Valanginian
Encyclopedia
In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous
Early Cretaceous
The Early Cretaceous or the Lower Cretaceous , is the earlier or lower of the two major divisions of the Cretaceous...

. It spans between 140.2 ± 3.0 Ma and 136.4 ± 2.0 Ma (million years ago). The Valanginian stage succeeds the Berriasian
Berriasian
In the geological timescale, the Berriasian is an age or stage of the Early or Lower Creteceous. It is the oldest or lowest subdivision in the entire Cretaceous. It spanned between 145.5 ± 4.0 Ma and 140.2 ± 3.0 Ma...

 stage of the Lower Cretaceous and precedes the Hauterivian
Hauterivian
The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous epoch or a stage in the Lower Cretaceous series. It spans the time between 136.4 ± 2 Ma and 130 ± 1.5 Ma...

 stage of the Lower Cretaceous.

Stratigraphic definitions

The Valanginian was first described and named by Édouard Desor in 1853. It is named after Valangin
Valangin
Valangin is a municipality in the district of Val-de-Ruz in the canton of Neuchâtel in Switzerland.-Geography:Valangin has an area, , of . Of this area, or 39.4% is used for agricultural purposes, while or 49.7% is forested...

, a small town north of Neuchâtel in the Jura Mountains
Jura mountains
The Jura Mountains are a small mountain range located north of the Alps, separating the Rhine and Rhone rivers and forming part of the watershed of each...

 of Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....

.

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
Ammonite
Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct subclass within the Molluscan class Cephalopoda which are more closely related to living coleoids Ammonite, as a zoological or paleontological term, refers to any member of the Ammonoidea an extinct...

 genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 Acanthodiscus
Acanthodiscus
Acanthodiscus is an extinct ammonoid cephalopod genus from the order Ammonitida and included in the persphinctacean family Berriasellidae. The type, named by Bruguière ,1779, is Acanthodiscus radiatus.-Description:...

.

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
Tethys Ocean
The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia during the Mesozoic era before the opening of the Indian Ocean.-Modern theory:...

, the Valanginian stage contains five ammonite biozone
Biozone
Biostratigraphic units or Biozones are intervals of geological strata that are defined on the basis of their characteristic fossil taxa....

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

†Ankylosaurs

Ankylosauria
Ankylosauria
Ankylosauria is a group of herbivorous dinosaurs of the order Ornithischia. It includes the great majority of dinosaurs with armor in the form of bony osteoderms. Ankylosaurs were bulky quadrupeds, with short, powerful limbs. They are first known to have appeared in the early Jurassic Period of...

 of the Valanginian
Taxa Presence Location Description Images
  • Hylaeosaurus
    Hylaeosaurus
    Hylaeosaurus is the most obscure of the three animals used by Sir Richard Owen to first define the new group Dinosauria, in 1842. The original specimen, recovered by Gideon Mantell from the Tilgate Forest in the south of England in 1832, now resides in the Natural History Museum of London, where...



Birds

Birds of the Valanginian
Taxa Presence Location Description Images
  • Wyleyia
    Wyleyia
    Wyleyia is a prehistoric bird genus with a single species, Wyleyia valdensis, known from the Early Cretaceous of England. Even this is only known from a single damaged right humerus. It has been named to honor J. F. Wyley, who found the specimen in the Weald Clay deposits of Henfield in Sussex...


  • Crocodylomorphs

    Crocodylomorphs of the Valanginian
    Taxa Presence Location Description Images
    • Dakosaurus lapparenti


    • Enaliosuchus
  • Machimosaurus
    Machimosaurus
    Machimosaurus is an extinct genus of teleosaurid crocodyliform from the Late Jurassic and Early Cretaceous . The type species, Machimosaurus hugii, was found in France. Other fossils have been found in Austria, England, Germany, Portugal and Switzerland...


  • †Ornithopods

    Ornithopoda of the Valanginian
    Taxa Presence Location Description Images
    • Fulgurotherium
      Fulgurotherium
      Fulgurotherium is the name given to a genus of dinosaur from the Early Cretaceous . It lived in what is now Australia.The type species, Fulgurotherium australe, was named by Friedrich von Huene in 1932...

    Australia May be a chimera
    Chimera (paleontology)
    In paleontology, a chimera is a fossil which was reconstructed with elements coming from more than a single species of animal. A now classic example of chimera is Protoavis.-List of paleontological chimeras:*Brontosaurus*Lametasaurus...

     based on multiple species of ornithopods.

    • Iguanodon
      Iguanodon
      Iguanodon is a genus of ornithopod dinosaur that lived roughly halfway between the first of the swift bipedal hypsilophodontids and the ornithopods' culmination in the duck-billed dinosaurs...

    Europe, North America
  • Kangnasaurus
    Kangnasaurus
    Kangnasaurus is a genus of iguanodontian ornithopod dinosaur found in supposedly Early Cretaceous rocks of South Africa. It is known from a tooth and possibly some postcranial remains. At times, it has been considered dubious or a valid genus...

