Valanginian

System/
Period		 Series/
Epoch		 Stage/
Age		 Age (Ma)
Paleogene Paleocene Danian younger
Cretaceous Upper/
Late		 Maastrichtian 66.0–72.1
Campanian 72.1–83.6
Santonian 83.6–86.3
Coniacian 86.3–89.8
Turonian 89.8–93.9
Cenomanian 93.9–100.5
Lower/
Early		 Albian 100.5–~113.0
Aptian ~113.0–~125.0
Barremian ~125.0–~129.4
Hauterivian ~129.4–~132.9
Valanginian ~132.9–~139.8
Berriasian ~139.8–~145.0
Jurassic Upper/
Late		 Tithonian older
Subdivision of the Cretaceous system
according to the IUGS, as of July 2012.

In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian stage succeeds the Berriasian stage of the Lower Cretaceous and precedes the Hauterivian stage of the Lower Cretaceous.[1]

Stratigraphic definitions

The Valanginian was first described and named by Édouard Desor in 1853. It is named after Valangin, a small town north of Neuchâtel in the Jura Mountains of Switzerland.

The base of the Valanginian is at the first appearance of calpionellid species Calpionellites darderi in the stratigraphic column. A global reference section (a GSSP) had in 2009 not yet been appointed.

The top of the Valanginian (the base of the Hauterivian) is at the first appearance of the ammonite genus Acanthodiscus.

Subdivision

The Valanginian is often subdivided in Lower and Upper substages. The Upper substage begins at the first appearance of ammonite species Saynoceras verrucosum and the major marine transgression Va3.

In the Tethys domain, the Valanginian stage contains five ammonite biozones:

Palaeontology

†Ankylosaurs

Ankylosauria of the Valanginian
Taxa Presence Location Description Images
Hylaeosaurus

Birds (avian theropods)

Birds of the Valanginian
Taxa Presence Location Description Images
France

Crocodylomorphs

Crocodylomorphs of the Valanginian
Taxa Presence Location Description Images
Dakosaurus
Enaliosuchus

†Ornithopods

Ornithopoda of the Valanginian
Taxa Presence Location Description Images
Australia May be a chimera based on multiple species of ornithopods.
Iguanodon
Lanzhousaurus
Valdosaurus
Europe First dinosaur ever found
Cape Province, South Africa Generally considered nomen dubium, it classified as a genus similar to Dryosaurus, i.e. an iguanodont.
Lanzhou, Gansu, China Notable for its "astonishingly huge teeth", among the largest for any herbivorous creature ever, which indicate it is an iguanodont. The mandible, longer than one meter, suggests very large size for the animal.
Isle of Wight, England; Niger, Africa A dryosaurid

†Pterosaurs

Pterosaurs of the Valanginian
Taxa Presence Location Description Images
Lonchodectes (left)
Pterodaustro
Lagarcito Formation, San Luis Province, Argentina; Chile

†Sauropods

Sauropods of the Valanginian
Taxa Presence Location Description Images

†Stegosaurs

Stegosaurs of the Valanginian
Taxa Presence Location Description Images
Wuerhosaurus

†Theropods (non-avian)

Non-Avian Theropods of the Valanginian
Taxa Presence Location Description Images
Nqwebasaurus

References

Notes

  1. ↑ See Gradstein et al. (2004) for a detailed geologic timescale
  2. 1 2 3 4 5 6 7 8 Dating uncertain.
  3. 1 2 Only known from this stage.

Literature

External links

Cretaceous Period
Lower/Early Cretaceous Upper/Late Cretaceous
Berriasian | Valanginian | Hauterivian
Barremian| Aptian | Albian		 Cenomanian | Turonian | Coniacian
Santonian |Campanian | Maastrichtian
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