Shinisauria
{{Short description|Clade of lizards}}
{{Automatic taxobox
| fossil_range = Early Cretaceous - present, {{fossil range|124.6|0}}
| image = Chin-krokodilschwanzechse-01.jpg
| image_caption = The Chinese crocodile lizard, the only living member of Shinisauria (Shinisaurus).
| taxon = Shinisauria
| authority = Conrad, 2008
| subdivision_ranks = Subgroups
| subdivision =
{{extinct}}Dalinghosaurus
{{extinct}}Merkurosaurus
{{extinct}}Bahndwivici
}}
File:DalinghesaurusLongidigitus-PaleozoologicalMuseumOfChina-May23-08.jpg, the oldest known shinisaurian]]
Shinisauria is a clade or evolutionary grouping of anguimorph lizards that includes the living Chinese crocodile lizard Shinisaurus and several of its closest extinct relatives. Shinisauria was named in 2008 by Jack Lee Conrad as a stem-based taxon to include all anguimorphs more closely related to Shinisaurus than to Anguis fragilis, Heloderma suspectum or Varanus varius.{{Cite journal | last1 = Conrad | first1 = J. L. | doi = 10.1206/310.1 | title = Phylogeny and Systematics of Squamata (Reptilia) Based on Morphology | journal = Bulletin of the American Museum of Natural History | volume = 310 | pages = 1–182| year = 2008 | s2cid = 85271610 | url = http://digitallibrary.amnh.org/bitstream/2246/5915/1//v3/dspace/updateIngest/pdfs/B310.pdf }} Several recent phylogenetic analyses of lizard evolutionary relationships place Shinisauria in a basal position within the clade Platynota, which also includes monitor lizards, helodermatids, and the extinct mosasaurs. Shinisaurians were once thought to be closely related to the genus Xenosaurus, but they are now considered distant relatives within Anguimorpha.{{Cite journal | last1 = Conrad | first1 = J. L. | last2 = Ast | first2 = J. C. | last3 = Montanari | first3 = S. | last4 = Norell | first4 = M. A. | title = A combined evidence phylogenetic analysis of Anguimorpha (Reptilia: Squamata) | doi = 10.1111/j.1096-0031.2010.00330.x | journal = Cladistics | volume = 27 | issue = 3 | pages = 230 | year = 2011 | s2cid = 84301257 | doi-access = free }} The fossil record of shinisaurians extends back to the Early Cretaceous with Dalinghosaurus, which is from the Aptian aged Yixian Formation of China. Two other extinct shinisaurians are currently known: Bahndwivici from the Eocene of Wyoming and Merkurosaurus from the Late Oligocene of Germany and the Early Miocene of the Czech Republic.{{Cite journal | last1 = Klembara | first1 = J. | doi = 10.1111/j.1475-4983.2007.00732.x | title = A New Anguimorph Lizard from the Lower Miocene of North-West Bohemia, Czech Republic | journal = Palaeontology | volume = 51 | pages = 81–94 | year = 2008 | url = https://zenodo.org/record/848102 | doi-access = free }} An indeterminate shinisaurian is known from an isolated tail found in the Eocene aged Messel pit in Germany.{{Cite journal|last=Smith|first=Krister T.|date=2017-05-04|title=First crocodile-tailed lizard (Squamata: Pan-Shinisaurus ) from the Paleogene of Europe|url=https://www.tandfonline.com/doi/full/10.1080/02724634.2017.1313743|journal=Journal of Vertebrate Paleontology|language=en|volume=37|issue=3|pages=e1313743|doi=10.1080/02724634.2017.1313743|s2cid=89730027 |issn=0272-4634|url-access=subscription}}