Anisian

System/
Period
Series/
Epoch
Stage/
Age
Age (Ma)
Jurassic Lower/
Early
Hettangian younger
Triassic Upper/
Late
Rhaetian 201.3 ~208.5
Norian ~208.5 ~227
Carnian ~227 ~237
Middle Ladinian ~237 ~242
Anisian ~242 247.2
Lower/
Early
Olenekian 247.2 251.2
Induan 251.2 251.902
Permian Lopingian Changhsingian older
Subdivision of the Triassic system
according to the ICS, as of 2020.[1]

In the geologic timescale, the Anisian is the lower stage or earliest age of the Middle Triassic series or epoch and lasted from 247.2 million years ago until 242 million years ago.[2] The Anisian age succeeds the Olenekian age (part of the Lower Triassic epoch) and precedes the Ladinian age.

The Muschelkalk in Europe is mainly Anisian aged

Stratigraphic definitionsEdit

The stage and its name were established by Austrian geologists Wilhelm Heinrich Waagen and Carl Diener in 1895. The name comes from Anisus, the Latin name of the river Enns. The original type locality is at Großreifling in the Austrian state of Styria.

The base of the Anisian stage (also the base of the Middle Triassic series) is sometimes laid at the first appearance of conodont species Chiosella timorensis in the stratigraphic record. Other stratigraphers prefer to use the base of magnetic chronozone MT1n. The global reference profile for the base (the GSSP or golden spike) is at a flank of the mountain Deşli Caira in the Romanian Dobruja.[3]

The top of the Anisian (the base of the Ladinian) is at the first appearance of ammonite species Eoprotrachyceras curionii and the ammonite family Trachyceratidae. The conodont species Neogondolella praehungarica appears at the same level.

Especially in Central Europe the Anisian stage is sometimes subdivided into four substages: Aegean, Bythinian, Pelsonian and Illyrian.

The Anisian contains six ammonite biozones:

Anisian lifeEdit

ChondrichthyansEdit

Chondrichthyes of the Anisian
Taxa Presence Location Description Images
Mooreodontus Triassic Australia An xenacanth elasmobranch[4]

ActinopterygiansEdit

Actinopterygii of the Anisian
Taxa Presence Location Description Images
Triassic China, Switzerland, Italy A non-neopterygian
Lopingian to Middle Triassic Switzerland, Italy A non-neopterygian
Early Triassic to Early Jurassic Netherlands, Germany A neopterygian
Early Triassic to Middle Triassic China A non-neopterygian
Middle Triassic to Early Jurassic Switzerland, Italy A non-neopterygian
Triassic China, United States, Switzerland, Italy A non-neopterygian

†TemnospondylsEdit

Temnospondyli of the Anisian
Taxa Presence Location Description Images
Antarctosuchus
  • A polyodon
Upper Fremouw Formation, Antarctica A mastodonsaurid capitosaurian amphibian.
Batrachosuchus
  • B. browni
  • B. concordi
Ntawere Formation, Zambia
Burgersdorp Formation, South Africa
Blina Shale, Australia
A genus of brachyopid trematosaurian amphibians.
Calmasuchus Middle Triassic Areniscas y Lutitas del Figaro Formation, Spain A capitosaurian amphibian.
Cherninia Denwa Formation, India A giant mastodonsaurid capitosaurian amphibian.
Eocyclotosaurus Grès à Voltzia Formation, France
Röt Formation, Germany
Otter Sandstone Formation, UK
Moenkopi Formation, Arizona
A capitosaurian amphibian.
Eryosuchus Yerrapalli Formation, India
Donguz Formation, Russia
A very large mastodonsaurid capitosaurian amphibian that could reach up to 3.5 m in length.
Kryostega Upper Fremouw Formation, Antarctica A large stereospondyl amphibian.
Notobrachyops Ashfield Shale, New South Wales, Australia. A brachyopid trematosaurian amphibian.
Quasicyclotosaurus Aegean-Bithynian Arizona A heylerosaurid capitosaurian amphibian.
Paracyclotosaurus
  • P. davidi
  • P. crookshanki
  • P. morganorum
Middle Triassic
  • P. davidi: Australia
  • P. crookshanki: India.
  • P. morganorum: South Africa
A genus of mastodonsaurid capitosaurian amphibians.
Parotosuchus Fremouw Formation, Antarctica A mastodonsaurid capitosaurian amphibian.
Stanocephalosaurus Middle Triassic Africa; North America A genus of mastodonsaurid capitosaurian amphibians.
Stenotosaurus Middle Triassic Germany, England A capitosaurian amphibian.
Vanastega Cynognathus Assemblage Zone, Burgersdorp, South Africa. A brachyopid trematosaurian amphibian.
Vigilius Aegean/Bithynian Arizona A brachyopid trematosaurian amphibian.
Wellesaurus Middle Triassic USA, South Africa A capitosaurian amphibian.
Xenotosuchus Middle Triassic South Africa A mastodonsaurid capitosaurian amphibian.
Yuanansuchus China A heylerosaurid capitosaurian amphibian.

