{{Short description|Extinct genus of reptiles}} {{Speciesbox | fossil_range = Late Permian (Changhsingian), {{fossilrange|252.2}} | image = | image_caption = | display_parents = 3 | genus = Vigilosaurus | parent_authority = Chen & Liu, 2023 | species = gaochangensis | authority = Chen & Liu, 2023 }}
'''''Vigilosaurus''''' is an extinct genus of reptiles from the Permian-aged Guodikeng Formation of Xinjiang, China. The genus contains a single species, '''''Vigilosaurus gaochangensis,''''' known from a partial left hindlimb.<ref name="Chen & Liu 2023">{{Cite journal |last1=Chen |first1=Jianye |last2=Liu |first2=Jun |date=2023 |title=A late Permian archosauriform from Xinjiang shows evidence of parasagittal posture |url=https://doi.org/10.1007/s00114-022-01823-8 |journal=The Science of Nature |language=en |volume=110 |issue=1 |page=1 |doi=10.1007/s00114-022-01823-8 |pmid=36469133 |issn=1432-1904|url-access=subscription }}</ref>
== Classification == When it was described in 2023, the ''Vigilosaurus'' holotype was identified as a possible member of the archosauriform clade Proterochampsia. This would make ''Vigilosaurus'' one of the oldest known archosauromorphs, indicating they had diversified much more rapidly than previously thought.<ref name="Chen & Liu 2023" /> However, a 2025 publication revisited the specimen, recovering it outside of the Archosauromorpha altogether. Instead, it was identified as outside of the reptile crown group (Sauria), diverging after the South African genus ''Youngina''.<ref name="Manistropheus">{{Cite journal |last1=Ezcurra |first1=Martín D. |author1-link=Martín Ezcurra |last2=Sues |first2=Hans-Dieter |author2-link=Hans-Dieter Sues |last3=Fröbisch |first3=Jörg |date=2025-12-31 |title=A new late Permian archosauromorph reptile from Germany enhances our understanding of the early diversity of the clade |journal=Journal of Systematic Palaeontology |language=en |volume=23 |issue=1 |doi=10.1080/14772019.2025.2509639 |issn=1477-2019 |doi-access=free}}</ref> These contrasting results are displayed in the cladograms below:
{{col-begin|width=75%}} {{col-2}}'''Topology 1:''' Results of Chen & Liu (2023)<ref name="Chen & Liu 2023" /> {{clade |{{clade |1=Proterosuchidae |2={{clade |1=''Antarctanax'' |2={{clade |1=''Sarmatosuchus'' |2={{clade |1=''Cuyosuchus'' |2={{clade |1=Erythrosuchidae |2={{clade |1=''Dorosuchus'' |2=''Asperoris'' |3={{clade |1=''Euparkeria'' |2={{clade |1=''Halazhaisuchus'' |2={{clade |1=Avemetatarsalia |label2=Proterochampsia |2={{clade |1={{clade |1=''Polymorphodon'' |2={{clade |1='''''Vigilosaurus''''' |2=''Litorosuchus'' |3=''Vancleavea'' }} }} |4={{clade |1=Other proterochampsians }} }} }} }} }} }} }} }} }} }} }}|label1=Archosauriformes}}
{{col-2}}'''Topology 2:''' Results of Ezcurra, Sues & Fröbisch (2025)<ref name="Manistropheus" /> {{clade |{{clade |1=''Orovenator'' |2={{clade |1=''Claudiosaurus'' |2={{clade |1={{clade |1=''Acerosodontosaurus'' |2=''Hovasaurus'' }} |3={{clade |1=''Youngina'' |2={{clade |1='''''Vigilosaurus''''' |2={{clade |1=Choristodera |label2=Sauria |2={{clade |1=Lepidosauromorpha |2={{clade |1=''Manistropheus'' |2={{clade |1={{clade |1=''Aenigmastropheus'' |2=''Protorosaurus'' }} |3={{clade |1=''Jesairosaurus'' + Tanysauria |2=Crocopoda ⇒ Archosauriformes }} }} }} }} }} }} }} }} }} }} }} {{col-end}}
== References == {{reflist}} {{Proterochampsia|B.}} {{taxonbar|from1=Q124978289}}
Category:Archosauriformes Category:Permian reptiles of Asia Category:Permian China Category:Prehistoric reptile genera Category:Fossil taxa described in 2023
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