In the geologic timescale, the Wuchiapingian or Wujiapingian (from Chinese: 吴家坪; pinyin: Wújiāpíng; lit. 'Wu Family Flatland"' in the Liangshan area of Hanzhong, Shaanxi Province^[4]) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian Epoch or Series. The Wuchiapingian spans the time between 259.51 and 254.14 million years ago (Ma). It was preceded by the Capitanian and followed by the Changhsingian.^[5]

Quick Facts Chronology, Etymology ...

Wuchiapingian
259.51 ± 0.21 – 254.14 ± 0.07 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Wuchiapingian aged stratigraphic succession including the Kupferschiefer, Kamsdorf mine near Saalfeld, Thuringia, Germany
Chronology
−300 — – −295 — – −290 — – −285 — – −280 — – −275 — – −270 — – −265 — – −260 — – −255 — – −250 — Paleozoic Mz C Permian Tr P Cisuralian Guadalup Lopin ET Gzhelian Asselian Sakmarian Artinskian Kungurian Roadian Wordian Capitanian Wuchiapingian Changhsingian Induan       ← Permian-Triassic mass extinction event ← end-Capitanian extinction event ← Olson's Extinction Subdivision of the Permian according to the ICS, as of 2022.[1] Vertical axis scale: millions of years ago.
Etymology
Name formality	Formal
Usage information
Celestial body	Earth
Regional usage	Global (ICS)
Time scale(s) used	ICS Time Scale
Definition
Chronological unit	Age
Stratigraphic unit	Stage
Time span formality	Formal
Lower boundary definition	FAD of the Conodont Clarkina postbitteri postbitteri
Lower boundary GSSP	Penglaitan Section, Laibin, Guangxi, China 23.6953°N 109.3211°E / 23.6953; 109.3211
Lower GSSP ratified	2004[2]
Upper boundary definition	Meishan, Zhejiang, China
Upper boundary GSSP	FAD of the Conodont Clarkina wangi 31.0819°N 119.7064°E / 31.0819; 119.7064
Upper GSSP ratified	2005[3]

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Regional stages with which the Wuchiapingian is coeval or overlaps include the Djulfian or Dzhulfian, Longtanian, Rustlerian, Saladoan, and Castilian.^[6]

The Wuchiapingian was first used in 1962, when the Lopingian Series of southwestern China was divided in the Changhsingian and Wuchiapingian Formations. In 1973 the Wuchiapingian was first used as a chronostratigraphic unit (i.e. a stage, as opposed to a formation, which is a lithostratigraphic unit).^[7]

The base of the Wuchiapingian Stage is defined as the place in the stratigraphic record where the conodont species Clarkina postbitteri postbitteri first appears. A global reference profile for this boundary (a GSSP) is located near Laibin in the Chinese province of Guangxi.^[2]

The top of the Wuchiapingian (the base of the Changhsingian) is at the first appearance of conodont species Clarkina wangi.

The Wuchiapingian contains two ammonoid biozones: that of the genus Araxoceras and that of the genera Roadoceras and Doulingoceras.

An extinction pulse occurred during the Wuchiapingian; faunas were recovering when another larger extinction pulse, the Permian–Triassic extinction event devastated life.^[8]

A relatively diverse fish fauna is known from the coeval Kupferschiefer (Werra Formation, Germany), Marl Slate Formation (England) and Ravnefjeld Formation (Greenland), including, among others, the following genera: Acentrophorus, Acropholis, Boreolepis, Coelacanthus, Dorypterus, Janassa, Menaspis, Palaeoniscum, Platysomus, Pygopterus and Wodnika.^[9][10] The Hambast Formation of Iran yielded chondrichthyan faunas of Wuchiapingian to Changhsingian age. The Wuchiapingian layers produced teeth of the eugeneodontid Bobbodus.^[11]

• Cistecephalus Assemblage Zone* (South Africa)
• Hambast Formation (Iran)
• Marl Slate Formation (England)
• Naobaogou Formation (Inner Mongolia, China)
• Ravnefjeld Formation (Greenland)
• Sunjiagou Formation (Shanxi, China)
• Tropidostoma Assemblage Zone* (South Africa)
• Usili Formation* (Tanzania)
• Werra Formation (Kupferschiefer, Germany)

* Tentatively assigned to the Wuchiapingian; age estimated primarily via terrestrial tetrapod biostratigraphy