†IchthyopterygiansEdit

Ichthyopterygia of the Anisian
Taxa Presence Location Description Images
Cymbospondylus Middle Triassic Switzerland, United States An elongate ichthyosaur
Mixosaurus Middle Triassic Switzerland, Italy An ichthyosaur
Omphalosaurus Early to Middle Triassic United States An early ichthyosauriform with button-like teeth
Thalattoarchon Middle Triassic United States One of the first marine macropredators after the Permian-Triassic extinction capable of eating prey that was similar in size to itself

†ThalattosauriansEdit

Thalattosauria of the Anisian
Taxa Presence Location Description Images
Askeptosaurus Middle Triassic Besano Formation, Italy An askeptosauroid thalattosaur
Clarazia Middle Triassic Besano Formation, Switzerland A thalattosauroid thalattosaur
Hescheleria Middle Triassic Besano Formation, Switzerland A thalattosauroid thalattosaur
Thalattosaurus Mid to Late Triassic Canada Thalattosaurus was a thalattosauroid thalattosaur in the family Thalattosauridae.

†HelveticosauridsEdit

Helveticosaurids of the Anisian
Taxa Presence Location Description Images
Helveticosaurus Anisian-Ladinian boundary Switzerland
Eusaurosphargis Anisian-Ladinian boundary Italy
Netherlands

†SaurosphargidsEdit

Saurosphargids of the Anisian
Taxa Presence Location Description Images
Largocephalosaurus Guanling Formation, China
Saurosphargis Poland
Netherlands
Sinosaurosphargis Guanling Formation, China

†SauropterygiansEdit

Sauropterygia of the Anisian
Taxa Presence Location Description Images
Atopodentatus Middle Triassic China A basal sauropterygian. It is the earliest known herbivorous marine reptile.
Diandongosaurus Middle Triassic China A basal eosauropterygian
Wumengosaurus Middle Triassic China A basal eosauropterygian

†PistosaursEdit

Pistosauria of the Anisian
Taxa Presence Location Description Images
Augustasaurus Middle Triassic United States A sauropterygian
Cymatosaurus latest Olenekian to Anisian Germany; Netherlands A sauropterygian
Pistosaurus Anisian–Ladinian France; Germany A sauropterygian

†PachypleurosaursEdit

Pachypleurosauria of the Anisian
Taxa Presence Location Description Images
Anarosaurus Middle Triassic Netherlands A sauropterygian
Dactylosaurus Middle Triassic Central Europe A sauropterygian
Dianopachysaurus Middle Triassic China A sauropterygian
Keichousaurus Middle Triassic China A sauropterygian
Odoiporosaurus Middle Triassic Italy A sauropterygian
Serpianosaurus
  • S. germanicus
upper Pelsonian Germany A sauropterygian

†NothosaursEdit

Nothosaurs of the Anisian
Taxa Presence Location Description Images
Ceresiosaurus Middle Triassic Italy, Switzerland Possibly a synonym of Lariosaurus
Germanosaurus Middle Triassic Germany A sauropterygian
  • Lariosaurus
    • Lariosaurus vosseveldensis
    • Lariosaurus hongguoensis
Middle Triassic China
Netherlands
A sauropterygian
Sanchiaosaurus Middle Triassic China A basal nothosauroid
Silvestrosaurus Anisian-Ladinian boundary Switzerland Possibly a species of Lariosaurus

†PlacodontsEdit

Placodonts of the Anisian
Taxa Presence Location Description Images
Cyamodus A derived cyamodontoid placodont
Palatodonta early Anisian Netherlands A basal placodontiform sauropterygian
Paraplacodus Northern Italy A basal placodont
Pararcus Middle Triassic Netherlands A basal placodont
Placodus Middle Triassic Europe A basal placodont

ArchosauromorphsEdit

†RhynchosaursEdit

Rhynchosauria of the Anisian
Taxa Presence Location Description Images
Moenkopi Formation, Arizona A genus of hyperodapedontid rhynchosaur.
late Anisian Otter Sandstone Formation, England A genus of hyperodapedontid rhynchosaur
early Anisian Burgersdorp Formation, South Africa A basal rhynchosaur
late Anisian Otter Sandstone Formation, England A genus of hyperodapedontid rhynchosaur
early Anisian Burgersdorp Formation, South Africa One of the most basal rhynchosaurs
Bromsgrove Sandstone Formation, Warwickshire, England A rather basal rhynchosaur, possibly a close relative of Rhynchosaurus
Yerrapalli Formation, India A genus of hyperodapedontid rhynchosaur.
early Anisian Burgersdorp Formation, South Africa One of the most basal rhynchosaurs. It was small, measuring at around 30 cm (12 in) of length.
Tarporley Siltstone Formation, England The first rhynchosaur to be described. It had a rather basal position in Rhynchosauria.
late Anisian Tanganyika Territory, Tanzania. A genus of hyperodapedontid rhynchosaur.

