{{Short description|Sedimentary deposit in China}} {{Use dmy dates|date=April 2022}} {{Infobox rockunit | name = Anji Biota | image = Anji Biota.jpg | caption = Reconstruction of the Anji biota, with several glass sponge species and ''Archopterus''. | type = Lagerstätte | age = {{fossilrange|Hirnantian}} | period = Hirnantian | prilithology =Mudstone | otherlithology = | namedfor = | namedby = | region = Zhejiang Province | country = China | coordinates = | unitof = Wenchang Formation | subunits = | underlies = Anji Formation | overlies = Changwu Formation | thickness = | extent = | area = | map = | map_caption = }}
The '''Anji biota''' is a lagerstätte from the latest Ordovician of China, contained within the '''Wenchang Formation'''. This lagerstätte preserves a mid-diversity fauna mostly consisting of glass sponges.<ref>{{cite journal |last1=Wu |first1=Xuejin |last2=Botting |first2=Joseph P. |last3=Zhang |first3=Yuandong |last4=Muir |first4=Lucy A. |last5=Ma |first5=Junye Y. |title=Taphonomy of exceptional sponge preservation in the Hirnantian Anji Biota, China |journal=Journal of the Geological Society |date=5 September 2022 |volume=179 |issue=5 |doi=10.1144/jgs2021-112}}</ref>
== Paleobiota == {{Paleobiota-key-compact}} {| class="wikitable sortable mw-collapsible" ! colspan="6" align="center" |Paleobiota |- !Genus !Species !Higher taxon !Notes !Images |- |''Archopterus'' |''A. anjiensis'' |Adelophthalmidae |Earliest adelophthalmid, alongside the earliest Chinese eurypterid<ref>{{cite journal |last1=Wang |first1=Han |last2=Braddy |first2=Simon J. |last3=Botting |first3=Joseph |last4=Zhang |first4=Yuandong |title=The first documentation of an Ordovician eurypterid (Chelicerata) from China |journal=Journal of Paleontology |date=May 2023 |volume=97 |issue=3 |pages=606–611 |doi=10.1017/jpa.2023.21}}</ref> |thumb|Reconstruction of ''Archopterus'' in the Anji biota |- |''Anjigraptus'' |''A. wangi'' |Neodiplograptidae? |Independently evolved a morphology similar to dicranograptids<ref>{{cite journal |last1=Muir |first1=Lucy A. |last2=Zhang |first2=Yuandong |last3=Botting |first3=Joseph P. |last4=Ma |first4=Xuan |title=Convergent evolution in planktic graptolites: independent origin of the dicranograptid morphology in the Hirnantian (latest Ordovician) |journal=Alcheringa: An Australasian Journal of Palaeontology |date=2 October 2021 |volume=45 |issue=4 |pages=395–400 |doi=10.1080/03115518.2021.2003430}}</ref> | |- |''Avitograptus'' |''A. avitus'', ''A. akidomorphus'', ''A. acanthocystus'' |Akidograptidae (Graptolithina) |Transitional between earlier and later akidograptids<ref name="graptolite">{{cite journal |last1=Muir |first1=Lucy A. |last2=Zhang |first2=Yuandong |last3=Botting |first3=Joseph P. |last4=Ma |first4=Xuan |title=Avitograptus species (Graptolithina) from the Hirnantian (uppermost Ordovician) Anji Biota of South China and the evolution of Akidograptus and Parakidograptus |journal=Journal of Paleontology |date=September 2020 |volume=94 |issue=5 |pages=955–965 |doi=10.1017/jpa.2020.12}}</ref> | |- |''Anjiplectella'' |''A. davidipharus'' |Euplectellidae |Extends the range of Venus’ flower basket sponges back by almost 150 million years<ref>{{cite journal |last1=Botting |first1=Joseph P. |last2=Janussen |first2=Dorte |last3=Muir |first3=Lucy A. |last4=Dohrmann |first4=Martin |last5=Ma |first5=Junye |last6=Zhang |first6=Yuandong |title=Extraordinarily early Venus' flower basket sponges (Hexactinellida, Euplectellidae) from the uppermost Ordovician Anji Biota, China |journal=Palaeontology |date=March 2022 |volume=65 |issue=2 |doi=10.1111/pala.12592}}</ref> | |- |''Archaeaphorme'' |''A. conica'' |Rossellidae |Resembles the modern ''Aphorme'', but differs in body shape and spicule characteristics<ref name=rossel/> | |- |''Cannapirania'' |''C. vermiformis'' |Piraniidae (Protomonaxonida) |Formerly placed within ''Pirania'' itself<ref>{{cite journal |last1=Botting |first1=Joseph |last2=Stewart |first2=Sarah |last3=Muir |first3=Lucy |last4=Zhang |first4=Yuandong |title=Taxonomy and evolution of the protomonaxonid sponge family Piraniidae |journal=Palaeontologia Electronica |date=2019 |doi=10.26879/998|doi-access=free }}</ref> | |- |''Conciliospongia'' |''C. anjiensis'' |Silicea |Transitional between hexactinellids and demosponges<ref>{{cite journal |last1=Botting |first1=Joseph P. |last2=Zhang |first2=Yuandong |last3=Muir |first3=Lucy A. |title=Discovery of missing link between demosponges and hexactinellids confirms palaeontological model of sponge evolution |journal=Scientific Reports |date=13 July 2017 |volume=7 |issue=1 |doi=10.1038/s41598-017-05604-6|pmc=5509731 }}</ref> | |- |''Crateromorpha''? |''C?. (Neopsacas?) macrospicula'' |Rossellidae |Likely a member of an extant genus<ref name="rossel">{{cite journal |last1=Botting |first1=Joseph P. |last2=Janussen |first2=Dorte |last3=Dohrmann |first3=Martin |last4=Muir |first4=Lucy A. |last5=Zhang |first5=Yuandong |last6=Ma |first6=Junye |title=Advanced crown‐group Rossellidae (Porifera: Hexactinellida) resembling extant taxa from the Hirnantian (Late Ordovician) Anji Biota |journal=Papers in Palaeontology |date=January 2025 |volume=11 |issue=1 |doi=10.1002/spp2.70000}}</ref> | |- |''Eorosselloides'' |''E. antiquus'' |Rossellidae |Very closely resembles the modern ''Rossella'', but too poorly preserved to determine whether it actually belongs to the genus<ref name=rossel/> |- |''Matteolaspongia'' |''M. hemiglobosa'' |Rossellidae? |Either convergently rossellid-like, or in the stem-group of the family<ref>{{cite journal |last1=Botting |first1=J.P. |last2=Zhang |first2=Y. |last3=Muir |first3=L.A. |title=A candidate stem-group rossellid (Porifera, Hexactinellida) from the latest Ordovician Anji Biota, China |journal=Bulletin of Geosciences |date=20 August 2018 |pages=275–285 |doi=10.3140/bull.geosci.1706|doi-access=free }}</ref> | |- |''Pseudanoxycalyx'' |''P. verrucosus'' |Rossellidae |Convergently resembles the modern ''Anoxycalyx''<ref name=rossel/> | |- |''Shouzhispongia'' |''S. coronata'', ''S. prodigia'' |Rossellidae |One of the most common Anji sponges<ref>{{cite journal |last1=Botting |first1=Joseph P. |last2=Janussen |first2=Dorte |last3=Zhang |first3=Yuandong |last4=Muir |first4=Lucy A. |title=Exceptional preservation of two new early rossellid sponges: the dominant species in the Hirnantian (Late Ordovician) Anji Biota of China |journal=Journal of the Geological Society |date=September 2020 |volume=177 |issue=5 |pages=1025–1038 |doi=10.1144/jgs2020-002}}</ref> | |- |}
==References== {{Reflist}}
Category:Geologic formations of China Category:Ordovician System of Asia Category:Ordovician China Category:Hirnantian
{{China-geologic-formation-stub}} {{Ordovician-stub}} {{China-stub}} Category:Lagerstätten