelian-Artinskian New Mexico; Utah-Arizona border region, both in USA; possibly England The English specimen known as S?. brittanicus) is now generally classified as Sphenacodontidae incertae sedis, separate from the other Sphenacodon species so may need reassigning.

References

  1. "Chart/Time Scale". www.stratigraphy.org. International Commission on Stratigraphy.
  2. Chuvashov, Boris I.; Chernykh, Valery V.; Shen, Shuzhong; Henderson, Charles M. (2013). "Proposal for the Global Stratotype Section and Point (GSSP) for the base-Artinskian Stage (Lower Permian)". Permophiles. 58: 26–34.
  3. Gradstein, Felix M.; Ogg, James G.; Smith, Alan G. (2004). A Geologic Time Scale 2004. ISBN 9780521786737.
  4. Schmitz, Mark D.; Davydov, Vladimir I. (March–April 2012). "Quantitative radiometric and biostratigraphic calibration of the Pennsylvanian–Early Permian (Cisuralian) time scale and pan-Euramerican chronostratigraphic correlation". Geological Society of America Bulletin. 124 (3/4): 549–577. doi:10.1130/B30385.1.
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