†TanystropheidsEdit

Tanystropheids of the Anisian
Taxa Presence Location Description Images
Amotosaurus early Anisian Röt Formation, Black Forest, southwestern Germany
Vossenveld Formation, Netherlands
Dinocephalosaurus Guanling Formation, China A genus of long necked, aquatic archosauromorph. One particular specimen is notable for containing an embryo in its abdominal region strongly indicating viviparous reproduction.
Macrocnemus late Anisian to Ladinian Besano Formation, Italy & Switzerland
Falang Formation, China
Prosanto Formation, Switzerland
Pectodens Guanling Formation, China
Protanystropheus
  • P. antiquus
Poland; Germany; Austria; Netherlands This species was first described under the name Tanystropheus antiquus, some authors still prefer to include this species within Tanystropheus.
Tanystropheus Middle Triassic to Late Triassic Falang Formation, China
Muschelkalk Group, Germany
Besano & Meride Formations, Switzerland
Otter Sandstone Formation, UK
Gevanim Formation, Israel

ArchosauriformsEdit

Archosauriforms of the Anisian
Taxa Presence Location Description Images
Donguz Formation, Russia An archosauriform closely related to archosaurs, similar in biology to euparkeriids.
South Africa Euparkeria is an extinct genus of archosauriform. It was a small reptile that was close to the ancestry of Archosauria.
Ermaying Formation, Shaanxi, China A basal archosauriform, may be a chimera of fossils from the erythrosuchid Shansisuchus and an indeterminate archosaur.
Ermaying Formation, Shaanxi, China A basal archosauriform, a member of Erythrosuchidae.
Ermaying Formation, Shaanxi, China A euparkeriid closely related to Euparkeria.
Ermaying Formation, Shaanxi, China An erythrosuchid.
Donguz Formation, Russia A basal archosauriform, previously thought to be a close relative of Proterosuchus, a more basal taxon.
Donguz Formation, Russia An erythrosuchid archosauriform.
Donguz Formation, Russia A basal non-archosaurian archosauriform, possibly an erythrosuchid.
Ermaying Formation, Shaanxi, China A dubious basal archosauriform. Might be an euparkeriid or even a suchian archosaur.
ArchosaursEdit
Archosaurs of the Anisian
Taxa Presence Location Description Images
Moenkopi Formation, Arizona A ctenosauriscid poposauroid paracrocodylomorph.
Manda Beds, Tanzania A silesaurid dinosauriform.
Bromsgrove Sandstone Formation, England A ctenosauriscid suchian.
Anisian to early Ladinian Donguz Formation, Orenburg Oblast, Russia A member of Aphanosauria, basal relatives of dinosaurs and pterosaurs.
Manda Formation, Tanzania A ctenosauriscid suchian.
Ntawere Formation, Zambia A silesaurid dinosauriform.
Manda Formation, Tanzania A genus of loricatan suchian more basal than Prestosuchus.
Manda Beds, Tanzania Possibly a dinosaur, the earliest known.
Guanling Formation, Pan County, China A genus of aquatic poposauroid archosaur.
Manda Formation, Tanzania A genus of loricatan suchian or possibly a species of Prestosuchus.
Manda Formation, Tanzania An aphanosaurian archosaur.
Grenzbitumenzone, Switzerland and Italy A genus of suchian archosaurs. Ticinosuchus shares many similarities with Paracrocodylomorpha.
Northwestern China A genus of suchian archosaurs, possibly a gracilisuchid. The classification of Turfanosuchus has gone through much revision in the past due to its combination of features from both suchian archosaurs and earlier archosaur relatives such as Euparkeria.
  • "Waldhaus" ctenosauriscid
Röt Formation, Germany A yet unnamed taxon of ctenosauriscid archosaur.
Yerrapalli Formation, India An aphanosaurian archosaur.
All across Europe Zanclodon is the name formally used for fossil material that might actually belongs to at least two genera of dinosaur from the Late Triassic among other genera.

ParareptiliaEdit

Parareptiles of the Anisian
Taxa Presence Location Description Images
Ermaying Formation, China A genus of procolophonid parareptile in the subfamily Leptopleuroninae.
Ermaying Formation, China A genus of procolophonid parareptile in the subfamily Leptopleuroninae.

