{{Short description|Geologic formation in China}} {{Infobox rockunit | name = Xiushan Formation | image = | caption = | type = Geological formation | age = {{fossilrange|Llandovery}} | prilithology = | otherlithology = | namedfor = Xiushan County | namedby = | region = Southern China | country = China | coordinates = | unitof = | subunits = | underlies = | overlies = | thickness = | extent = | area = | map = | map_caption = |period=Silurian}}
The '''Xiushan Formation''' is a palaeontological formation located in China. It dates to the Lower Silurian period. Studies of conodonts found in the formation suggests the lower member and main part of the upper member correspond to the ''Pterospathodus eopennatus'' Superbiozone, whereas the top of the upper member likely correlates with the ''Pterospathodus celloni'' Superbiozone.<ref>{{Cite journal |last1=Chen |first1=Zhongyang |last2=Wang |first2=Chengyuan |last3=Fan |first3=Ru |date=2016-02-16 |editor-last=Jin |editor-first=Jisuo |title=Restudy of the Llandovery conodont biostratigraphy in the Xiushan area, Chongqing City, China |url=http://www.nrcresearchpress.com/doi/10.1139/cjes-2015-0189 |journal=Canadian Journal of Earth Sciences |language=en |volume=53 |issue=7 |pages=651–659 |doi=10.1139/cjes-2015-0189 |bibcode=2016CaJES..53..651C |issn=0008-4077|url-access=subscription }}</ref>
==Fossil content== ===Cartilaginous fish=== {| class="wikitable" align="center" |- ! colspan="6" align="center" | Cartilaginous fish reported from the Xiushan Formation |- ! Genus !! Species !! Presence ! Material !! Notes !! Images |- |''Chenolepis'' |''C. asketa'' |Guizhou.<ref name=":0">{{Cite journal |last1=Andreev |first1=Plamen S. |last2=Zhao |first2=Wenjin |last3=Wang |first3=Nian-Zhong |last4=Smith |first4=Moya M. |last5=Li |first5=Qiang |last6=Cui |first6=Xindong |last7=Zhu |first7=Min |last8=Sansom |first8=Ivan J. |date=2020-02-13 |editor-last=Wong |editor-first=William Oki |title=Early Silurian chondrichthyans from the Tarim Basin (Xinjiang, China) |journal=PLOS ONE |language=en |volume=15 |issue=2 |article-number=e0228589 |doi=10.1371/journal.pone.0228589 |issn=1932-6203 |pmc=7018067 |pmid=32053606 |bibcode=2020PLoSO..1528589A |doi-access=free }}</ref> |Scales.<ref name=":0" /> |Also known from the Ymogantau Formation. | |- |}
===Jawless fish=== {| class="wikitable" align="center" |- ! colspan="6" align="center" | Jawless fish reported from the Xiushan Formation |- ! Genus !! Species !! Presence ! Material !! Notes !! Images |- | ''Dayongaspis'' |''D. colubra'' | Maoyanhe Town, Zhangjiajie, Hunan.<ref>{{Cite journal |last1=Zhang |first1=Yumeng |last2=Li |first2=Xutong |last3=Shan |first3=Xianren |last4=Lin |first4=Xianghong |last5=Tan |first5=Kai |last6=Li |first6=Qiang |last7=Zhao |first7=Wenjin |last8=Tang |first8=Lizhou |last9=Zhu |first9=Min |last10=Gai |first10=Zhikun |date=2023-06-19 |title=The first galeaspid fish (stem-gnathostomata) from the Silurian Xiushan formation of Hunan Province, China |url=https://www.tandfonline.com/doi/full/10.1080/08912963.2023.2225083 |journal=Historical Biology |language=en |pages=1–12 |doi=10.1080/08912963.2023.2225083 |s2cid=259469524 |issn=0891-2963|url-access=subscription }}</ref> | | A galeaspid. | |- |}
===Invertebrates=== ====Eurypterids==== {| class="wikitable" align="center" |- ! colspan="6" align="center" | Eurypterids reported from the Xiushan Formation |- ! Genus !! Species !! Presence ! Material !! Notes !! Images |- |''Terropterus'' |''T. xiushanensis'' |Xiushan.<ref name=":1">{{Cite journal |last1=Wang |first1=Han |last2=Dunlop |first2=Jason |last3=Gai |first3=Zhikun |last4=Lei |first4=Xiaojie |last5=Jarzembowski |first5=Edmund A. |last6=Wang |first6=Bo |date=November 2021 |title=First mixopterid eurypterids (Arthropoda: Chelicerata) from the Lower Silurian of South China |url=https://linkinghub.elsevier.com/retrieve/pii/S2095927321005004 |journal=Science Bulletin |language=en |volume=66 |issue=22 |pages=2277–2280 |doi=10.1016/j.scib.2021.07.019|pmid=36654455 |bibcode=2021SciBu..66.2277W |url-access=subscription }}</ref> |Several specimens.<ref name=":1" /> |A mixopterid. |center|150 px |- |}
== See also == * List of fossil sites
==References==<!-- PALAIOS, 2007, v. 22, p. 155–165 --> {{Reflist}} * {{aut|Vickers-Rich, Patricia & Rich, Thomas Hewett}} (1993); ''Wildlife of Gondwana''. Reed. {{ISBN|0-7301-0315-3}}
Category:Geologic formations of China Category:Silurian System of Asia Category:Silurian China Category:Silurian northern paleotropical deposits Category:Silurian paleontological sites Category:Paleontology in China
{{China-geologic-formation-stub}}