  • Cape Province, South Africa Generally considered nomen dubium, it classified as a genus similar to Dryosaurus, i.e. an iguanodont.
  • Lanzhousaurus
    Lanzhousaurus
    Lanzhousaurus is a genus of dinosaur. Lanzhousaurus lived in the Gansu region of what is now China during the Early Cretaceous. A partial skeleton has been recovered...

  • Lanzhou
    Lanzhou
    Lanzhou is the capital and largest city of Gansu Province in Northwest China. A prefecture-level city, it is a key regional transportation hub, allowing areas further west to maintain railroad connections to the eastern half of the country....

    , 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.
  • Valdosaurus
    Valdosaurus
    Valdosaurus is a genus of bipedal herbivorous iguanodont ornithopod dinosaur found on the Isle of Wight and elsewhere in England. It lived during the Early Cretaceous.-Discovery and naming:...

  • Isle of Wight, England; Niger, Africa A dryosaurid

    †Pterosaurs

    Pterosaurs of the Valanginian
    Taxa Presence Location Description Images
    • Lonchodectes
      Lonchodectes
      Lonchodectes was a genus of pterosaur from several formations dating to the Turonian of England, mostly in the area around Kent...


    • Pterodaustro
      Pterodaustro
      Pterodaustro is a genus of Cretaceous pterodactyloid pterosaur from South America, which lived 105 million years ago.-Naming:The genus was named in 1969 by José Bonaparte as an as yet undescribed nomen nudum. The first description followed in 1970, making the name valid, the type species being...

    Lagarcito Formation, San Luis Province, Argentina; Chile

    †Sauropods

    Sauropods
    Sauropoda
    Sauropoda , or the sauropods , are an infraorder of saurischian dinosaurs. They had long necks, long tails, small heads , and thick, pillar-like legs. They are notable for the enormous sizes attained by some species, and the group includes the largest animals to have ever lived on land...

     of the Valanginian
    Taxa Presence Location Description Images
    • Algoasaurus
      Algoasaurus
      Algoasaurus is a genus of sauropod dinosaur from the Tithonian-early Valanginian-age Late Jurassic-Early Cretaceous Upper Kirkwood Formation of Cape Province, South Africa. It was a neosauropod; although it has often been assigned to the Titanosauridae, there is no evidence for this, and recent...

  • Xenoposeidon
    Xenoposeidon
    Xenoposeidon is a genus of sauropod dinosaur from the Early Cretaceous of England, living about 140 million years ago. It is known from a single partial vertebra with unusual features, unlike those of other sauropods...


  • †Stegosaurs

    Stegosaurs of the Valanginian
    Taxa Presence Location Description Images
    • Craterosaurus
      Craterosaurus
      Craterosaurus was a genus of stegosaurid dinosaur. It lived during the Early Cretaceous around 145-136 million years ago. Its fossils were found in England...


    • Paranthodon
      Paranthodon
      Paranthodon was a dinosaur from the early Cretaceous. It lived in what is now South Africa. It is classified as a stegosaur. It has a long and confusing history. The type species, Paranthodon africanus, comes from a partial skull first described as Palaeoscincus africanus in 1912...

  • Wuerhosaurus
    Wuerhosaurus
    Wuerhosaurus is a genus of stegosaurid dinosaur from the Early Cretaceous Period of China. As such, it was one of the last genera of stegosaurians known to have existed, since most others lived in the late Jurassic.-Discovery and species:...


  • †Theropods (non-avian)

    Non-Avian Theropods of the Valanginian
    Taxa Presence Location Description Images
    • "Ginnareemimus
      Ginnareemimus
      Kinnareemimus is a genus of ornithomimosaurian theropod dinosaur from Thailand. It is known only from incomplete remains including vertebrae, partial pubic bones, metatarsals, and an incomplete fibula...

      "
  • Nqwebasaurus
    Nqwebasaurus
    Nqwebasaurus is the name given to a genus of dinosaur from the Tithonian to Valanginian . It was a basal coelurosaur related to Ornitholestes. Its fossils were found in South Africa in the Kirkwood Formation, which is called Nqweba in the native language of the Xhosa...

  • Phaedrolosaurus
    Phaedrolosaurus
    Phaedrolosaurus was a genus of theropod dinosaur, based on a single tooth possibly from the Valanginian-Albian-age Lower Cretaceous Lianmugin Formation of Wuerho, Xinjiang, China. This tooth, IVPP V 4024-1, was described by Dong Zhiming as like those of Deinonychus, albeit thicker, shorter, and...

  • Xinjiangovenator
    Xinjiangovenator
    Xinjiangovenator is a genus of coelurosaurian dinosaur of the Valanginian to Albian stages of the Early Cretaceous period. Its remains were found in the Lianmuqin Formation of Wuerho, Xinjiang, China, and were first described by Dong Zhiming...


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