TherapsidsEdit

Therapsids of the Anisian
Taxa Presence Location Description Images
Karoo Supergroup, South Africa A basal kannemeyeriiform dicynodont.
Cerro Bayo de Portrerillos, Cerro de las Cabras Formation, Argentina, South America A genus of cynodonts in the family Galesauridae
Africa, possibly also Eurasian distribution. A genus of kannemeyeriiform dicynodont in the family Kannemeyeridae.
Ermaying Formation, China A genus of baurioidean therocephalian therapsids.
Russia A kannemeyeriiform dicynodont.
Donguz Formation, European Russia A genus of kannemeyeriiform dicynodont in the family Shansiodontidae.
Ermaying Formation, China A genus of kannemeyeriiform dicynodont.
China; South Africa A genus of kannemeyeriiform dicynodont in the family Shansiodontidae.
Tanzania A genus of kannemeyeriiform dicynodont in the family Shansiodontidae.
Argentina A genus of kannemeyeriiform dicynodont in the family Shansiodontidae.

†CeratitidaEdit

Ananorites Arthaberites Beyrichites Bosnites Buddhaites Bukowskiites Caucasites Danubites Gangadharites Japonites Laboceras Longobarditoides Mesocladiscites Noetlingites Parapinacoceras Parasageceras Phyllocladiscites Proavites Pseudodanubites Psilocladiscites Salterites Tropigymnites Xiphogymnites Pararcestes Sageceras

LowerEdit

Alloptychites Anagymnites Grambergia Groenlandites Gymnites Lenotropites Pearylandites Silberlingites Isculites Stenopopanoceras

MiddleEdit

Acrochordiceras Alanites Anagymnotoceras Arctohungarites Balatonites Bulogites Cuccoceras Czekanowskites Epacrochordiceras Hollandites Huishuites Inaigymnites Ismidites Kiparisovia Malletophychites Nicomedites Phillipites Platycuccoceras Pronoetlingites Reiflingites Discoptychites Intornites Nevadisculites Paraceratites Parapopanoceras Proarcestes Longobardites Ptychites

UpperEdit

Amphipopanoceras Aplococeras Arctogymnites Eudiscoceras Eutomoceras Gymnotoceras Halilucites Judicarites Kellnerites Metadinarites Nevadites Parakellnerites Proteusites Repossia Semiornites Serpianites Stoppaniceras Ticinites Tozerites Tropigastrites Joannites Epigymnites Ceratites Flexoptychites Frechites Norites Gevanites Hungarites

†PhylloceratidaEdit

Spinoleiophyllites Ussurites Monophyllites

NautilidaEdit

Trachynautilus Thuringionautilus Styrionautilus

LowerEdit

Indonautilus Sibyllonautilus

MiddleEdit

Paranautilus

UpperEdit

Holconautilus Proclydonautilus

†AulacoceridaEdit

Crassiatractites Breviatractites

LowerEdit

Mojsisovicsteuthis

PterioidaEdit

Ramonalinidae

ReferencesEdit

NotesEdit

  1. ^ "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy. 2020.
  2. ^ According to Gradstein et al. (2004); Brack et al. (2005) give 248 to 241 Ma
  3. ^ The GSSP was established by Grǎdinaru et al. (2007)
  4. ^ Ginter, M., Hampe, O., Duffin, C., 2010.Handbook of Paleoichthyology Volume 3D: Chondrichthyes: Paleozoic Elasmobranchii: Teeth. in Schultze, H. (ed.) Handbook of Paleoichthyology. Verlag Dr. Friedrich Pfeil, München

LiteratureEdit

  • Brack, P.; Rieber, H.; Nicora, A. & Mundil, R.; 2005: The Global boundary Stratotype Section and Point (GSSP) of the Ladinian Stage (Middle Triassic) at Bagolino (Southern Alps, Northern Italy) and its implications for the Triassic time scale, Episodes 28(4), pp. 233–244.
  • Grǎdinaru, E.; Orchard, M.J.; Nicora, A.; Gallet, Y.; Besse, J.; Krystyn, L.; Sobolev, E.S.; Atudorei, N.-V. & Ivanova, D.; 2007: The Global Boundary Stratotype Section and Point (GSSP) for the base of the Anisian Stage: Deşli Caira Hill, North Dobrogea, Romania, Albertiana 36, pp. 54–71.
  • Gradstein, F.M.; Ogg, J.G. & Smith, A.G.; 2004: A Geologic Time Scale 2004, Cambridge University Press.

External linksEdit

Coordinates: 45°04′27″N 28°48′08″E / 45.0742°N 28.8022°E / 45.0742; 28.8022