Definitions

diachronism

Barremian

The Barremian faunal stage was a period of geological time between 130.0 ± 1.5 mya (million years ago) and 125.0 ± 1.0 mya). It is considered to be of the Early Cretaceous epoch, in which it constituted the earliest part of the obsolete Gallic (according to some classifications the Urgonian) epoch. It is preceded by the Hauterivian and followed by the Aptian stage.

In North America, the late Coahulian and the early Comanchean correspond to the Barremian. In New Zealand, it falls within the Mokoiwian, and in Japan it corresponds to the late Aritan.

The type locality for the Barremian stage is in the vicinity of the village of Barrême, Alpes-de-Haute-Provence, France. Henry Coquand defined the stage and named it in 1873. The base of the Barremian is determined by the first appearance of the ammonites Spitidiscus hugii and Spitidiscus vandeckii. The end of the Barremian is determined by the geomagnetic reversal at the start of the M0r chronozone, which is biologically near the first appearance of the ammonite Paradeshayesites oglanlensis.

Fauna

Much knowledge about the Barremian fauna - especially regarding birds, mammals and pterosaurs - derived from the famous Yixiang Formation of China, part of which dates from this stage.

Cephalopods

Ammonoidea

Neocoleoids

Neocoleoids of the Barremian
Taxa Presence Location Description Images
Maioteuthis
''Neololigosepia
Oxyteuthis

Belemnites

Belemnites of the Barremian
Taxa Presence Location Description Images
Curtohibolites
Neohibolites
Oxyteuthis

Nautiloidea

Nautiloids of the Bajocian
Taxa Presence Location Description Images
Eucymatoceras
Palelialia
Pseudaturoidea

Chondrichthyes

Squamata

Dinosaurs (including birds)

Cerapoda

Marginocephalia

Sauropoda

Theropoda

Thyreophora

Mammals

Mammals of the Barremian
Taxa Presence Location Description Images
Eobaatar several species from Hauterivian to Albian Spain, Mongolia
Eomaia

Pterosaurs

See also

Footnotes

References

  • (1907): Le Barrémien supérieur à faciès Urgonien de Brouzet-lès-Alais (Gard). Mémoires de la Société Géologique de France, Paléontologie 15(37): 5-42.
  • (2006): Assessment of diachronism of biostratigraphic boundaries by magnetochronological calibration of zonal scales for the Lower Cretaceous of the Tethyan and Boreal belts. Doklady Earth Sciences 409(6): 843-846.

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