Valanginian

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.[2]

Valanginian
~139.8 – ~132.6 Ma
Chronology
Key events in the Cretaceous
-140 —
–
-130 —
–
-120 —
–
-110 —
–
-100 —
–
-90 —
–
-80 —
–
-70 —
–
An approximate timescale of key Cretaceous events.
Axis scale: millions of years ago.
Etymology
Name formalityFormal
Usage information
Celestial bodyEarth
Regional usageGlobal (ICS)
Time scale(s) usedICS Time Scale
Definition
Chronological unitAge
Stratigraphic unitStage
Time span formalityFormal
Lower boundary definitionNot formally defined
Lower boundary definition candidatesFAD of the Calpionellid Calpionellites darderi
Lower boundary GSSP candidate section(s)
Upper boundary definitionFAD of the Ammonite genus Acanthodiscus
Upper boundary GSSPLa Charce, Drôme, France
44.4694°N 5.4437°E / 44.4694; 5.4437
GSSP ratifiedDecember 2019[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:

  • zone of Criosarasinella furcillata
  • zone of Neocomites peregrinus
  • zone of Saynoceras verrucosum
  • zone of Busnardoites campylotoxus
  • zone of Tirnovella pertransiens

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
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
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
Berriasian-Albian UK
Pterodaustro
Lagarcito Formation, San Luis Province, Argentina; Chile
Sussex, England

†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

Berriasian-Barremian

Sao Khua Formation, Thailand
Late Valanginian, 136 Ma Tunbridge Wells Sand Formation, England A possible senior synonym of Thecocoelurus.

References

Notes
  1. Mutterlose, Jörg; Rawson, Peter; Reboulet, Stéphane; Baudin, François; Bulot, Luc; Emmanuel, Laurent; Gardin, Silvia; Martinez, Mathieu; Renard, Maurice (September 2020). "The Global Boundary Stratotype Section and Point (GSSP) for the base of the Hauterivian Stage (Lower Cretaceous), La Charce, southeast France". Episodes. doi:10.18814/epiiugs/2020/020072. Retrieved 24 December 2020.
  2. See Gradstein et al. (2004) for a detailed geologic timescale
  3. Dating uncertain.
  4. Only known from this stage.

Literature
  • Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; (2004): A Geologic Time Scale 2004, Cambridge University Press.
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