Anisian

From Wikipedia, the free encyclopedia

In the geologic timescale, the Anisian is the lower age of the Middle Triassic epoch and lasted from 245 million years ago until 237 million years ago, approximately. The Anisian age succeeds the Olenekian age of the Lower Triassic epoch and precedes the Ladinian age of the Middle Triassic epoch.

The earliest potential dinosaur fossil to date is a partial pubis from Anisian-age rocks of the Moenkopi Formation, Arizona. It may have come from a herrerasaurid.^[1]

Contents 1 Vertebrate Fauna 1.1 Archosauromorphs (non-archosaurians) 1.2 Therapsids (non-mammalian) 1.3 Nothosauroids 1.4 Placodonts 1.5 Thalattosaurians 2 Invertebrate Fauna 2.1 Ceratitida 2.1.1 Lower 2.1.2 Middle 2.1.3 Upper 2.2 Phylloceratida 2.3 Nautilida 2.3.1 Lower 2.3.2 Middle 2.3.3 Upper 2.4 Aulacocerida 2.4.1 Lower 3 References

[edit] Vertebrate Fauna

• Ichthyosaurs
• Prestosuchids
• Trigoniids

[edit] Archosauromorphs (non-archosaurians)

†Non-archosaurian Archosauromorphs of the Anisian
Taxa	Presence	Location	Description	Images
Erythrosuchus				Erythrosuchus

[edit] Therapsids (non-mammalian)

†Non-mammalian Therapsids of the Anisian
Taxa	Presence	Location	Description	Images
Kannemeyeria				Kannemeyeria.

[edit] Nothosauroids

Nothosauroids of the Anisian
Taxa	Presence	Location	Description	Images
Anarosaurus				Ceresiosaurus Keichousaurus
Ceresiosaurus
Dactylosaurus
Keichousaurus		Guizhou and Hubei, China

[edit] Placodonts

Placodonts of the Anisian
Taxa	Presence	Location	Description	Images
Cyamodus				Cyamodus Paraplacodus
Paraplacodus		Northern Italy

[edit] Thalattosaurians

Thalattosauria of the Anisian
Taxa	Presence	Location	Description	Images
Askeptosaurus		Italy	A very thin, elongated creature (about 2 meters long) that probably swam like an eel, that was probably a fish eater and hunted in deep waters, based on its large eyes (which would allow it to see better in dark water) and the protective bony ring around them (also seen in ichthyosaurs), which prevented them from getting squashed in by the immense water pressure at great depths.	Askeptosaurus

[edit] Invertebrate Fauna

This article may need to be wikified to meet Wikipedia's quality standards. Please help by adding relevant internal links, or by improving the article's layout. (October 2008)

[edit] Ceratitida

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

[edit] Lower

Alloptychites Anagymnites Grambergia Groenlandites Gymnites Lenotropites Pearylandites Silberlingites Isculites Stenopopanoceras

[edit] Middle

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

[edit] Upper

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

[edit] Phylloceratida

Spinoleiophyllites Ussurites Monophyllites

[edit] Nautilida

Trachynautilus Thuringionautilus Styrionautilus

[edit] Lower

Indonautilus Sibyllonautilus

[edit] Middle

Paranautilus

[edit] Upper

Holconautilus Proclydonautilus

[edit] Aulacocerida

Crassiatractites Breviatractites

[edit] Lower

Mojsisovicsteuthis

[edit] References

Triassic period
Lower/Early Triassic	Middle Triassic	Upper/Late Triassic
Induan | Olenekian	Anisian | Ladinian	Carnian | Norian Rhaetian