Chaoyangsauridae

This family is officially defined in the ''[[PhyloCode]]'' as "the largest clade containing ''[[Chaoyangosaurus youngi]]'', but not ''[[Psittacosaurus mongoliensis]]'' and ''[[Triceratops horridus]]''".<ref name="madziaea21">{{cite journal |last1=Madzia |first1=D. |last2=Arbour |first2=V.M. |last3=Boyd |first3=C.A. |last4=Farke |first4=A.A. |last5=Cruzado-Caballero |first5=P. |last6=Evans |first6=D.C. |title=The phylogenetic nomenclature of ornithischian dinosaurs |journal=PeerJ |date=2021 |volume=9 |pages=e12362 |doi=10.7717/peerj.12362|doi-access=free |pmid=34966571 |pmc=8667728 }}</ref>

This family is officially defined in the ''[[PhyloCode]]'' as "the largest clade containing ''[[Chaoyangosaurus youngi]]'', but not ''[[Psittacosaurus mongoliensis]]'' and ''[[Triceratops horridus]]''".<ref name="madziaea21">{{cite journal |last1=Madzia |first1=D. |last2=Arbour |first2=V.M. |last3=Boyd |first3=C.A. |last4=Farke |first4=A.A. |last5=Cruzado-Caballero |first5=P. |last6=Evans |first6=D.C. |title=The phylogenetic nomenclature of ornithischian dinosaurs |journal=PeerJ |date=2021 |volume=9 |pages=e12362 |doi=10.7717/peerj.12362|doi-access=free |pmid=34966571 |pmc=8667728 }}</ref>

Four dinosaur genera, ''[[Chaoyangsaurus]]'', ''[[Xuanhuaceratops]]'', ''[[Yinlong]]'' and ''[[Hualianceratops]]'', are usually considered to belong to the Chaoyangsauridae.<ref>{{cite journal | last1 = Zhao | first1 = X. | last2 = Cheng | first2 = Z. | last3 = Xu | last4 = Makovicky | first4 = P. J. | year = 2006 | title = A new ceratopsian from the Upper Jurassic Houcheng Formation of Hebei, China | journal = Acta Geologica Sinica | volume = 80 | issue = 4| pages = 467–473 }}</ref><ref>{{cite journal | last1 = Han | first1 = Fenglu | last2 = Forster | first2 = Catherine A. | last3 = Clark | first3 = James M. | last4 = Xu | first4 = Xing | year = 2015 | title = A New Taxon of Basal Ceratopsian from China and the Early Evolution of Ceratopsia | journal = PLOS ONE | volume = 10 | issue = 12| page = e0143369 | doi = 10.1371/journal.pone.0143369 | pmid = 26649770 | pmc = 4674058 | doi-access = free }}</ref><ref>{{Cite journal | doi=10.1080/02724634.2015.1029579|title = Cranial anatomy of ''Yinlong'' downsi(Ornithischia: Ceratopsia) from the Upper Jurassic Shishugou Formation of Xinjiang, China| journal=Journal of Vertebrate Paleontology| volume=36| pages=e1029579|year = 2016|last1 = Han|first1 = Feng-Lu| last2=Forster| first2=Catherine A.| last3=Clark| first3=James M.| last4=Xu| first4=Xing|s2cid = 130791053}}</ref> In 2020, Yu ''et al''. classified ''[[Stenopelix]]'' as a chaoyangsaurid.<ref>{{Cite journal |last=Yu |first=Congyu |last2=Prieto-Marquez |first2=Albert |last3=Chinzorig |first3=Tsogtbaatar |last4=Badamkhatan |first4=Zorigt |last5=Norell |first5=Mark |date=2020-09-10 |title=A neoceratopsian dinosaur from the early Cretaceous of Mongolia and the early evolution of ceratopsia |url=https://ddd.uab.cat/pub/artpub/2020/234388/Combio_a2020m9v3p499.pdf |journal=Communications Biology |volume=3 |issue=1 |doi=10.1038/s42003-020-01222-7 |issn=2399-3642|doi-access=free }}</ref> All five animals are more primitive (or basal) than both ''[[Psittacosaurus]]'' and [[neoceratopsia]]ns.

Four dinosaur genera, ''[[Chaoyangsaurus]]'', ''[[Xuanhuaceratops]]'', ''[[Yinlong]]'' and ''[[Hualianceratops]]'', are usually considered to belong to the Chaoyangsauridae.<ref>{{cite journal | last1 = Zhao | first1 = X. | last2 = Cheng | first2 = Z. | last3 = Xu | last4 = Makovicky | first4 = P. J. | year = 2006 | title = A new ceratopsian from the Upper Jurassic Houcheng Formation of Hebei, China | journal = Acta Geologica Sinica | volume = 80 | issue = 4| pages = 467–473 }}</ref><ref>{{cite journal | last1 = Han | first1 = Fenglu | last2 = Forster | first2 = Catherine A. | last3 = Clark | first3 = James M. | last4 = Xu | first4 = Xing | year = 2015 | title = A New Taxon of Basal Ceratopsian from China and the Early Evolution of Ceratopsia | journal = PLOS ONE | volume = 10 | issue = 12| page = e0143369 | doi = 10.1371/journal.pone.0143369 | pmid = 26649770 | pmc = 4674058 | doi-access = free }}</ref><ref>{{Cite journal | doi=10.1080/02724634.2015.1029579|title = Cranial anatomy of ''Yinlong'' downsi(Ornithischia: Ceratopsia) from the Upper Jurassic Shishugou Formation of Xinjiang, China| journal=Journal of Vertebrate Paleontology| volume=36| pages=e1029579|year = 2016|last1 = Han|first1 = Feng-Lu| last2=Forster| first2=Catherine A.| last3=Clark| first3=James M.| last4=Xu| first4=Xing|s2cid = 130791053}}</ref> In 2020, Yu ''et al''. classified ''[[Stenopelix]]'' as a chaoyangsaurid.<ref>{{Cite journal |last=Yu |first=Congyu |last2=Prieto-Marquez |first2=Albert |last3=Chinzorig |first3=Tsogtbaatar |last4=Badamkhatan |first4=Zorigt |last5=Norell |first5=Mark |date=2020-09-10 |title=A neoceratopsian dinosaur from the early Cretaceous of Mongolia and the early evolution of ceratopsia |url=https://ddd.uab.cat/pub/artpub/2020/234388/Combio_a2020m9v3p499.pdf |journal=Communications Biology |volume=3 |issue=1 |doi=10.1038/s42003-020-01222-7 |issn=2399-3642|doi-access=free }}</ref>

==See also==

==See also==